Methods and apparatus based on orthogonal hadamard sequences having selected correlation properties

 

The invention relates to telecommunications, and more specifically to synchronization of the transceivers of different users, to synchronize, based on the orthogonal sequences with optimized correlation properties. Technical result - increase system throughput. Methods and apparatus for synchronization of the transmitter and receiver based on orthogonal sequences with optimized correlation properties. The transmitter can generate a version of the S-Hadamard sequences with the sign, which are obtained by scrambling the positions of the set of all sequences of the Walsh-Hadamard transform with a special sequence having complex elements of constant size. The receiver evaluates a temporary position and identification data sequence adopted version of the synchronization signal. 9 N. and 35 C.p. f-crystals, 10 ill., 3 table.

The level of technology

The present invention generally relates to telecommunications and more specifically to synchronization of the transceivers of different users, and more particularly to a method and device for synchronization based on orthosi, such as cellular and satellite communication systems use different modes of operation (analog, digital, and hybrid) and various access technologies, such as multiple access frequency division multiple access (FDMA equipment), multiple access with time division multiplexing (mdvr), multiple access, code-division multiplexing (mdcr), as well as hybrids of these technologies.

Digital cellular communication systems has expanded the functionality to optimize system throughput and maintain hierarchical structures of cells, for example structures macrotec, microwells, pechacek and so on, the Term "macrocell" generally refers to a cell having a size comparable to the cell size in a conventional cellular telephone system (for example, the radius of at least approximately 1 km), and the terms "microcache" and "michoacana", generally speaking, are much smaller cells. For example, microcache could cover buildings or open space public access, such as a conference room or a busy street, and michoacana could cover an office or floor of a tall building. From the point of view of radiokate, to ensure operation in a variety of configurations or can be mutually overlap.

Fig.1 illustrates an example of hierarchical or multi-level cell system. Umbrella macrocell 10 provided in the hexagonal form, overlapping forms a honeycomb structure. Each umbrella cell can contain a composite structure from the microwells. The umbrella cell 10 includes microcase 20, represented by the area encircled by a dotted line, and microcase 30, represented by the area encircled by a dotted line, which correspond to the areas along city streets, and pichacani 40, 50 and 60, which cover separate floors of the building. The intersection of two city streets blocked by a micro-cells 20 and 30, can create a region of high concentration of traffic and thus may represent a "hot spot".

Fig.2 depicts a block diagram of a sample cellular mobile radiotelephone system that includes a base station (BS) 110 and a mobile station (MS) 120. The base station includes a module 130 for control and processing, which is connected with the switching centre mobile (CCMS) 140, which in turn connects to the public switched telephone network (PSTN) (not shown). The basic principles of such a cellular radiotelephone systems etchika 150 voice channels, which is controlled by module 130 management and processing. Also, each base station includes a transceiver 160 of the control channels, which can work with more than one control channel. The transceiver 160 of the control channels is controlled by module 130 management and processing. The transceiver 160 of the control channels transmits the management information on the control channel of the base station or cell to the mobile stations that are synchronized with the control channel. The transceivers 150 and 160 of the control channels can be implemented as a single device, similar to the transceiver 170 voice channel and a control for use with the control channels and traffic that share the same RF carrier.

Mobile station 120 receives information via the control channel, using its transceiver 170 of the speech channel and the control channel. Then the module 180 processing evaluates the received information of the control channels, which includes characteristics of the cells, which can synchronize the mobile station, and determines whether the cell should be synchronized mobile station. Preferably the received information channel which also contains relative information, concerning other cells next to the cell associated with the control channel, as described, for example, in U.S. patent No. 5 353 332 in the name of Raith et al. "Method and apparatus for controlling transmission in a radiotelephone system".

In North America digital cellular radiotelephone system using multiple access with time division multiplexing (mdvr), known as digital advanced mobile radiotelephone (D-AMPS), has the characteristics defined in TIA/EIA/IS-136 manufacturers Association of telecommunications and the Association of manufacturers of electronic equipment (TIA/EIA). Another digital communication system using multiple access code division of channels with direct modulation sequence (mdcr-RAP), is defined in TIA/EIA/IS-95, and communication system mdcr hopping frequency is determined by the EIA SP 3389 (PCS (personal communication system) 1900). Standard PCS 1900 characterizes variant implementation of the global system for mobile communications (GSM) and is widely used outside of North America, introduced for personal communication systems.

Currently, various organizations on the standard of the international telecommunication Union (ITU), The European Institute for standards in the field of telecommunications (ETSI) and Japan Association of producers and distributors of radio equipment (ARIB). It is assumed that in addition to the voice information system of the next generation will be able to transmit packet data and interact with the network packet data, which are also being developed and are based on common industry standards for data transmission, such as the model interface open systems interconnection (OSI) or the kit Protocol transmission control/Internet Protocol (TCP/IP). These standards have been developed for many years, both in spirit and in fact, applications that use these protocols, easily accessible. The main objective of the networks based on standards is to ensure linkages with other networks. The Internet is a modern the most obvious example of such a standards-based network packet data, aimed at achieving such a goal.

In most of these digital communication systems the communication channels are implemented by means of the frequency-modulated carrier signals at frequencies near 800 MHZ, 900 MHZ, 1800 MHZ and 1900 MHZ. In systems multiple access with time sec the channels (mdcr) each radio channel is divided into a sequence of time intervals, each of which contains a block of user information. Time intervals are grouped in successive frames so that each has a specified duration, and consecutive frames can also be grouped into a sequence of supercarb. Access method (for example, MDR or mdcr) used by the communication system operates depending on how presents user information, in the form of intervals or frames, but all modern methods use the structure of the intervals/frame.

The time intervals assigned to one user, which may not be sequential time intervals on the RF carrier, can be seen as a logical channel assigned to the user. During each time interval specified number of digital bits is transmitted according to a specific method of access (for example, mdcr) used by the system. In addition to the logical channels for voice or data traffic from the cellular radio system also provides logical channels intended for the control messages, such as channels alerts/access message call setup exchanged between the base station and the mobile one hundred the different stations and other remote terminals to synchronize their transceivers with structures frames/interval/bits of base stations. Mainly the bit rate of these different channels do not necessarily coincide, and the length of the intervals in different channels should not be uniform. Moreover, the cellular communication system of the third generation who are in Europe and Japan, are asynchronous, which means that the structure of one base station is not connected in time with the structure of another base station and the mobile station does not know any of the structures in advance.

In such digital communication systems, the receiving terminal must find the reference synchronization signal transmitting terminal to any transfer of information. For communication systems mdcr-RAP finding the reference synchronization signal corresponds to the presence of the boundaries of the data elements, symbols, and frames the return line (for example, a base station - mobile station). This is sometimes called the synchronization signal elements, character and frame synchronization of the return line, respectively. In this context, the frame is simply a block of data that can be independently detected and decoded. Length frames in modern systems usually range from ten milliseconds (MS) to twenty milliseconds. This search synchronization base is in scrambling back line, which are the characteristics of modern communication systems mdcr-RAP.

Mobile station or other remote terminal usually takes a signal that is a superposition (sum) of weakened, dying and distorted copies of the signal transmitted by the base station. The interval limits and frames in a received signal is not known to the mobile station, as well as any specific base station scrambling codes. Thus, the goal of the mobile station is to detect and identify one or more base stations in the adopted noise-like signal (for mdcr-RAP) and identify the used scrambling code.

In order to facilitate synchronization of the remote terminal to the base station and to identify the specific base station scrambling code, in some communication systems, each base station signal includes descrambling part, which may be referred to as channel synchronization (CS), which can synchronize the mobile station to perform a cell search. The present invention improves the efficiency of such synchronization channel in the sense of improving performance and reducing the complexity of mobiloco determine the scrambling code group for the received signal in a digital communication system. The signals in the communication system scribblenauts through respective scrambling codes; scrambling codes assigned to the corresponding scrambling code groups; and identification of the scrambling code groups are encoded in the signals by means of respective sequences of code words with a sign, visible under cyclic shifts, which are S-Hadamard sequences. The method includes the steps of performing a correlation of the received signal with each of the multiple code words; coherent combining the correlation values in accordance with a cyclic shifts of each of the multiple character sequences; and determining the maximum coherently combined correlation to identify the scrambling code group for the received signal.

In another aspect the present invention provides a method for determining the scrambling code group for the received signal in a digital communication system in which signals scribblenauts through respective scrambling codes, scrambling codes assigned to the corresponding scrambling code groups, identity groups, scrambling codes are encoded in the signals posrel the execution phases of the correlation of a received signal with a cyclic shifts of each of the multiple sequences of code words, which are S-Hadamard sequences; combining the correlation values for each of the multiple sequences of code words; and determining the maximum combined correlation to identify the scrambling code group for the received signal.

In another aspect of the present invention a digital radio system, containing at least one transmitter and at least one receiver includes a device in the transmitter is designed to generate a synchronization signal, which includes a version of the S-Hadamard sequences with the sign. S-Hadamard Sequence obtained by the positional scrambling sequence of the Walsh-Hadamard transform using a special sequence having complex elements of constant size. The claimed system also includes a device in the receiver, is designed to evaluate a temporary position and identification data sequence to the adopted version of the synchronization signal.

In another aspect the present invention provides a method for determining the temporal position of the received signal and identifying the sequence of the Walsh-Hadamard transform, is coded is t a work sequence of the Walsh-Hadamard transform and a special sequence, having complex elements constant value, and the sequence of the Walsh-Hadamard transform is a member of the first set of sequences of the Walsh-Hadamard transform. The method includes the steps of forming pieces of a received signal and a special sequence and perform correlation works with each of the multiple sequences of the Walsh-Hadamard transform to identify the sequence of the Walsh-Hadamard encoded in a received signal.

Brief description of drawings

The invention is further explained in the description of specific variants of its implementation with reference to the drawings, which represent the following:

Fig.1 is an example of a hierarchical or multilevel cellular communication system;

Fig.2 is a block diagram of a cellular mobile radiotelephone communication system;

Fig.3 - structure frame/interval/data element and channel synchronization with the primary synchronization code and the secondary synchronization code;

Fig.4 is a block diagram of the method according to the present invention; and

Fig.5 is a block diagram of a method of determining the scrambling code group according to the present invention; and

Fig.6 is a block diagram of another embodiment of a method for determining the scrambling code group according to the present from the S-Hadamard sequence, included in the received signal; and

Fig.8 is a block diagram of the transmitter of the communication system according to the present invention; and

Fig.9A, 9B, 9C is a block diagram of parts of the receivers according to the present invention; and

Fig.10 is an illustration of the use of S-Hadamard sequences of high order.

A detailed description of the preferred embodiments

In this application the invention is described in the context of cell search in a cellular radio system mdcr-RAP. It should be clear that it is presented on the example and that the invention can be applied in many other situations.

Fig.3 illustrates a radio frame duration of 10 MS, which 40960 complex (in-phase and quadrature) data items, divided into sixteen intervals. Thus, each interval includes 2560 data elements that represent ten 256-element characters. This structure frame/interval/data element is a feature of the third generation broadband communication systems mdcr under consideration by the European Institute for standards in the field of telecommunications (ETSI). The radio signal transmitted by a base station in a communication system is the sum advanced and is the ITA's management typically extend through a bitwise or, or unit replacement orthogonal sequence or sequences, such as sequences of the Walsh-Hadamard transform (This is sometimes called m-fold orthogonal manipulation.) The results of the expansion are usually scribblenauts by-bit addition modulo 2 psevdochumoy (PSH) scramblase sequence.

The sync channel contains two parts: a primary synchronization code (DCC) and a secondary synchronization code (VCS), each of which is transmitted once per frame. In Fig.3 synchronization codes PKS and videoconferencing are illustrated as being transmitted simultaneously, but this is optional; the secondary synchronization code can be transmitted in another part of the interval. In one embodiment, the broadband communication system mdcr (W-mdcr) all base stations use the same primary synchronization code, which has a fixed relative position in the same interval (intervals) for all base stations. The example shown in Fig.3, has a primary synchronization code located at the beginning of the interval. The position of the secondary synchronization code may also be fixed (for example, at the beginning of the interval, as shown in Fig.3), but the value of the secondary synchronization code m is th same base station can be transmitted to different values of the secondary synchronization code. However, the length of the 16 sequences (possibly different) values of the secondary synchronization code periodically repeated across consecutive frames transmitted by each base station.

As noted above, the remote terminal such as a mobile station, receives from a transmitter such as a base station, a signal that is the sum of weakened, dying and distorted copies of the signal actually transmitted by the base station. In the remote terminal spacing, and borders frames received signal and scrambling codes used by the transmitter are initially unknown. Aim the remote terminal is to determine the structure of the frame/interval/data item in the adopted noise-like signal and identifying the scrambling code used.

One way to achieve this is to set the synchronization frame, and then directly to identify the scrambling code by performing correlation of the received frame with all the alleged scrambling codes. If the number of candidates is large, it is very difficult and energy-intensive procedure, for example, in the communication system with high carrying capacity, the number of alleged scrambling codes in groups, each of which includes a smaller number of codes, and to encode the identity of the group in the sequence of secondary synchronization codes. Thus, by detecting a sequence of secondary synchronization codes, which can take some or all of the intervals in a received frame or frames, remote terminal defines a small subset of all proposed scrambling codes to which they belong scrambling codes of the base station. Then, the remote terminal may perform a correlation of the received information with each of the more than acceptable number of alleged scrambling codes in the subset to determine the specific scrambling code of the base station. In both of the ways described below, the sequence of secondary synchronization codes are selected so that the identification of the scrambling code group and frame synchronization can be obtained simultaneously.

In the following description of two alternative methods of secondary synchronization codes, which can be modulated, have a length of 256 and are selected from the set of orthogonal codes Golda length 256. The sequence of the primary synchronization codes can also be taken from togai types of orthogonal codes. In fact, generally speaking, the primary synchronization codes and the secondary synchronization codes do not necessarily have to be orthogonal, although usually orthogonality is preferred.

A common first step for the two methods (see Fig.4) is the synchronization intervals and data elements. In the communication system having a channel synchronization, similar to what is proposed in the system W-mdcr with descrambling General primary code synchronization, the remote terminal may ignore the received signal (after removal of the carrier and so on) through the filter, consistent with the primary code synchronization.

This coordinated filter can be implemented using software executed by the processor 180 remote terminal, or using hardware, such as a delay line with taps or shift register. Other communications systems could use other devices or methods provide synchronization for the data elements and intervals.

It is clear that in General there is no need to provide synchronization interval; a receiver could search for a secondary synchronization codes, setting synchronization only on data elements or bits. One of phagemid secondary synchronization codes for multiple selected delays, because the receiver could not have synchronization interval. However, it should be borne in mind that the number of possible start positions without using synchronization interval represents the number of data elements or bits in the frame, not the number of intervals. In the current systems W-mdcr used 40960 data elements in each frame and only sixteen intervals. Thus, in addition to facilitate the detection of the carrier signal descrambling primary synchronization code transmitted in one or more intervals, the network communication system is a clear advantage consisting in the fact that the number of possible positions of the beginning of the frame decreases with the number of data elements in the frame until the number of intervals, including the primary synchronization code.

At the next General step shown in Fig.4, the receiver determines the sequence of secondary synchronization codes and, therefore, the synchronization frame and the identity of the group. In the third stage, also common to both methods is diskriminirovaniya received data using all of the candidates in the code group identified in the previous step.

For proper implementation of stage 1 of the method according to fisicheskii autocorrelation properties. "Good autocorrelation properties are such that the correlation value of the code word or sequence with shifts of this code word or sequence a little, except for the value for the zero shift. Aperiodic properties important in situations in which the code word or sequence is not transmitted continuously, as, for example, in the currently proposed systems W-mdcr, in which the sequence of the primary synchronization codes is only one of nine symbols transmitted in each interval. Because the search of the primary synchronization code agreed upon by the filter affects only the primary synchronization code, occurring in a specific interval, passing through the filter, but not a primary synchronization codes found in previous or subsequent intervals, then it is important aperiodic autocorrelation properties of the primary synchronization code. Good aperiodic autocorrelation properties can be guaranteed by any of the two examples of the methods described below, which are illustrated in Fig.5 and 6.

Method 1

Assume without loss of generality that there are 512 scrambling codes divided into thirty-two groups on the pole the analog synchronization for example, through the sequence of secondary synchronization codes in the frame (step 502 in Fig.5). Assigned code words could be transmitted to the remote terminal or saved in advance in a suitable storage device in the terminal. If the code word C1was just referred to as secondary synchronization code in each frame interval, then by definition of C1the receiver was determined group of scrambling codes (and bronirovanie intervals, if the primary synchronization codes are not transmitted in every frame), and not bronirovanie frames (frame synchronization). Therefore, according to one aspect of the present invention, the version of C1with the token is passed to each of several or all of the intervals in the frame or frames. Characteristic for the interval marks are selected (step 504 in Fig.5) so that the sequence of secondary synchronization codes contained sequence, distinguishable by cyclic shifts and with good periodic autocorrelation properties.

Accordingly, if miis the sign code word C1in the i-th interval, then frame with 16 intervals, transmitted sequence sub>C1, m16C1]

Performing the correlation information received interval with all possible code words C1(step 506 in Fig.5) and coherently combining these correlation values according to the sequence of characters corresponding to all cyclic shifts of the sequence [m1, m2,..., m15, m16] (step 508 in Fig.5), can be defined as a code word With1and phase [m1, m2,..., m15, m16] that maximizes the combined correlation value (step 510 in Fig.5).

It should be clear that in order to coherently combine the values of the correlation information of the interval with a code word, it is necessary to estimate the channel, which includes the determination of the receiver weighting function or impulse response of the communication channel. For coherent digital amplitude modulation and transmission over the fading channel in the system such as W-mdcr this assessment of channel response must be based on known primary code synchronization, for example, by performing the correlation information received interval with known primary code synchronization. Aspects of channel estimation in digital communications systems are described in U.S. patent No. 5768307 in the name of R. Schramm et al, from the method is based on the formation of sequences of members of a small number of different code words C1that is sufficient to uniquely identify each group of scrambling codes (step 602 in Fig.6). Again without loss of generality we can assume that there are 512 scrambling codes divided into thirty-two groups of sixteen codes each. For example, suppose that there are seventeen of code words C1and frames with 16 intervals each. "Alphabet" of seventeen of letters or symbols can generate many sequences of length 16 characters, and you can show that many of these sequences have good periodic autocorrelation and mutual correlation properties. Such ways of constructing a sequence described in the document "Comma Free Codes for Fast Long Code Acquisition", Doc. No. AIF/SWG2-15-6(P), IMT-2000 Study Committee, Air Interface Working Group, SWG2, which was submitted by the company Texas Instruments Inc.

"Good autocorrelation properties are such that the correlation value of the code word or sequence with any of the other code words or sequences and any relative shifts of code words or sequences is not enough. Periodic properties important in situations in which a code word or a sequence of transmitted continuously as, for example, consisting of sixteen characters, repeats from frame to frame. Although the primary synchronization code is only one of the ten symbols transmitted in each interval, and in this sense is not continuously transmitted, however, it is possible for the synchronization intervals that is installed so avoid the search for the secondary synchronization codes in 9/10 of the frame and handle of the secondary synchronization codes as continuous. So if there are any sixteen consecutive intervals in the receiver is known at least character-based cyclic shift of a sequence of sixteen characters.

Of the many possible letter sequences of length 16 letters are selected thirty-two on the basis of their correlation properties for the respective sequence of secondary synchronization codes. As in method 1, the selected sequence can be transmitted to the remote terminal or saved in advance in a suitable storage device in the terminal. However, it should be noted that the sequence generated according to the method 1, as I believe now, have a slightly better correlation properties than the sequence generated according spore code words of "alphabet", consisting of seventeen code words, so that the sequences are different, consisting of a code word sequences, distinguishable by cyclic shifts on the code word, and, consequently, they have a mutually good correlation properties. For example, suppose there are two "letters" a and b, which are mutually orthogonal sequences of length 256, similar to the secondary sync codes, and you must select the sequence of 8 of these "letters". If you start with a sequence AAAAAA, one cyclic shift of the sequence gives a sequence of AAAAAAW, which differs from the original sequence AAAAAA. One sequence, which are not distinguishable by cyclic shifts on a code word that represents AWAWAW and the other AAAAAAAA. Regarding the latter, it should be clear that all cyclic shifts of the same, in case the first is some cyclic shifts are the same. Of course, it should be clear that a shift in one sequence length (i.e., the shift in number of characters) again gives the original sequence that does not indiscernible sequence cyclic shifts on the code word is Oh AWWWW, which for convenience may be called last.1, and WAAAW, which for convenience may be called last.2. Table 1 shows the number of positions of the sequence in which the input sequence and each of the shifted sequence is consistent, i.e. have the same "letter":

From this table you can see that th.2 is better autocorrelation properties than pet.1, because, as noted above, good autocorrelation properties are such that the correlation value of the code word or sequence with shifts of this code word or sequence a little, except for the value for the zero shift. For sequences that are not distinguishable by cyclic shifts on the code word, the number of matches could be equal to 8 (the maximum) at least one non-zero shift. It should be clear that the number of matches associated with the value of the correlation so that the correlation (or auto-or cross-correlation) is usually defined as the number of matches less than the number of mismatches.

Cross-correlation between th.1 and PEFC.2, i.e. the number of positions of the sequence in which th.1 and PEFC.2 have the same "letter", is it 2:

A good set of code words such that when it is unlikely to mistake the one code word for another and/or shift one or the other code words. Similarly, information received interval correlated with all possible sequences of code words for all shifts (step 604 in Fig.6).

It should be noted that the code word C1no sign, as in method 1, and it is therefore possible incoherent combining the correlation values of accepted intervals with their corresponding code words (step 606 in Fig.6). For example, let Ci=(Security standardsi) is the correlation between Riadopted by the information in the i-th interval, and the magnitude of the SSCiis the i-th secondary code synchronization in a hypothetical sequence of secondary synchronization codes. Then the sum of the values of Citaken by i, is the correlation between the hypothetical sequence and accepted information, but because of various Riare unknown and different fading or other disturbances in the transmission, in the absence of estimates of the channel you want a non-coherent combining. In other words, the criterion is the sum of the squares of the values Withi, statesupervised i works Withiand complex conjugate values of ai. When using method 1 for coherent integration is necessary because the marks mishould be kept, and when using method 2 can be used either coherent combining or non-coherent combining.

Accordingly, if Ciis a secondary code synchronization in the j-th interval, the transmitted sequence of secondary synchronization codes for frame having sixteen intervals, will be the following:

[C1With2,..., C15C16]

Determination of the maximum correlation values obtained after performing the correlation information received interval with all the possible sequences of secondary synchronization codes on all shifts, identifies the synchronization of frames and the sequence [C1With2,..., C15C16], which identifies a group of scrambling codes (step 608 in Fig.6).

As noted above, the primary and secondary synchronization codes may be orthogonal codes Golda length 256. Such synchronization codes are used in communication systems W-mdcr that are on the review of the European Institute for standards in the area of the telly primary synchronization codes in the currently proposed systems W-mdcr is selected from a set of orthogonal codes Golda 256, so the selected sequence has the highest quality factor, which is defined as the squared values of the aperiodic autocorrelation zero delay divided by the sum of the squares of the values of the aperiodic autocorrelation with a non-zero delay. Alternative quality factor could be defined as the maximum peak value of the autocorrelation function is not in the phase.

One aspect of such codes and codes for various other types in this respect is that the autocorrelation properties of orthogonal codes Golda is not necessarily the best. Although the autocorrelation properties of the sequence of codes Golda selected by this criterion, satisfactory, it is desirable to find the sequence with the best properties.

In addition, the use of orthogonal codes Golda increases the complexity of the receiver, because in real-time during processing of the incoming signal, the receiver must perform a variety of correlations for 256 data elements in each interval. Well-known sequence of the Walsh-Hadamard transform can be effectively decorrelate using fast Walsh transform (FWT) with simple prienne the processor of the fast Walsh transform", included in this description by reference. The sequence of the Walsh-Hadamard have structural properties that allow you to correlate the received sequence with the sequence of the Walsh-Hadamard transform with much less complexity than the correlation method "brute force". The results of the operation of the fast Walsh transform is essentially identical to the correlation of the received sequence with all sequences of the Walsh-Hadamard transform of a given length.

In addition, for applications such as in the currently proposed systems W-mdcr, it is necessary to use only a subset of the family of sequences of the Walsh-Hadamard transform, and therefore the interest is only a subset of the results of the fast Walsh transform. Fast Walsh transform is an efficient and complete conversion would perform unnecessary operations. With careful choice of the set of all sequences of the Walsh-Hadamard transform of decorrelation can be performed using fast Walsh transform is of smaller order than the fast Walsh transform. Therefore, from the point of view of complexity, are suitable Hadamard sequence. However, posledovatelnoy target cell search.

In principle it is desirable multiple orthogonal sequences, of which at least one is aperiodic autocorrelation properties similar to or better than that of the sequence of codes Golda described above, which could serve as a sequence of primary and secondary synchronization codes. It is also desirable family of sequences that can be effectively decorrelate in the receiver. These objectives can be achieved through a set of orthogonal sequences based on the sequences of the Walsh-Hadamard transform, but with a better autocorrelation properties. In the present description such sequences are called S-Hadamard sequences.

In accordance with one aspect of the invention, each sequence of the Walsh-Hadamard transform is multiplied on positions on a special complex S-sequence, with the components of the singular values. Special S-sequence is carefully chosen so that the members of the resulting set S-Hadamard sequences have good autocorrelation and intercorrelation properties due to the S-sequence. The building sequences divine access to the radio system" and in U.S. patent No. 5550809 in the name of G. Bottomley et al. on "Coding multiple access using folded sequences in mobile radio systems". These patents are included in this description by reference.

Suppose Hmmatrix of Walsh-Hadamard dimension M x M, normalized so that the top row of the matrix is the sequence of all ones. The sequence of the Walsh-Hadamard transform are defined by M rows of this matrix, and the values of the elements in Hm(component sequence) is equal to +1 or -1. The matrix Hmis formed in the usual way according to the following expression:

where H1=[+1]. This so-called Hadamard matrix Sylvester-type.

Swapping rows or columns in the matrix Hmor multiplication of any row or column by -1 gives the Hadamard matrix. The following criterion for the selection of sequences among rows fair for matrices Sylvester-type and it can change a simple way for other types of Hadamard matrices. The following description uses a matrix of Sylvester type in the examples without any loss of generality.

Let [hi,0hi,1,..., hi,m-1] I a Hadamard sequence, and let S=[s0, s1

which can be considered as the result of scrambling transmitter codeword of the Walsh-Hadamard transform with S-sequence.

Cross-correlation between the i - and j - S-Hadamard sequences is determined by the following expression:

which is equal to M, if i=j and equal to zero if this equality is violated, because the original sequence of the Walsh-Hadamard transform are mutually orthogonal. Therefore, the S-Hadamard sequence is also orthogonal.

It should be noted that the first row in the matrix Hmis a sequence of all ones, and, consequently, the corresponding S-Hadamard sequence itself is a special S-posledovatelnostyu, which follows from:

Thus, if we choose S to be the sequence so that it had a good aperiodic autocorrelation properties, the set of orthogonal S-Hadamard sequences will have at least one member, which also has these good autocorrelation properties.

There are several ways strereotype, as the autocorrelation sequence properties of gold, and which will be used in the currently proposed systems W-mdcr. One simple way is to select the currently proposed sequence of the primary synchronization codes as a special S-sequence. Then, as noted above, if as the basis for a new sequence of the primary synchronization codes selected sequence of the Walsh-Hadamard transform, consisting of all ones, then one of the S-Hadamard sequences is a special S-sequence and the new sequence of the primary synchronization codes.

Another way is to select one of the sequences in the so-called complementary pair of sequences, which are described in the publication by S. Z. Budisin, entitled "New Complementary Pairs of Sequences", Electronics Letters, vol.26, no.8, pp.881-883 (June 21, 1990), as well as: S. Z. Budisin, "New Multilevel Complementary Pairs of Sequences", Electronics Letters, vol.26, no.22, pp.1861-1863 (Oct.25, 1990). Both these publications included in the present description by reference. Such sequences, as is known, include sequences with good autocorrelation properties. Generally speaking, the complementary pair of th is s equal to zero for all nonzero delays. However, for this application, you need only one member of a complementary pair.

As explained in the publications Budisin, cited above, the actual multi-level complementary to the sequence of anand bncan be generated according to the following expression:

where(i) - Delta function Kronecker;

n is the number of iterations;

n1, 2,.... N-1;

Wnthe coefficients having values +1

or -1;

Snis an arbitrary positive delay;

i - an integer representing the time scale of

The actual multilevel complementary sequences can also be generated, as described in publications Budisin, according to the following expression:

again, where(i) - Delta function Kronecker;

n is the number of iterations;

n1, 2,... N-1;

An- valid parameters;

Snthe arbitrariness of omplementary pairs of sequences of 256 binary elements, which are generated according to the algorithm described in publications Budisin, cited above. Table 3 represents the comparison of the quality factor and the maximum amplitude peak for the sequence of the primary synchronization codes, which is orthogonal sequence Golda to complementary sequences that are optimized relative to the quality factor (QC) and complementary sequences, optimized with respect to maximum amplitude peak.

The table shows that in fact there are sequences with the best coefficients of quality (or quality factor QC, or the maximum peak amplitude) than the primary synchronization code, in the form of an orthogonal code Golda.

As a particular example, sequences complementary pairs, which could be appropriate for the currently proposed system W-mdcr, you can successfully use the following sequence Snand Wnin the algorithms described in publications Budisin, cited above:

[S1, S2,..., S8]=[1, 2, 8, 64, 4, 128, 32, 16]

[W1, W2,..., W8]=[1, 1, 1, 1, 1, -1, 1, 1],

to obtain the latter is of egovernance.

As another particular example, sequences complementary pairs, which could be appropriate for the currently proposed system W-mdcr, you can successfully use the following sequence Snand Wnin the algorithms described in publications Budisin, cited above:

[S1, S2,..., S8]=[32, 1, 16, 2, 4, 128, 8, 64]

[W1, W2,..., W8]=[1, 1, 1, 1, 1, -1, 1, 1],

in order to obtain a sequence [an(i)], where n=8 and i0, 1,..., 255 having the smallest maximum correlation peak at zero delay found for such sequences.

Many sequences among complementary pairs of sequences have better odds of quality or better maximum amplitude peak, codes than gold, and therefore, such sequences can be successfully used as a special S-sequences. Complementary pairs of sequences are particularly suitable for this application because of their length are consistent with the lengths of the sequences are Walsh-Hadamard Sylvester-type, i.e. they are integer powers of two.

Generally speaking, can be sporny, which do not correspond to the sequences of the Walsh-Hadamard transform. Thus, such sequences may not be used without modification (and, hence, the modified correlation properties).

Multiplication on the positions of the sequences of the Walsh-Hadamard transform and a special S-sequence destroys the structural properties of the sequences of the Walsh-Hadamard transform and provides effective decorrelation by means of fast Walsh transform. However, while the received signal in the form of the adopted comprehensive r'-sequence, which is determined by the expression:

r’=[r’0, r’1, ..., r’M-1],

the receiver can, as a first step to multiply r' positions on the complex conjugate of the value of the special S-sequence to form an r-sequence, defined by the expression:

which can be considered as the result of diskriminirovaniya receiver sequence of the Walsh-Hadamard transform on the basis of the S-sequence. Then r is a sequence can be correlated with interest the sequences of the Walsh-Hadamard transform, for example by using a fast Walsh transform to nadpruhem sequences of length M in the General case takes on the order of M2operations. When using S-Hadamard sequences correlation r-sequence requires only order Mlog2M operations, since it can be used quickly convert Walsh. Of course, there may be circumstances in which it is useful to define the adopted S-Hadamard sequence by the simple method of performing the correlation of the received signal with the alleged S-Hadamard sequences.

Summing up what is illustrated in Fig.7, the preferred method of determining in General if the sequence of the Walsh-Hadamard transform, which is encoded S-Hadamard sequence r, included in the received signal r', i.e., for example, as a primary synchronization code or a secondary synchronization code, includes the following steps, which can be performed in the receiver or hardware, for example, in the form of a dedicated integrated circuit, or by using software executed by a processor of the receiver:

1. To descrambler.html adopted r'-sequence, using special S-sequence in order to obtain r (step 702).

2. To identify a received codeword of the Walsh-Hadamard transform, such as the Hadamard sequence can be obtained by multiplying, as explained above. Special S-sequence can be either transmitted to the receiver, for example, in the form of S-Hadamard sequence based on the above-mentioned single sequence of the Walsh-Hadamard transform, or S-sequence candidates can be stored in the receiver or locally generated it another way.

As noted above, the sync channel in the currently proposed communication systems W-mdcr can use only a subset of all possible sequences of the Walsh-Hadamard transform of length M, where M is identified with the number of intervals in the frame. In the above method 1, the number of members of the subset is only in the number of scrambling code groups (for example, thirty-two). In the example illustrating the method 2, it is necessary seventeen sequences. Given the need in the sequence that should be used as the primary synchronization code, a subset of which is included or thirty-three (method 1) or eighteen (method 2) sequences of length 16, it would be useful for illustrative system. Next, we describe the subset of sequences with the cardinal number with degree two, and then the General case is the length of the sequences, and N is the number of sequences used from M sequences. Also suppose M and N are integer powers of two and L=M/N. Then let N used sequences is defined as:

for i=0, 1, ..., N-1 for any k=0, 1,..., L-1, that is, the selected sequence of the Walsh-Hadamard transform is taken as each L-th row in the matrix Hmlines starting with k. Then these selected sequences scribblenauts with a special S-sequence to change their autocorrelation properties. A subset of the sequences of the Walsh-Hadamard transform is preferably selected so that the receiver could use N-point fast Walsh transform.

Analysis of the selected sequences are Walsh-Hadamard shows that each of the N sequences of length M is a concatenation of N copies of a subsequence S' with the sign of length L. S'Is a Subsequence is the same for all sequences of the Walsh-Hadamard transform, but the configuration of the characters are different, as can be seen from the following:

where h'i,j- sign in front of the j-th copy of S'is a subsequence in the i-th sequence of the Walsh-Hadamard transform.

Depending on k S'-podposite the I-Hadamard matrix of order N. This implies, for example, the following modification of the method illustrated in Fig.7, which can be implemented in the receiver, when the number of sequences N and the length of the sequence M are integer powers of two:

1. To descrambler.html adopted comprehensive r'-sequence using a special S-sequence to obtain an r-sequence (step 702);

2. To perform N successive correlations for N consecutive subsequences of length L sequence r with S'is a subsequence to obtain r-sequence of length N (step 704).

3. To perform the N-point fast Walsh transform for r-sequence for identification of the received sequence of the Walsh-Hadamard transform of length N (step 704). It should be noted that steps 1 and 2 can be combined to obtain a simpler modification of the method illustrated in Fig.7, comprising the stages of:

1. To perform N successive correlations for N consecutive subsequences of length L adopted comprehensive sequence r' short sequences S'1,..., S'Nto obtain a sequence r of length N (step 702).

2. To perform N-aunts Walsh-Hadamard transform of length N (step 704).

Short sequence S'icorresponds to multiplication on the positions of the i-th sub-segment S of length L in S'. Thus, diskriminirovaniya and formation of partial correlations are performed at the same time.

If the number sequence is not equal to a power of two, as in the examples above, you can perform a 32-point fast Walsh transform and ordinary correlation, for processing the subset of the thirty-three members, and you can perform a 16-point fast Walsh transform and two conventional correlation processing of a subset of the eighteen members. Used sequences of length 32 and a length of 16 must be selected, as described above, and an additional one or two sequence can be any sequence that is not included in those thirty-two or sixteen sequences.

An alternative to the number of sequences that are not a power of two, for example forty-eight (instead of, say, 256), the receiver can perform the above steps 2 and 3 twice: once with N=32 and once with N=16 (S', L and k will also vary.) 32+16 Sequences must be carefully selected according to the criteria mentioned above, and do not sow any number is the sum of integer powers of two. You can also use the fast Walsh transform of a smaller order, which is larger than necessary, for example, a 64-point fast Walsh transform, and not just use sixteen resulting from the correlation values.

As shown above, there are many ways of action in the case when N is not a power of two.

Fig.8 depicts a block diagram of the transmitter 800 communications system according to the present invention. Generator 802 generates the appropriate special S-sequence which is fed to the generator 804 to generate a set of code words S-Hadamard transform. Generator 804 may include a device for generating, for example, a recursive way, sets, or subsets of the sequences of the Walsh-Hadamard Sylvester-type length M, and a multiplier for forming works special S-sequence and the members of the set or subset of the sequences of the Walsh-Hadamard transform of length M Alternative generator 804 may include the appropriate storage device for storing the members of the set or subset of the sequences of the Walsh-Hadamard transform of length M, and a multiplier. Specific members of the set or podborovye, provide generator 808, which may be a storage device that stores the specified identification data groups. The sequence of selected code words S-Hadamard transform, which can be the primary code synchronization and secondary synchronization codes, as described above, is fed to the modulator/schema Association 810 for the formation of a transferred ultimately signal, i.e. the signal in the transceiver 160 of the control channels (see Fig.2). Modulator/join scheme 810 may also receive signals corresponding to other channels of communication, or information which is combined with the sequence of selected code words S-Hadamard transform.

It is clear that the functions of most of the devices illustrated in Fig.8 may be performed by module 130 for processing and managing the base station (see Fig.2). It is also clear that the generators 802, 804 may be replaced by an appropriate storage device for storing the set or subset of code words S-Hadamard transform of length M in Addition, generators 802, 804, 808, and a selector 806 may be replaced by an appropriate storage device for storing one or more sequences selected code words S-Hadamard transform.

Fig.9A, 9B, 9C depict block-scheme is SNA r'-sequence is served in decorrelator 902, which generates a correlation of r'sequences with members of the set of code words S-Hadamard transform, which is given a suitable generator 904, which can be a simple storage device for storing code words, as noted above with reference to Fig.8. The output signal of decorrelator 902 represents the value or other criteria, suitable for tasks like mobile search, for example, the display identification data code words S-Hadamard in the received sequence. Although it may perform the decorrelation method depicted in Fig.9A, it is not possible to achieve the greatest efficiency possible when using code words S-Hadamard transform.

Fig.9B illustrates a fragment of a more effective receiver 900', adopted in which r'is a sequence fed into the multiplier 910, which forms the product of the r'-sequence and a special S-sequence produced by a suitable generator 912. "Diskriminovanej" r-sequence generated by the multiplier 910, filed decorrelator 914, which correlates r-sequence with members of the set or subset of the sequences of the Walsh-Hadamard transform of length M, as described above. The sequence of Walsh is a passive generation of sequences, or mass storage device to provide them with a simple search. It is clear that decorrelator 914 and the generator 916 can be successfully replaced by a processor, implements a fast Walsh transform. As shown in Fig.9A, the output signal of decorrelator/devices fast Walsh transform is a value or other criteria, suitable for tasks like mobile search, such as display identification data code words S-Hadamard in the received sequence.

Fig.9B illustrates a fragment of the receiver 900, which includes decorrelator 920 and decorrelator 922. In one embodiment, the receiver 900" decorrelator 920 forms a sequential partial decorrelation accepted r'sequences with many short sequences that have length smaller than M, and this corresponds to the multiplication of positions of special S-sequence and subsequence member of many sequences of the Walsh-Hadamard transform of length M. the Results of this process of decorrelation served in another decorrelator 922, which correlates successive partial decorrelation with members of many sequences of the Walsh-Hadamard transform, which include this podposledovatelnostei signal represents a value or other criteria, suitable for tasks like mobile search, i.e. display identification data code words S-Hadamard in the received sequence.

In another embodiment, the receiver 900" decorrelator 920 generates a partial sequential decorrelation "descrambling" adopted r-sequence with a subsequence of the sequence of the Walsh-Hadamard transform of length M is a Multiplier for forming the product (r-sequence) adopted r'sequences and special S-sequence in Fig.9B is omitted for clarity. Then the results obtained by decorrelation 920, correlated with decorrelation 922 with members of many sequences of the Walsh-Hadamard transform, which include this subsequence. As mentioned above, decorrelator 920, 922 can be replaced by a device of the fast Walsh transform, etc.

It is clear that the present invention can be advantageously used in communication systems, such as system sh-mdcr described ARIB, which uses the masked characters, in addition to the communication system, such as system sh-mdcr described ETSI, which uses the primary synchronization code and the secondary synchronization codes in the channel synchronization. ("Maskirovany which is masked or blocked for this character). As noted above, the primary synchronization code and the secondary sync codes are added to the signal return line (from the base station to the remote terminal) after the merger and the other scrambling signal components of the reverse link, i.e., the traffic information for the various remote terminals. The masked characters in the currently proposed system W-mdcr described ARIB, generally speaking, correspond to the primary code synchronization and secondary sync codes in the ETSI system, but the masked symbols are multiplexed in time with the components of the feedback signal line. For example, masked characters may from time to time be inserted in the channel traffic.

As another example, let each row in the matrix Hmis the sequence of the Walsh-Hadamard transform of length M=2kwith elements +1/-1. If should be submitted only a subset of the M sequences of the Walsh-Hadamard transform, for example N sequences, the receiver with fast Walsh transform computes M-N unnecessary correlations, as noted above. However, if N sequences selected in a suitable manner, the receiver can perform a quick conversion of the 2 and let L=M/N. Suppose that N sequences should be chosen as each L-th row of the matrix Hmstarting, for example, from row j. The analysis of these N sequences shows that each sequence contains N copies of S'-subsequences of length L with a sign, which are the same for all the selected N sequences. Copies of S'-subsequences with the sign in the matrix form the matrix of Walsh-Hadamard Sylvester-type of order n

As a numerical example, suppose that M=16, N=4, L=16/4=4 and j=2. Then, N=4 sequences selected from the matrix of Walsh-Hadamard transform H4are as follows:

string 2=[1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1]

string 6=[1, -1, 1, -1, -1, 1, -1, 1, 1, -1, 1, -1, -1, 1, -1, 1]

string 10=[1, -1, 1, -1, 1, -1, 1, -1, -1, 1, -1, 1, -1, 1, -1, 1]

string 14=[1, -1, 1, -1, -1, 1, -1, 1, -1, 1, -1, 1, 1, -1, 1, -1]

or

string 2=[+S' +S' +S' +S']

line 6=[+S'- S' +S'- S']

line 10=[+S' +S'- S'- S']

line 14= [+S'- S'- S' +S'],

where the subsequence S'=[1, -1, 1, -1]. The corresponding matrix of characters is determined as follows:

You may notice that the sign matrix is a matrix of Walsh-Hadamard Sylvester-type 4 order, that is, N2.

The above-mentioned structure predpolagaete length L of the received sequence, and then perform N-point fast Walsh transform.

Thus, with the degree of complexity, defined as NL+Nloq2N complex additions, can be obtained all N values of correlation. This should be compared with NM operations required in case if should be a simple correlation for the total number of sequences.

Unfortunately, these sequences are Walsh-Hadamard have bad auto and mutually correlation properties. However, these sequences can be modified accordingly, as explained above, to obtain a family of codes with good auto - and mutually correlation properties and low complexity detection.

New sequence receive by "scrambling" (i.e. the change of the sign positions of the element) sequences of the Walsh-Hadamard transform using special S-sequence with a fixed length of M, the resulting set of sequences preserves the property of orthogonality of the sequences of the Walsh-Hadamard transform, regardless of the choice of S, provided that all items have unit size. Also welcome is eljnosti by multiplying the S-sequence, and then performing a fast Walsh transform (see, for example, Fig.9B).

Thus, code can be generated in the transmitter by selecting matrix of Walsh-Hadamard transform, as mentioned above, to obtain the basic sequence of the Walsh-Hadamard transform, and by scrambling each selected sequence with a special S-sequence. The resulting sequences contain multiple orthogonal codes that can be used, for example, the sync channel.

The receiver can descrambling adopted the sequence by multiplying by a special S-posledovatelnosti, run-N correlations subsequent sub-segments of length L descrambling sequence S'-sequence, and performing N-point fast Walsh transform to obtain the final result. Thus, the number of required operations is approximately M+NL+Nloq2N complex additions. In addition, given that the first two stages of processing in the receiver can be merged, you will only need NL+Nloq2N complex additions.

As the number of the I, in the proposed method will then be developed fifteen values that will not be used. Select every eighth sequence of the Walsh-Hadamard matrix H8Walsh-Hadamard transform of order 256. When using the inventive method requires 256+256+325=672 complex collapses. For the main set of all sequences without patterns quickly convert Walsh would need 17256=4352 complex collapses. If you combine the first two stages of processing, the receiver will only need 256+325=416 operations, i.e. savings of more than 10 times. Thus, with complexity less than two correlation length 256, get all seventeen of the correlation values (and fifteen unused).

As noted above, there is no need to explicitly generate or store the sequence with which to perform the correlation in the receiver (except for S - and S'-sequence), because the structure of the codes embedded in the procedure of the fast Walsh transform. For the main set of all sequences or receiver that does not use a fast Walsh transform should also take into account strong correlations.

Methods 1 and 2 described above in the context of the full use of the S-Hadamard sequences, for example, each of the primary synchronization code and/or secondary synchronization code is a complete S-Hadamard sequence. It is clear that this is not a mandatory requirement. Indeed it may be useful to split the S-Hadamard sequence fragments, send these fragments in the same way, what was described above for integer sequences, for example, time intervals between fragments, and then connect the received fragments into a complete S-Hadamard sequence for processing.

For example, the communication system having frames, each of which has sixteen positions of the secondary synchronization code of 256 bits or data elements, could use a 16-element sequence from the S-Hadamard sequences of length 256 (which may or may not be mutually different and/or modulated), as described above, or the system could use the 16 fragments of the S-Hadamard sequence of length (16256). S-Hadamard Sequence of higher order in this example has a length of 4096 (that is, 212) bits or data elements, and so the example to represent the identity of the scrambling code group of the base station.

Then the transmitter system W-mdcr could discretely send fragments of the S-Hadamard sequence of higher order as symbols of the secondary synchronization codes (possibly non-orthogonal). This is illustrated in Fig.10, which depicts the S-Hadamard sequence, divided into 16 fragments of length 28, 1, 2,..., 16, which are inserted in the transmitted signal in the form of secondary synchronization codes with included time intervals (Although the time intervals between the secondary synchronization codes are identical, it is clear that in the General case it is not necessary). As noted above, the transmitter can be performed essentially as illustrated in Fig.8.

To benefit from the use of the above-described S-Hadamard sequences it is only necessary that the receiver knew or was able in some way to determine the location of the fragments in its signal. In the currently proposed systems W-mdcr location of the fragments can be known, if the fragments are referred to as secondary synchronization codes or some other known data item interval. PR-sequence Dakar high order, but not the original fragment, as illustrated in Fig.10 sequence fragments 3, 4,..., 16, 1, 2.

The receiver collects the fragments and identifies the S-Hadamard sequence as described above, for example, multiplying them by the corresponding cyclic shifts of the sequences used to generate the S-Hadamard sequence of high order (see step 702 in Fig.7). For example, a special sequence may represent an orthogonal code Golda length 212. Then, the receiver performs a correlation either by direct calculation or by means of fast Walsh transform, collected the fragments in the order specified by descrambling, using members of the set S-Hadamard sequences of high order to identify the adopted member (see step 704 in Fig.7). As noted above, the receiver can be performed, as shown in any of Fig.9A, 9B, 9B.

Using sequences of higher order has a number of potential advantages, including the simplicity of finding sequences with "good" properties. Also it should be clear that instead of using 16 slices one S-posledovatelei Hadamard length of 2048 or four pieces of each of the four S-Hadamard sequences of length 1024, and so on In addition, it is clear that the receiver can start the process of diskriminirovaniya and identification of S-Hadamard sequence of high order as receiving fragments, through the use of fragments of the sequences and fragments of the members of the set S-Hadamard sequence of a high order. Because the sequence of high order can be long, it may be best not to wait until you have accepted all of the fragments.

The communication system or the receiver according to the present invention has many advantages. You can choose a periodic or aperiodic, auto or mutually correlation properties of at least one sequence by a suitable choice of the S-sequence. Synchronization intervals in communication systems such as communication systems W-mdcr, facilitated because can be selected sequence, providing better results than the primary synchronization code based on the code Golda, by proper choice of the special S-sequence. The receiver can use an effective fast Walsh transform. Fast Walsh transform of a smaller size can be used by the receiver when the number of ISPA. Such an effective implementation of the receiver suitable for devices powered by batteries.

Professionals should be clear that the invention can be implemented in other specific forms without changing its essence. Therefore, the above-described embodiments of shall in all respects be considered as illustrative and not restrictive.

Claims

1. The method of determining the scrambling code group for the received signal in a digital communication system in which signals scribblenauts through respective scrambling codes, scrambling codes assigned to the corresponding scrambling code groups, identity groups, scrambling codes are encoded in the signals by means of respective sequences of code words with a sign, visible under cyclic shifts on the code word, and the method includes the steps of: performing a correlation of the received signal with each of the multiple code words and code words are S-Hadamard sequences, coherent combining the correlation values in accordance with a cyclic shifts of each of the multiple character sequences and determine the IHO signal.

2. The method according to p. 1, characterized in that each sequence of code words with the sign corresponds to the frame of the received signal, and determining the maximum coherently combined correlation identifies the beginning of a frame.

3. The method of determining the scrambling code group for the received signal in a digital communication system in which signals scribblenauts through respective scrambling codes, scrambling codes assigned to the corresponding scrambling code groups, identity groups, scrambling codes are encoded in the signals by means of respective sequences of code words, distinguishable by cyclic shifts on the code word, comprising the steps: performing a correlation of the received signal with a cyclic shifts of each of the multiple sequences of code words, in which code words are S-Hadamard sequences, combining the correlation values for each of the multiple sequences of code words and determine the maximum combined correlation to identify the scrambling code group for the received signal.

4. The method according to p. 3, characterized in that each sequence of code words with the Alo frame.

5. The method according to p. 3, wherein the correlation values are combined coherently.

6. The method according to p. 3, wherein the correlation values are combined decoherence.

7. Digital radio system having at least one transmitter and at least one receiver containing means in the transmitter is designed to generate a synchronization signal, which includes a version of the S-Hadamard sequences with the sign in which the S-Hadamard sequence correspond to the members of the first set of sequences of the Walsh-Hadamard transform, scrambled for positions using a special sequence having complex elements constant value, means in the receiver is designed to evaluate a temporary position and identification data sequence adopted version of the synchronization signal.

8. The system under item 7, characterized in that the evaluator descramble the final version on the basis of a special sequence and performs correlation descrambling adopted version with members of the first set of sequences of the Walsh-Hadamard transform to identify the identity of the sequence.

9. The system under item 8,

10. The system under item 7, characterized in that the evaluator performs a correlation of the received version of the S-Hadamard sequences to identify the identity of the sequence.

11. The system under item 7, characterized in that the evaluator descramble the final version on the basis of a special sequence, forms a sequential partial decorrelation descrambling adopted version subsequence member of the first set of sequences of the Walsh-Hadamard transform and performs correlation of sequential partial decorrelate with members of the second set of sequences of the Walsh-Hadamard transform, and the members of the second set have a length smaller than the length of the members of the first set.

12. System on p. 11, characterized in that the evaluator performs the correlation of sequential partial decorrelate with members of the second set using the fast Walsh transform.

13. The system under item 7, characterized in that the assessment tool forms a sequential partial decorrelation of the received version with many short sequences and correlates of sequential partial decorrelate with members of the second set by posledovatelem length members of the first set, and short sequences correspond to multiplication by the positions of the sequences and subsequences member of the first set.

14. System on p. 13, characterized in that the evaluator performs the correlation of sequential partial decorrelate with members of the second set using the fast Walsh transform.

15. The system under item 7, characterized in that the special sequence is a sequence of orthogonal codes Golda.

16. The system under item 7, characterized in that the special sequence is one of a pair of complementary sequences of code words.

17. The method of determination of the temporal position of the received signal and identifying the sequence of the Walsh-Hadamard encoded in the form of S-Hadamard sequence included in the received signal, in which the S-Hadamard sequence is the product of a sequence of Walsh-Hadamard transform and a special sequence having complex elements constant value, and the sequence of the Walsh-Hadamard transform is a member of the first set of sequences of the Walsh-Hadamard transform, comprising the steps: forming compositions according to the positions taken is of egovernance Walsh-Hadamard transform to identify the sequence of the Walsh-Hadamard transform, encoded in a received signal.

18. The method according to p. 17, wherein the work items correlated with members of the first set based on the fast Walsh transform.

19. The method according to p. 17, wherein the work items correlated by forming successive partial decorrelate work positions subsequence member of the first set of sequences of the Walsh-Hadamard transform and by performing a correlation of sequential partial decorrelate with members of the second set of sequences of the Walsh-Hadamard transform, and the members of the second set have a length smaller than the length of the members of the first set.

20. The method according to p. 17, characterized in that the successive partial decorrelation correlated with members of the second set using the fast Walsh transform.

21. The method according to p. 17, wherein the work items correlated by forming successive partial decorrelate work positions with many short sequences and by performing a correlation of sequential partial decorrelate with members of the second set of sequences of the Walsh-Hadamard transform, precista, and short sequences correspond to multiplication by the positions of the sequences and subsequences member of the first set.

22. The method according to p. 21, characterized in that the successive partial decorrelation correlated with members of the second set using the fast Walsh transform.

23. The method according to p. 17, characterized in that the special sequence is a sequence of orthogonal codes Golda.

24. The method according to p. 17, characterized in that the special sequence is one of a pair of complementary sequences of code words.

25. The method of sending identification data of the scrambling code group transmitted signal in a digital communication system in which signals scribblenauts through respective scrambling codes and scrambling codes assigned to the corresponding scrambling code groups, comprising the steps: providing at least one S-Hadamard sequence and encoding identification data groups, scrambling codes in the transmitted signal as a sequence of S-Hadamard sequences with a sign, visible under cyclic shifts of the code correspond to the frame of the transmitted signal.

27. The method of sending identification data of the scrambling code group for the transmitted signal in a digital communication system in which signals scribblenauts through respective scrambling codes and scrambling codes assigned to the corresponding scrambling code groups, comprising the steps of: providing multiple code words S-Hadamard transform and encoding identification data groups, scrambling codes in the transmitted signal as a sequence of code words S-Hadamard, distinguishable by cyclic shifts on the code word.

28. The method according to p. 27, wherein the sequence of code words S-Hadamard transform corresponds to a frame of the transmitted signal.

29. The signal generator in the transmitter, comprising a generator of special sequences, which generates a sequence with complex elements constant value, the generator S-Hadamard sequences, which takes a special sequence and which generates at least one S-Hadamard sequence based on a special sequence, and S-Hadamard sequence correspond to the respective members of the many posledovatelem identification data, which generates identification information of the scrambling code group, the selector, which selects the S-Hadamard sequence generated by the generator S-Hadamard sequences, on the basis of the identification data groups, scrambling codes, the pattern of Association that unites the S-Hadamard sequence selected by the selector, with the information signal to form a combined signal.

30. The signal generator by p. 29, characterized in that the generator of special sequences includes a storage device from which sampling is a special sequence.

31. The signal generator by p. 29, characterized in that the generator of the S-Hadamard sequences includes a processor that recursively generates sequences of the Walsh-Hadamard transform, and the multiplier, which produces works of a special sequence and sequences of the Walsh-Hadamard transform, generated by the processor.

32. The signal generator by p. 29, characterized in that the generator of the S-Hadamard sequences includes a storage device that stores sequence of the Walsh-Hadamard transform, and the multiplier that generates the special works on the PRS signals on p. 29, characterized in that the generator identification data includes a storage device from which you are fetching the identity of the scrambling code group.

34. Device for use in determining the scrambling code group for the received signal in a digital communication system in which signals scribblenauts through respective scrambling codes, scrambling codes assigned to the corresponding scrambling code groups, identity groups, scrambling codes are encoded in the signals by means of respective code words containing the generator code words S-Hadamard transform, which generates at least one code word S-Hadamard transform on the basis of a special sequence, and the code word S-Hadamard correspond to the respective members of the set of all sequences of the Walsh-Hadamard transform, scrambled for positions using a special sequence, and decorrelator forming, at least one correlation of the received signal, at least one code word S-Hadamard generated by the generator code words S-Hadamard transform.

35. The device according to p. 34, characterized in that the generator least one code word S-Hadamard transform.

36. The device according to p. 34, characterized in that decorrelator includes primary decorrelator, which generates serial correlation of the received signal with many more short sequences that correspond to multiplication by the positions of the sequences and subsequences member of many sequences of the Walsh-Hadamard transform, and the secondary decorrelator that generates correlation consistent correlations with the members of the set of all sequences of the Walsh-Hadamard transform, which include this subsequence.

37. The device according to p. 36, characterized in that the secondary decorrelator is the processor fast Walsh transform.

38. The device according to p. 36, characterized in that it further comprises a multiplier which forms the product of the received signal and a special sequence, generating descrambling signal, while the primary decorrelator generates serial correlation descrambling received signal with the subsequence member of the set of all sequences of the Walsh-Hadamard transform.

39. The device according to p. 38, characterized in that the primary and secondary the project when determining the scrambling code group for the received signal in a digital communication system, in which the signals scribblenauts through respective scrambling codes, scrambling codes assigned to the corresponding scrambling code groups, identity groups, scrambling codes are encoded in the signals by means of respective code words, comprising a generator of special sequences, which generates a sequence with complex elements constant, multiplier forming the product of the received signal and a special sequence, generating descrambling received signal, the generator sequences are Walsh-Hadamard transform, generating at least one sequence of the Walsh-Hadamard transform, and decorrelator forming at least one correlation descrambling received signal, at least with one sequence of the Walsh-Hadamard transform, generated by the generator sequences are Walsh-Hadamard transform.

41. The device according to p. 40, characterized in that the generator of special sequences includes a storage device from which sampling is a special sequence.

42. The device according to p. 40, wherein the sequence generator is Hadamard.

43. The device according to p. 40, characterized in that the generator sequences are Walsh-Hadamard includes a storage device, from which a sample is selected at least one sequence of the Walsh-Hadamard transform.

44. The device according to p. 40, characterized in that the generator sequences are Walsh-Hadamard transform and decorrelator are processor fast Walsh transform.

 

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The invention relates to broadband communication systems based on spread spectrum via a direct pseudo-random sequence and can be used, in particular, in satellite communication systems or terrestrial communication systems with multiple access based on code division channels

The invention relates to electrical engineering and can be used in the communication system of channels (mdcr), in particular for the allocation of orthogonal codes in channels with variable data rate, and channel expansion according to the distribution

The invention relates to the field of radio and can be used in the mobile communication system mdcr for the formation of complex quasiorthogonal codes and to expand channel data using a set of complex codes quasiorthogonal

The invention relates to the field of radio and can be used in communication systems MDCRC, simultaneously using orthogonal codes quasiorthogonal

The invention relates to data transmission for communication systems, multiple access, code-division multiplexing (mdcr), in particular to a device and method of manufacture and distribution of characters, preventing deterioration of characteristics of the channel during data transmission

The invention relates to a receiving device and method for communication systems

The invention relates to a device and method of coding for mobile communications and more particularly to a device and method for producing the Quaternary complex quasiorthogonal codes and further use of these developed Quaternary complex quasiorthogonal codes to generate signals channel expansion

The invention relates to radio communications and can be used in space and terrestrial radio links with reuse frequency

The invention relates to telecommunication and can be used in wired, radio, microwave and satellite communication systems

The invention relates to communication technology, and in particular to a communication system in which a user transmits data variable speed

The invention relates to the field of electric and radio communication and can be used in wired, radio, radio-relay and meteoric lines

The invention relates to method and apparatus for data transmission in a system with multiple carrier frequencies

The invention relates to communication systems, spread spectrum, providing the opportunity for multiple transmitters to share a single channel multiplex transmission code division (MPCR) or channel multiple access code division (mdcr) by using these channels orthogonal transmitted signals

The invention relates to electro - and radio and can be used in wired, radio, microwave and satellite communication

The invention relates to radio communications and can be used in space and terrestrial radio links with reuse frequency

The invention relates to communication technology and can be used in synchronous or asynchronous address communication systems for sealing signals

The invention relates to a method, device and the telecommunications network to eliminate signal interference when conducting two-way communication with time division, when messages are transmitted in the first direction of communication in the first time segment and the second direction of the communication in the second time segment
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