Subscriber unit and method of its use in a wireless communication system
The invention discloses a method of signal encoding and device for its implementation, used in the subscriber unit of a wireless communication system. In the encoding of the signal with the variable speed transmission to generate a frame having a fixed number of characters. With this purpose, alternating with the original frame coded symbols to obtain a sequence perenesennyj characters, repeat the sequence perenesennyj characters several times, attaching a portion of the sequence perenesennyj characters. The number of iterations and the size of the parts of the sequence perenesennyj symbols based on the number of code symbols in the source frame code. 2 N. and 27 C.p. f-crystals, 14 tab., 7 table.
The technical field to which the invention relates.
The present invention relates to a subscriber unit and a method for use in a wireless communication system.
The level of technology
In wireless communication systems, including cellular and satellite communication systems, and systems dvuhpunktovoy (direct) communication using a wireless communication line on the basis of a modulated radio frequency (RF) signal the ranks, including due to the increased mobility and reduced infrastructure requirements compared to wired communication systems. One of the drawbacks of wireless communication line is its limited bandwidth due to the limited bandwidth available bandwidth radio frequencies (RF). On the contrary, in wired communication systems such limitation, because bandwidth can be increased by installing additional wired connections.
Subject to the restrictions inherent in the RF band, have been developed various methods of signal processing that improves the efficiency of use of a wireless communication system available RF bandwidth. A common example of such an effective signal processing in the frequency band is standard for the interface in the air IS-95 and its modifications, such as IS-95-A and ANSI J-STD-008 (as defined below under General reference as the standard IS-95), published by the Association of communications industry (TIA) and used mainly in cellular telecommunication systems. The standard IS-95 includes the use of methods of signal modulation, multiple access and code division multiplexing (mdcr) for simultaneous transmission of multiple messages in the same capacity allows to increase the total number of calls and other messages which can be transmitted in a wireless communication system, among other things due to repeated use of the frequency that is not present in other methods of wireless telecommunication. Using methods mdcr in the communication system with multiple access, disclosed in U.S. Patent No. 4901307 "SPREAD SPECTRUM COMMUNICATION SYSTEM USING SATELLITE OR TERRESTRIAL REPEATERS," and U.S. Patent No. 5103459 "SYSTEM AND METHOD FOR GENERATING SIGNAL WAVEFORMS IN A CDMA CELLULAR TELEPHONE SYSTEM", both patents incorporated here by reference and owned by the assignee of the present invention.
In Fig.1 shows a greatly simplified diagram of a cellular telephone system configuration, ensure the use of the standard IS-95. During operation, the set of subscriber points 10a-d performs wireless communication by establishing one or more RF interfaces with one or more ground stations 12a-d, using modulated RF signals with mdcr. Each RF interface between the base station 12 and the subscriber unit 10 includes a signal direct line of communication transmitted from the base station 12, and the signal return line communication transmitted from the subscriber unit. When using these interfaces communication with another user is usually performed using a switching center of a mobile phone SWE, SMC 14 and the PSTN 16 is generally carried out in the form of a wired connection, although it is also known the use cases for this purpose, additional RF or microwave communication lines.
According to the standard IS-95, each subscriber unit 10 transmits user data via the signal channel incoherent back of the line with a maximum data rate of 9.6 or 14.4 kbps, depending on the set speed, which is selected from a set speed settings. Non-coherent communication line is a line in which the receiving system does not use information about the phase. Coherent communication line is the line where the receiver is in the process uses the available information about the phase of the carrier. Information about the phase is usually obtained from a reference signal (pilot signal), however, to assess the value of the phase can be also based on the transmitted data. The standard IS-95 is also satisfied with the set of sixty-four Walsh codes, each of which contains sixty-four element (chip) for use in a direct line.
The use of single-channel signal incoherent return line communication according to the standard IS-95 maximum transmission rate of 9.6 or 14.4 kbps, well p is tirovannoj voice or digital data with a lower transmission rate, for example, the facsimile data. Non-coherent channel for line feedback was chosen because in a system where communication with the base station 12 for each allocated frequency bands 1,1288 MHz can make up to 80 subscriber units 10, while providing the necessary control data in the transmission from each subscriber unit 10, the set of subscriber units 10 significantly increase the level of mutual interference. Also, the data transmission speeds of 9.6 or 14.4 kbit/s ratio of the transmission power control data to the power transmission of user data is quite significant, which also increase the interference between subscriber units. The use of single-channel signal return line due to the fact that the execution of only one form of communication is consistent with wired phones and this concept is based modern wireless cellular communication. In addition, the signal processing in the presence of one channel is not as difficult as in the case of multiple channels.
With the advancement in technology of digital communication you should expect a substantial increase in requirements for wireless data transmission for such application areas as interactive the communication systems and operating conditions of the respective interfaces. In particular, data will be transmitted with a higher maximum speeds and in a wider range of possible speeds. You might also need a more reliable transmission, as errors when the data transmission is less tolerant than errors in the transmission of audio information. In addition, with the increased number of data types needed in the simultaneous transmission of data of many types. For example, in the process of maintaining audio or video interface, you may need to exchange data file. In addition, with the increased speed of transmission from the subscriber unit number performing communication with the base station 12 and subscriber units 10 per RF band of this width will decrease because the increase in the speed of data transmission will cause the same bandwidth, the base station can be achieved with a smaller number of subscriber units 10. Some of the layers may be the case that the currently used reverse link IS-95 will not be able to be adapted to such changes. Thus, the present invention relates to the creation of an interface with mdcr with higher data transfer speed and efficiency and the ü inventions
According to one aspect of the invention features subscriber unit or another transmitter for use in a wireless communication system, and the subscriber unit includes: a variety of information sources to issue an information data; an encoder for encoding the information data; a multitude of sources for data output control and a modulator for modulating the encoded information data and control data from one or more sources from a variety of sources in accordance with different modulation codes for transmission to the carrier, in which the modulator is designed so that it combines the encoded information data from one information source and the encoded data management, before they are output for transmission.
According to another aspect of the invention provides a base station or other receiver for use in a wireless communication system, and base station includes a receiver for receiving the carrier and discharge from her encoded data from multiple information sources, modulated corresponding to different modulation codes, and data management from the centre of the respective different modulation codes and encoded data from one information source are combined with the encoded control information; a demodulator for demodulating the encoded information data and control data on the basis of respective different modulation codes and decoder for encoding the encoded information and data management.
According to another aspect of the invention proposes a method for data management, master data and additional data from the first subscriber unit from a set of subscriber units to the base station associated with a set of subscriber units, comprising: (a) modulation of the additional data, the first Walsh code; (b) modulation of the main data by a second Walsh code, and (C) modulation data management third Walsh code, in which first Walsh code is shorter than the second Walsh code, and the second Walsh code is shorter than the third Walsh code.
According to further aspect of the invention proposes a method of data transmission from the subscriber unit for use in a wireless communication system, the method includes: receiving data from multiple data sources; coding of data; receiving management data from multiple sources, control and modulation encoded information data and control data from one or more sources UPRAVA, in which the encoded data from one information source is combined with the encoded data management before they are output for transmission.
According to one variant of the invention creates a set of user channels with individual gain control through the use of a set of complete subchannel orthogonal codes having a small number of PS widening of the elements of one period of the orthogonal signal. The data transmitted through one of the transmission channels, are subjected to low-speed coding with error correction, and then they before modulation is one of complete subchannel codes sequentially repeated, are subjected to the gain control and are summed with the data modulated using other kernel client codes. The resulting total data is modulated using a long code of the user and extending pseudorandom code (PS code) and converted with increasing frequency to perform the transfer. The use of short orthogonal codes provides noise reduction, while allowing to perform encoding with error correction and repetition for temporary explode to overcome the Rayleigh Zamir is a variant of the invention set complete subchannel codes consists of four Walsh codes, each of which is orthogonal to the rest of the set and has a duration corresponding to the four elements. It is preferable to use a small number (e.g. four) of the subchannel, as it allows the use of shorter orthogonal codes; although using a larger number of channels and, therefore, longer codes are also not inconsistent with the invention. In another embodiment of the invention, the length or number of elements in each channel code are different, to further reduce the ratio of the peak power to the average.
In a preferred illustrative embodiment of the invention the control data is transmitted over the first transmission channel, and control data power transmitted on the second transmission channel. The remaining two transmission channel used for transmitting General digital data, including user data, alarm data, or both. In the illustrative embodiment, the configuration of two General transmission channels adapted for modulation type DPFM (dip phase shift keying) and transmission quadrature channel.
Brief description of drawings
Signs objectives and advantages of the present SFL drawings, in which the same reference position identify corresponding elements in all the drawings and where:
Fig.1 is a block diagram of a cellular telephone system;
Fig.2 is a block diagram of the subscriber unit and the base station, the configuration of which corresponds illustrative variant of the invention;
Fig.3 is a block diagram of a channel encoder DPFM and channel encoder FMCS (phase shift keying with Quaternary signals), the configuration of which corresponds illustrative variant of the invention;
Fig.4 is a block diagram of a processing system of signal transmission, the configuration of which corresponds to the illustrative variant of the invention;
Fig.5 is a block diagram of a system for processing signal, the configuration of which corresponds to the illustrative variant of the invention;
Fig.6 is a block diagram of a system "finger" processing (finger processing), the configuration of which corresponds to one variant of the invention;
Fig.7 is a block diagram of the channel decoder DPFM and channel decoder FMCS, the configuration of which corresponds illustrative variant of the invention;
Fig.8 is a block diagram of a processing system of signal transmission, the configuration of which corresponds to the second illustrative variant of the invention;
Fig.9 is a block diagram with the K-system signal processing transmission the configuration of which corresponds to another variant of the invention;
Fig.11 is a block diagram of the encoding process is performed for the main channel, with a configuration corresponding to one variant of the invention;
Fig.12 is a block diagram of the encoding process is performed for the main channel, with a configuration corresponding to one variant of the invention;
Fig.13 is a block diagram of the encoding process performed for an additional channel, with a configuration corresponding to one variant of the invention;
Fig.14 is a block diagram of the encoding process is performed for the control channel, with a configuration corresponding to one variant of the invention.
Detailed description of preferred embodiments of the invention
A new and improved method and apparatus for high-speed wireless connection using mdcr described with reference to a part of the system cellular telecommunications relating to the transmission on the reverse link. Although the invention can be adapted for use when transmitting on the reverse of the communication line radial-node multipoint cellular communication system, the invention is equally applicable for transmission in a straight line. In addition, the present isovue wireless communication systems, dvuhpunktovoy wireless communication systems and systems that transmit radio frequency signals using coaxial or other broadband cables.
In Fig.2 shows a block diagram of the transmitting and receiving systems, made in the form of subscriber unit 100 and the base station 120. The first data set (data DPPM) is a channel encoder DPFM 103, which generates a stream of code symbols with a configuration adapted to perform DPFM, with the specified stream shall be taken by the modulator 104. The second data set (data FMCS) is a channel encoder FMCS 102, which generates a stream of code symbols with a configuration adapted to modulate FMCS, with the specified thread and was adopted by the modulator 104. The modulator 104 receives data management capacity and control data, which is modulated along with the encoded data DPFM and PMCS in accordance with the methods of multiple access, code-division multiplexing (mdcr), to generate a set of modulation symbols received by the processing system 106 RF. The processing system 106 RF filters and transforms with increasing frequency the set of modulation symbols in the frequency carrier for transmission to the base station 120 with ispolzovat link multiple subscriber units.
In the base station 120, the processing system RF 122 receives via the antenna 121 transmitted RF signals and performs bandpass filtering, transformation with decreasing frequency until the frequency band of the modulating signals and digitizing (digitization). The demodulator 124 receives the digitized signal and performs demodulation in accordance with the methods mdcr to retrieve data "soft solutions" DPFM and FMCS. Channel decoder DPFM 128 decodes data "soft solutions" DPFM received from the demodulator 124, getting the best data evaluation DPFM and channel decoder FMCS 126 decodes data "soft solutions" FMCS received from the demodulator 124, getting the best data evaluation FMCS. Then the best estimate of the first and second sets of data available for further processing or directions to the next destination, and the data for power control are used, either directly or after decoding to adjust the transmit power of the communication, which is used for data transmission terminal block 100.
In Fig.3 shows a block diagram of a channel encoder DPFM 103 and channel encoder FMCS 102, the configuration of which corresponds illustrative (control with cyclic redundant code) 130, which generates a checksum for each 20-millisecond frame of the first data set. The data frame along with the checksum of KICK is taken by the generator tail bits 132, which adds to the end of the tail bits, containing eight logical zeros at the end of each frame, to provide a known state at the end of each of the decoding process. Then the frame, including the tail bits and the checksum of KICK, accepted convolutional encoder 134, which performs convolutional coding with code length restrictions (K) 9 and the speed (R) 1/4, thereby generating coded symbols with a speed four times higher than the rate at the input of the encoder (ER). Alternatively, coding with other speeds, including speeds of 1/2, but using a rate 1/4 is more preferable because this produces the best balance of complexity and efficiency. Block interleaver 136 performs interleaving of bits per code symbol to provide a temporary separation for a more reliable transmission in fast fading. The resulting movement of characters accepted by the repeater with adjustable starting point 138, which povtorjai is molov with constant speed, which corresponds to the outgoing frames having a fixed number of characters. The repetition of a sequence of characters also increases the temporal separation of data needed to overcome fading. In the illustrative embodiment, a constant number of characters is 6144 for each frame, which gives the value of the symbol rate 307,2 of kilosymbols per second (KS/s). Repeater 138, from repetition, also uses different starting point for each sequence of characters. If the value of NRneeded to generate 6144 characters in the frame is not an integer, then the final repetition is performed for only a portion of the sequence of symbols. The resulting set of repeated symbols is taken Converter DPFM 139, which generates a stream of code symbols DPFM (DPPM) having values +1 and -1, to perform DPFM modulation. Alternatively, the follower 138 is placed over block interleaver 136, so that the block interleaver 136 receives the same number of characters for each frame.
In the channel encoder FMCS 102 data FMCS accepted by the checksum generator KICK 140, which generates a checksum for each 20-millisec is, the which adds a set of eight tail bits having a value of logical zero to the end of the frame. The frame, including now the code tail bits and a checksum for KICK, accepted convolutional encoder 144, which performs convolutional encoding with K=9, R=1/4, generating code symbols at a speed four times higher than the rate at the input of the encoder (ER). Block interleaver 146 performs interleaving bits in the code symbols and the resulting alternating characters are accepted by the repeater with variable power point 148. Repeater with adjustable starting point 148, using for each repetition a different starting point in the sequence of symbols interspersed repeats the sequence of characters sufficient number of times NRwhen generating 12288 symbols for each frame, which gives the value of the speed of transmission of the code characters 614,4 of kilosymbols per second (KS/s). If NRnot an integer, then the final repetition is performed for only a portion of the sequence of symbols. The resulting recurring characters are accepted Converter FMCS 149, which generates a stream of code symbols FMCS having a configuration that enables the execution of modulation FMCS, and provided is adosow) stream code FMCS with values +1 and -1 (FMCSQ). Alternatively, the follower 148 is placed over block interleaver 146, so that the block interleaver 146 receives the same number of characters for each frame.
In Fig.4 shows a block diagram of the modulator 104 of Fig.2 configuration corresponding illustrative variant of the invention. Each character DPFM of the channel encoder DPFM 103 is modulated by Walsh code W2using multiplier 150b, and each character FMCS1and FMCSQfrom the channel encoder FMCS 102 is modulated by Walsh code W3using multipliers 150C and 154d. These power control (MIND) is modulated by Walsh code W1using the multiplier 150A. The boost control 152 receives control data (COUNTER), which preferably have a logic level corresponding to the positive voltage, and adjusts the amplitude in accordance with the ratio of gain And0. The signal to the COUNTER shall not be user data, and provides the base station with information about the phase and amplitude so that the base station can coherently to demodulate data transmitted by the other subchannels, and to scale the output values "soft solutions" for their combination. The controller with many brand is availa able scientific C factor or gain of A1a gain control 156 adjusts the amplitude of the channel data DPFM, modulated by Walsh code W2in accordance with a variable gain And2. Gain a and 158b in accordance with the ratio of gain And3adjusts the amplitude of the characters FMCS in-phase and quadrature modulated respectively by the Walsh code W3. Four Walsh code used in the preferred embodiment of the invention, is shown in table I.
Specialists in the art it is obvious that the code W0absolutely not suitable for modulation and, as shown, corresponds to the processing of the control data. Control data modulated power code W1data DPFM code W2and the data FMCS code W3. After modulation by the appropriate Walsh code control data, control data power and data DPFM transmitted in accordance with the methods DPFM and data FMCS (FMCSIand FMCSQ- in accordance with the methods FMCS, as described below. It should also be borne in mind that there is no need to use each orthogonal code, and in an alternative embodiment of the invention, where the user provides only about what Buet generate fewer items on one character and consequently, enables a broader coding and repetition compared to systems that use longer Walsh codes. This broader coding and repetition provides protection against Rayleigh fading, which is the main source of errors in terrestrial communication systems. Use a different number of codes and code lengths is consistent with the present invention, however, a set of larger number of Walsh codes with greater length reduces the effectiveness of protection from fading. Using a four-element code is optimal, since the four channels provide significant flexibility in the transfer of different data types, as shown below, while maintaining the short length of the code.
The adder 160 adds the resulting modulation symbols with the adjusted amplitude coming from the gain 152, 154, 156 and a, generating a total modulation symbols 161. PS extends codes PSIand PSQexpanded by multiplying by a long code 180 using multipliers a and 162b. The resulting pseudo-random codes provided by multipliers a and 162b are used to modulate the total characters module using multipliers 164a-d and adders 166a and 166b. Then the resulting component in the phase of XIand the quadrature component of XQfiltered (filter not shown) and converted with increasing frequency to the carrier frequency in the processing system 106 RF, shown in highly simplified form, using multipliers 168 and two sine waves in phase shifted by 90 degrees. Alternatively, the invention can also be used transformation FMCS with increasing frequency and shift. The resulting signals with high frequency in-phase and quadrature are added using adder 170 and amplified by the main amplifier 172 in accordance with the main adjustment ratio AMto generate the signal s(t), which is transmitted to the base station 120. In a preferred embodiment of the invention the signal is expanded and filtered in the band 1,2288 MHz, to preserve compatibility with the bandwidth of existing channels mdcr.
Providing multiple orthogonal channels through which data can be supplied, as well as using repeaters with adjustable frequency, which reduces the number of iterations NRperformed in accordance with the high speed data input, the above-described method and system obrabotannye speeds. In particular, reducing the frequency of repetitions NRperformed by the repeater with adjustable starting point 138 or 148 in Fig.3, it is possible to maintain a higher speed ERat the encoder input. In an alternative embodiment of the invention convolutional coding with rate 1/2 runs at twice the repetition rate of NR. Set speed encoder ERsupported by the repetition frequency NRand the speed of encoding R, equal to 1/4 and 1/2 for channel DPFM and channel FMCS shown in tables II and III, respectively.
In tables II and III it is shown that by selecting the number of repetitions of sequences of NRyou can support a variety of data transmission speeds including high-speed data transmission, when the speed at the input of the encoder ERcorresponds to the data rate minus the constant, necessary to transfer QUICK code tail bits, and any other additional service information. From tables II and III also shows that FMCS modulation can be used to increase the speed of data transmission. Commonly used speed supplied labels, for example 64 and High speed - 32, have speed traffic 72, 64 and 32 kbit/s, respectively, and for signaling and other data management they are multiplexed, respectively, with speeds of 3.6, and 5.2 and 5.2 kbit/s Speed RS1 - Full speed and RS2 - Full speed correspond to the speeds used in communication systems operating according to the standard IS-95, which is also very useful from the point of view of compatibility. Zero speed corresponds to the transmission of one bit and is used to indicate the destruction of the frame, which is also part of the standard IS-95.
The data rate can also be increased by simultaneous transmission of data from two or more channels of the multiple orthogonal channels, either in addition or instead of increasing the transmission rate by reducing the repetition frequency NR. For example, a multiplexer (not shown) can divide a single data source to multiple sources of data that are transmitted across multiple subchannels of data. Then the total transmission rate can be increased either by transmitting on a particular channel at a higher speed, or by performing multiple transfers simultaneously on multiple channels, or both, until you have exceeded the bandwidth sposobstovat the maximum transmit power of the transmitter system.
The provision of multiple channels increases the flexibility when transmitting data of different types. For example, the channel DPPM can be used for voice data, and the channel PMCS for digital data transmission. This can be generalized further by allocating one channel for data transmission, time-dependent, for example speech, characterized by a lower baud rate, and selection of another channel for data transmission, less time-dependent, for example digital files. In this embodiment, the interleaving can be performed over large blocks of data, less time-dependent, so as to further increase the temporal diversity. In another embodiment of the invention the channel DPFM does the bulk of the data transmission and channel FMCS is sending the overflow. The use of orthogonal Walsh codes eliminates or significantly reduces mutual interference in the set of channels, which is a transmission from the subscriber unit, resulting in minimized energy transfer required for successful reception of these channels at the base station.
To increase throughput when processing signals in the receiving system and, consequently, the extent of use of high power parentrole data the receiver system can perform coherent processing by identifying and eliminating the phase shift of the feedback signal line. Control data can also be used for optimal weighting of the multibeam signals received with different time delays before they will be combined in a Rake-receiver. After elimination of the phase shift and the corresponding weighting multipath signals can be combined, reducing power, which should be the signal return line connection for appropriate processing. This reduction of the required power reception can successfully handle the transfer with higher speeds or, conversely, to reduce mutual interference in the set of signals a return line connection. Although transmission of the control signal required some additional transmit power, but with a higher transmission speed ratio of the power control channel to the total signal power return line is significantly lower than the same ratio in a low-speed cellular systems for transmitting digital voice data. Thus, in high speed data transmission system with mdcr winning against Eb/N0customnet, necessary for the transmission of control data from each subscriber unit.
The use of gain 152-158, as well as the main amplifier 172 additionally increases the utilization of high power transmission of the above-described system due to the fact that the transmission system has the ability to adapt to different parameters of radio channels, data rates and data types. In particular, the transmit power of the channel required for reliable reception may vary over time and under changing conditions so that it is not dependent on the other orthogonal channels. For example, during the initial capture of the signal return line connection may require increasing the capacity of the control channel in order to facilitate the detection and synchronization at the base station. However, as soon as the signal return line connection is accepted, the required transmit power control channel is significantly reduced and will vary depending on various factors, including the speed of movement of the subscriber units. Accordingly, the coefficient value of the gain control And0will increase in the capture of the signal, and then decreased during the current connection. In kogorou is transferred in a straight line, not prone to sinking, the ratio of the gain of A1can be reduced, as the requirement of data transmission power control with low frequency of occurrence of errors is not so hard. Whenever there is no need to regulate the power factor of the gain of A1it is preferable to reduce to zero.
In another embodiment of the invention additionally uses the opportunity to gain control of each orthogonal channel signal or the entire back line, by providing the base station 120 or other receiving system to modify the gain control channel signal or the entire back line, using commands to control power transmitted by a signal in a straight line. In particular, the base station may transmit the control information of the power that sets the transmission power of the specific channel or signal the entire back line to be adjusted. In many cases, this approach has advantages, including cases where the channels DPFM and FMCS transferred two types of data having different sensitivity to errors, for example, digitized voice data and digital data. In this case the RC. If the actual frequency of occurrence of errors in the channel exceeds a specified, then the base station will command the subscriber unit to decrease the gain of this channel up until the actual frequency of occurrence of errors reaches a given. In the end, this will lead to the fact that the ratio of the gain of one channel will increase relative to another channel. That is, the ratio of the gain associated with data that is more sensitive to errors, will increase relative to the ratio of the gain associated with less sensitive data. In other cases, it may be necessary to adjust the transmit power of the entire back line due to fading or moving subscriber unit 100. In such cases, the base station 120 may perform power control by sending a single command power control.
Thus, due to the possibility of independent gain control of the four orthogonal channels, as well as related control channels total transmit power of the reverse communication line can be maintained at the minimum level required for successful transmission of each data type, whether the control data is of the transmission may be defined differently for each type of data. Transfer with minimum necessary power level allows you to transmit to the base station maximum (based on the target values possible transmit power of the subscriber unit) amount of data, and reduces mutual interference between subscriber units. This decrease mutual interference increases the overall throughput of the wireless cellular system mdcr in General.
Channel power control used in the signal return line allows the subscriber unit to transmit to the base station, the control information of the transmission power at different speeds, including the rate of 300 bits power control in the second. In a preferred embodiment of the invention bits power control instructs the base station to increase or decrease the transmit power of the channel traffic direct line of communication used to transmit information to the subscriber unit. Although the system mdcr fast power control is useful in all cases, it is particularly effectively applied to high-speed communications, including transmission of data, since the digital data is more sensitive to errors, and transfer with high speed leads to the fact that a significant amount of data terae the Institute of communication accompanied by a high-speed transmission in a straight line, the provision of high-speed signal transmission power control on the reverse line of communication is further facilitated by the implementation of high-speed communication in wireless telecommunication systems with mdcr.
In an alternative illustrative embodiment of the invention for transmitting a particular type of data, a set of velocities at the input of the encoder ERdetermined by a specific value of NR. That is, data can be transmitted with the maximum velocity at the inlet of the encoder ERor set a lower speed at the input of the encoder ERif configured values of NR. In a preferred implementation of the present invention, the maximum speed corresponds to the maximum speed used in the wireless communication system compliant with the standard IS-95 (see above tables II and III), namely: RS1 - Full speed and RS2 - Full speed; each lower speed is about half of the next higher speed, which creates a set of velocities, which includes full speed, half speed, speed "one quarter" and speed "one-eighth". Lower data rate is preferably generated by increasing h the PFM, presented in table IV.
The rate of recurrence for channel FMCS two times higher than for channel DPFM.
In accordance with an illustrative variant of the invention, where the data rate of the frame is changed in accordance with the previous frame, the transmit power of the frame is adjustable in accordance with a speed change transmission. That is, if after the frame is transmitted at a higher speed, is transmitted to the frame with a lower rate, the transmit power of the channel, which is transmitted to the frame, lower frame with a lower transmission rate in proportion to the decrease in speed and Vice versa. For example, if the transmit power of the channel during transmission of the frame with full speed represents the value of T, the transmit power during the next transmission frame at half speed will be T/2. Reducing the transmission power, it is preferable to perform by reducing the transmission power over the entire frame, but this can also be done by reduction of the working cycle, so that some redundant information "was passed". In any case, adjusting the transmission power is performed in combination with the mechanism of a closed control newnownext, transmitted from the base station.
In Fig.5 presents a block diagram of a processing system RF demodulator 122 and 124 in Fig.2 configuration corresponding illustrative variant of the invention. Multipliers 180 and 180b lower frequency signals received from the antenna 121 using a sine wave in-phase and quadrature sinusoids, creating a reception sampling in the phase of RIand quadrature reception sampling RQrespectively. It should be borne in mind that the processing system RF 122 shown in highly simplified form, and that these signals are also filtered and converted to digital form (not shown) in accordance with known methods. Then foster sampling RIand RQserved on the finger demodulators (finger demodulator) 182 in the demodulator 124. Each finger demodulator 182 processes the instance of the signal return line passed to the subscriber unit 100, when such an instance is available, where each instance of the signal return line is generated in the result of the phenomenon of multipath propagation. Although here shown three finger demodulator, the invention allows the use of alternative number of finger processors, including the use of one finger demodulator 182. the d, data DPFM and data FMCSIand FMCSQ. Each dataset "soft solutions" is also a temporary setup in the corresponding finger of the demodulator 182, although in an alternative embodiment of the invention, the temporary setting can be performed in the multiplexer 184. Then the combiner 184 summarizes the datasets "soft solutions" obtained from the finger demodulator 182 to produce a single instance of the data output control DPFM, FMCSIand FMCSQ.
In Fig.6 presents a block diagram of the digital demodulator 182 in Fig.5 configuration corresponding illustrative variant of the invention. Foster sampling RIand RQthe first time regulated using a temporary settings 190 in accordance with the magnitude of the delay introduced by the transmission path of the specific instance of the processed signal return line. Long code 200 is mixed with extending pseudorandom codes PSIand PSQusing multipliers 201, and a complex conjugate value of the resulting long code modulated extends codes PSIand PSQcomprehensive multiplied by the configured time foster sampling RIand RQwith use and a separate instance of the components of XIand XQdemodulated using Walsh codes W1, W2and W3respectively, and the resulting demodulated using Walsh codes data are summarized according to the four elements demodulation using adders 4:1 212. The fourth instance of the data XIand XQsummed across the four elements demodulation using adders 208 and is then filtered using the filter control signals 214. In a preferred embodiment of the invention, the filter control signal 214 performs averaging on a number of the summing performed by the adders 208, but the experts in this field of technology is obvious and other filtering methods. The filtered control signal in-phase and quadrature control signal is used to phase shift and scaling of the data demodulated Walsh codes W1and W2in accordance with the data modulated DPFM through multiplication by the complex conjugate value of using multipliers adders 216 and 217, resulting in data "soft solutions" power control and DPPM. The data modulated by Walsh code W3shifted in phase by using the filtered control the oil 218 and adders 220, resulting data "soft solutions" FMCS. Data "soft solutions" power control are summarized in 384 modulation symbols by using the adder 384:1 222, resulting in data "soft solutions" power control. Then dephased modulated by Walsh code W2the data modulated by Walsh code W3data and "soft solutions" power control become available to join. In an alternative embodiment of the invention with the data management capacity is also the encoding and decoding.
In addition to providing information about the phase control signal can also be used in the receiving system to facilitate temporary tracking. Temporary tracking is performed during processing of the current receiving sample and by processing the received data at the beginning and at the end of the sample. To determine the point in time that best fits with a valid receipt, the amplitude of the control channel at the beginning and end of the sample can be compared with the amplitude of the sample at the moment to determine the greatest of them. If the signal is in one of these neighboring points more than signay demodulation.
In Fig.7 presents a block diagram of the channel decoder DPFM 128 and channel decoder FMCS 126 (Fig.2), the configuration of which correspond illustrative variant of the invention. Data "soft solutions" DPVM from the combiner 184 (Fig.5) are accepted by the memory 240, which stores the first sequence of 6144/NRsymbol demodulation in the receiving frame, where NRdepends on the speed of data transfer "soft solutions" DPFM, as described above, and adds each successive set of 6144/NRdemodulated symbols contained in the frame, corresponding to the accumulated symbols. Reverse block interleaver 242 performs a reverse alternation of accumulated data "soft solutions" coming from the adder with variable starting point 240, and the Viterbi decoder 244 decodes data "soft solutions", subjected to reverse alternation, to receive data "tough decisions" (hard decision data), and the resulting checksum values KICK. The decoder FMCS 126 data "soft solutions" FMCSIand FMCSQfrom the combiner 184 (Fig.5) demultiplexers into a single data stream of soft decisions using a demultiplexer 246, and a single data stream "soft decisions" taken by the NAC the Chi data FMCS. Reverse block interleaver 250 performs a reverse interleaving data "soft solutions" coming from the adder with variable starting point 248, and the Viterbi decoder 252 decodes the modulation symbols subjected to reverse alternation, to receive data "tough decisions", and the results of the checksum KICK. In an alternative illustrative embodiment described above with reference to Fig.3, in which the repetition of symbols is performed before alternation, drives 240 and 248 are back after a block of premaritally 242 and 250. In a variant of the invention, which uses sets of velocities, and hence in which the speed of the particular frame is not known, use a lot of decoders, each of which operates with a different baud rate, and then based on the results of checksums KICK selected frame associated with the most likely of the used transmission speeds. In the practical use of the present invention is allowed to use other methods of error control.
In Fig.8 presents a block diagram of the modulator 104 (Fig.2), the configuration of which corresponds to an alternative variant of the invention, when using single channel data DPFM. Regulation is Cai gain And0These power control is modeled by a multiplier 150A using Walsh code W1a gain control 454 performs gain control in accordance with the ratio of the gain of A1. Control data after gain control and data management capacity are summed in adder 460, resulting in receive summary data 461. Data DPFM modulated by the multiplier 150b using Walsh code W2, then a gain control 456 adjusts the gain according to the ratio of the gain And2.
Pseudo-random code extends in phase (PSI) and quadrature pseudorandom code extends (PSQ) modulated long code 480. The resulting modulated long ID codes PSIand PSQcomplex multiplied by the total data 461 and data DPFM with the adjusted gain coming from the boost control 456, using multipliers 464a-464d and adders a-466b, resulting in receiving the components of XIand XQ. Then the components of XIand XQconverted with increasing frequency by using multipliers 468, using a sine wave in phase and the sine wave is shifted by 90 degrees, and the result is accordance with the amplitude coefficient AMin the result, generates a signal s(t).
Variant shown in Fig.8, differs from the other options described here so that the data DPFM are in quadrature channel, while the control data and power control are in the channel signal in phase. Described in the previous embodiments of the invention data DPFM are along with the control data and power control channel signal in phase. Placing data DPPM in the quadrature channel, and control data and power control channel signal in phase reduces the peak-to-average signal power of the reverse link, and the orthogonality of the phases of the channels leads to the fact that the sum of the two signal channels changes less in response to changes in the data. This reduces the peak power required to maintain a given average power and thus reduces the ratio of peak power to average power for the signal return line. This reduction of peak power to average reduces the peak power, which should be the signal return line connection at the base station, in order to maintain a given transmit power, and sledovateljam to be located from the base station, before he becomes unable to transmit a signal that can be received at the base station with the required peak power. This increases the distance at which the subscriber unit can successfully communicate with a given data rate, or alternatively, to support higher data rate at a given distance.
In Fig.9 presents a block diagram of the digital demodulator 182 configuration, the corresponding variant of the invention shown in Fig.8. Foster sampling RIand RQconfigured time unit time settings 290, and codes PSIand PSQmultiplied by the long code 200 using multipliers 301. Past temporary setup foster sampling then multiplied by complex conjugate values of the codes PSIand PSQusing multipliers adders 302 and 304, resulting in receiving the components of XIand XQ. The first and the second instance of the components of XIand XQdemodulated multipliers 31.0 using Walsh code W1and Walsh code W2and the resulting demodulation symbols are added in sets of four characters using adders 312. Third eczema is a control reference data. Control reference data are filtered by filters control signals 314 and used to phase shift and scale the modulated data, summarized with Walsh codes using multipliers 316 and adders 320, resulting in data "soft solutions" DPFM, and after summation on the 384 characters in the adder 384:1 322 retrieves the data "soft solutions" power control.
In Fig.10 presents a block diagram of a transmission system with a configuration corresponding to one variant of the invention. The power gain of the channel 400 adjusts the gain control channel 402 on the basis of variable gain And0. Main channel symbols 404 is converted into a value of +1 and -1 Converter 405, and each symbol is modulated by Walsh code WFequal to +, +, -, - (where + = +1 and - = -1). The data modulated WFsubjected to the gain control based on the variable gain of A1gain control 406. The outputs of the gain 400 and 406 are added by the adder 408, resulting in data in phase 410. Additional channel symbols 411 is converted into the values + and - Converter 412, and each symbol is modulated by Walsh code WSequal to +, -. The boost control + and - inverter 416. Each symbol is modulated by Walsh code WCequal+, +, +, +, -, -, -, -. Symbols modulated WCbe subjected to the gain control gain control 418 based on the variable gain And3and output gain controls 414 and 418 are summed in adder 419 for receiving data 420 with the phase shifted by 90 degrees.
It should be borne in mind that, as Walsh codes WFand WShave different lengths and are generated with the same speed transmission elements, the main channel transmits the data symbols with the speed component of half the rate of the additional channel. For similar reasons, it should be borne in mind that the control channel transmits the data symbols at half speed relative to the speed of the main channel.
Data in phase 10 and quadrature data 420 are subject to complex multiplication by expanding codes PSIand PSQas shown in the figure, resulting in a component in phase XIand the quadrature component of XQ. Quadrature component of XQhas a delay of 1/2 of the length of the element PS extend the code to perform the expansion FMCS shift, and then component XIand component of XQPisa.
By using Walsh codes WF, WSand WCthat, as stated above, have different lengths, in this alternative provides a set of communication channels having a greater number of different speeds. In addition, the use of a shorter, two-element Walsh code WSfor additional channel provides additional orthogonal channel with a higher data rate when the ratio of the peak power to average power transfer, less than when using two channels on the basis of the 4-cell Walsh codes. This further improves the performance of the transmission system in the sense that this amplifier can support higher speeds or transfer at a greater distance, using a signal with a lower ratio of the peak power to average power transfer.
The pattern codes of the Walsh described with reference to Fig.10, can be considered as the distribution vosmiseriynogo interval Walsh in accordance with table VI.
In addition to the decrease of the ratio of peak power to average power transfer distribution sets canalobre, modulation using four Walsh codes of the eight elements and the summation of the results will require to have additional schemes, and therefore complicate the system.
In addition, it is seen that the transmission system shown in Fig.10, can work with a range of expansion and, therefore, with Walsh codes and extends codes generated with other speed different from the 1,2288 of makeelement/second. In particular, the bandwidth expansion 3,6864 MHz with a corresponding rate Walsh code and extension 3,6864 of makeelement/second. In figures 11-14 shows the encoding process performed for the primary channel, secondary channel and the control channel with the use of the band expansion 3,6864 MHz. Usually to configure the encoding process with the use of the band expansion 1,2288 MHz reduce the number of repetitions of characters. This principle, that is, adjustment of the number of repetitions of characters that can be applied more widely, increasing the bandwidth expansion, including, for example, the use of the band expansion 5 MHz. In the description below, figures 11-14, in particular, contain settings that are performed if coding system with a bandwidth extension 1,2288 MHz.
In Fig.11 shows the code the eighth), which form a set of speeds 1 standard IS-95, in accordance with one variant of the invention. Data comes in frames with a duration of 20 MS with the number of bits shown for each speed, and the control bits KICK and eight tail bits are added generators checksums KICK 500a-500d and generators tail bits 502a-502d. Additionally, for each speed convolutional encoders 504a-504d is convolutional coding with rate 1/4, generating four code symbols for each data bit, the bit KICK or tail bits. The resulting frame of coded symbols is subjected to a block interleaving using a block of premaritally 506a-506d, generating a specified number of characters. For the three lower speeds symbols are transmitted with a repetition using repeaters, transmission a-508, as shown in the figure, causing the generation of 768 code symbols for each frame. Then 768 code symbols for each frame is repeated 24 times repeaters characters 510A model-510d, generating 18432 code symbols per frame for each speed.
As discussed above, each code symbol in the main channel is modulated four-digit code Walsh WFgenerated with scorecount) the number of code elements Walma and expansion is 73628, which corresponds to the 4 elements Walsh for each of 18432 code symbols in the frame.
For a system operating with speed 1,2288 of makeelement/second, the number of repetitions of characters performed by repeaters characters 510A model-510d is reduced to eight (8). In addition, the repeater transmission 508b repeats the sequence of characters in the frame three (3) times, plus 120 characters transmitted for the fourth time, and the repeater transmitting 508 repeats the sequence of characters in the frame six (6) times plus 48 characters are repeated for the seventh time. In addition there is a fourth repeater transmission (or the fourth step of repeating the transmission) for better speed (not shown), which passes 384 symbol from the sequence of characters contained in the frame, a second time. These retransmission provide along 768 characters of the data that is being repeated by the repeater characters 510A model-510d eight times correspond 6144 characters that represents the number of elements in a frame duration of 20 MS at a speed of 1,2288 of makeelement/second.
In Fig.12 shows the coding performed for the four velocities, which form the set speed 2 of the standard IS-95, in accordance with one variant of the invention. Data comes in frames long the Oia backup bit a-521d for each speed. Also generators checksums KICK 520a-520d and generators tail bits 522a-522d added control bits KICK and eight tail bits. Additionally, for each speed convolutional encoders 524a-524d is convolutional coding with rate 1/4, generating four code symbols for each data bit, the bit KICK or tail bits. The resulting frame of coded symbols is subjected to a block interleaving using a block of premaritally 526a-526d, generating a specified number of characters. For the three lower speeds symbols are transmitted with a repetition using repeaters, transmission a-s, as shown in the figure, causing the generation of 768 code symbols for each frame. Then 768 code symbols for each frame is repeated 24 times repeaters characters 530a-530d, generating 18432 code symbols per frame for each speed.
For a system operating with a bandwidth extension 1,2288 of makeelement/second, the number of repetitions of characters performed by repeaters characters 530a-530d, reduced to four (4). In addition, the repeater transmission a transmits a sequence of symbols in the frame two (2) times, plus 384 symbol is transmitted for the third time. The repeater transmission 528b poweedge s repeats the sequence of characters in the frame ten (10) times, plus 96 symbols are repeated eleven times. In addition there is a fourth repeater transmission (or the fourth step of repeating the transmission) to full speed (not shown), which passes 384 symbol from the sequence of characters contained in the frame, a second time. These retransmission provide together 1536 symbols of the data that is being repeated by the repeater characters 530a-530d four times correspond 6144 characters.
In Fig.13 shows the encoding process for an additional channel, performed according to one variant of the invention. Data frames received at any speed out of eleven of these velocities, and the checksum generator 540 adds the 16-bit data checksum KICK. Generator tail bits 542 adds eight tail bits data encoder, resulting in frames having a specified data rate. Convolutional encoder 544 performs encoding with the code length limit K=9 and rate 1/4, generating four code symbols for each received data item bits KICK and tail bits, and a block interleaver 546 performs block interleaving on each frame and outputs for each frame a specified number of characters according to the size of the frame on the entrance.
Also shown is the coding for additional twelfth speed, which is performed in the same manner as for these eleven speeds, except that instead of encoding speed is 1/4 coding with rate 1/2. In addition, the repetition of characters is not performed.
In table VII presents the list of frame sizes, velocities at the input of the encoder speed codes and factors of repetition symbols N for different speeds of the following elements, which can be used in Fig.13 for selecting different speeds repetition of elements (corresponding to the band extension).
In Fig.14 shows a block diagram of the processing performed for the control channel for the system with a bandwidth extension 3,6864 MHz. Processing control bit, essentially, the same processing is performed for the other channels, except that there is additionally provided by the multiplexer 560 and the repeater characters 562, which is injected into a stream of code symbols unencoded bits power control. Bits of power control are generated with a frequency of 16 bits per frame and repeated 18 times the repeater characters 562, resulting in a 288-bit power control on kathmnadu one encoded symbol data", in the resulting generated 384 symbols per frame. Repeater characters 564 repeats 384 bits 24 times, generating 9216 symbols per frame for effective data transfer rate 500 kbit/s for data management and 800 kbps bits for power control. In a preferred embodiment, the processing performed for a system with a bandwidth of 1,2288 MHz, the number of performed repetitions of characters just reduced from 24 to 8.
Thus, there has been described a high-speed wireless communication system with mdcr. This description allows specialists in the art to make or use the present invention. Experts will easily be able to propose various modifications of the proposed options, and here formulated the fundamental principles can be applied to other variants, which are not required to have inventive ability. Thus understood that the present invention is not limited to the presented here options, and corresponds to the widest extent consistent with the disclosed here, the principles and new features.
Formula ispy: perform interleaving frame coded symbols to obtain a sequence perenesennyj characters and output frame having a constant number of symbols through repetition sequence perenesennyj characters several times and annexation of parts of the sequence perenesennyj characters.
2. The method according to p. 1, in which the number of repetitions based on the number of code symbols in the frame code.
3. The method according to p. 1, in which part of the sequence perenesennyj symbols based on the number of code symbols in the frame code.
4. The method according to p. 2, in which part of the sequence perenesennyj symbols based on the number of code symbols in the frame code.
5. The method according to any one of the preceding paragraphs, in which the sequence perenesennyj characters contains 216 characters.
6. The method according to any one of paragraphs.1-4, in which the sequence perenesennyj characters contains 120 characters.
7. The method according to one of paragraphs.1-4, in which part of the sequence perenesennyj characters contains 120 characters.
8. The method according to p. 5, in which part of the sequence perenesennyj characters contains 120 characters.
9. The method according to any one of paragraphs.1-4, in which part of the sequence perenesennyj characters contains 48 characters.
10. The method according to the Ohm number of repetitions is three.
12. The method according to p. 8, in which the number of repetitions is three.
13. The method according to p. 9, in which the number of repetitions is equal to six.
14. The method according to p. 10, in which the number of repetitions is equal to six.
15. Device for encoding a signal with a variable speed transmission for transmission containing interleaver made with the possibility to perform interleaving frame coded symbols to obtain a sequence perenesennyj characters, repeater, made with the possibility to give the frame with a constant number of characters through repetition sequence perenesennyj characters several times and by joining parts of the sequence perenesennyj characters.
16. A device for encoding a signal according to p. 15, in which the number of repetitions based on the number of code symbols in the frame code.
17. A device for encoding a signal according to p. 15, in which part of the sequence perenesennyj symbols based on the number of code symbols in the frame code.
18. A device for encoding a signal according to p. 16, in which part of the sequence perenesennyj symbols based on the number of code symbols in the frame code.
20. A device for encoding a signal according to any one of paragraphs.15-18, in which the sequence perenesennyj characters contains 120 characters.
21. A device for encoding a signal according to any one of paragraphs.15-18, in which part of the sequence perenesennyj characters contains 120 characters.
22. A device for encoding a signal according to p. 19, in which part of the sequence perenesennyj characters contains 120 characters.
23. Device for encoding a signal from one PP.15-18, in which part of the sequence perenesennyj characters contains 48 characters.
24. A device for encoding a signal according to p. 20, in which part of the sequence perenesennyj characters contains 48 characters.
25. A device for encoding a signal according to p. 21, in which the number of repetitions is three.
26. A device for encoding a signal according to p. 22, in which the number of repetitions is three.
27. A device for encoding a signal by p. 23, in which the number of repetitions is equal to six.
28. A device for encoding a signal according to p. 24, in which the number of repetitions is equal to six.
29. Device for encoding a signal with a variable speed transmission for transmitting containing means interleave frame Radovan number of characters through repetition sequence perenesennyj characters several times and by joining parts of the sequence perenesennyj characters.
FIELD: coding in communication systems.
SUBSTANCE: proposed partial reverse bit-order interleaver (P-RBO) functions to sequentially column-by-column configure input data stream of size N in matrix that has 2m lines and (J - 1) columns, as well as R lines in J column, to interleave configured data, and to read out interleaved data from lines.
EFFECT: optimized interleaving parameters complying with interleaver size.
4 cl, 7 dwg, 3 tbl