Method and device for data transmission in a system with multiple carrier frequencies

 

The invention relates to method and apparatus for data transmission in a system with multiple carrier frequencies. The technical result consists in maximilianii system throughput and increase diversity signal by dynamic multiplexing of signals on multiple carrier frequencies in a communication system with signal transmission in a wide range. To do this, perform data coding and separating the received coded symbols for transmission on different frequencies. The transmitter comprises a control processor to determine the bandwidth of each of the multiple channels and selecting a data rate for each channel depending on the specific bandwidth. Many subsystems of the transmission are controlled by signals from the control processor. Each transfer subsystem associated with the respective channel of the multiple channels for encoding the encoded data codes that are unique to the channel for transmission in the channel. Variable demultiplexer under control of the control processor further demultiplexes the coded data into many subsystems speeds, demuxing, obtained from the data rate selected for the I symbol, which stores a fixed transmission rate of the data symbols that must be transmitted. In another embodiment of the repetition of characters is not performed and sequences are used Walsh different lengths to handle changes in the speed of data transmission. 3 S. and 12 C.p. f-crystals, 4 Il., table 2.

I. Field of the invention the Present invention relates to a method and apparatus for data transmission in a system with multiple carrier frequencies. The present invention can be used to maximize system throughput and increase diversity signal by dynamic multiplexing of signals on multiple carrier frequencies in a communication system with signal transmission in a wide range.

II. Description of related technology, it is Desirable to be able to transfer data at speeds that are higher than the maximum data rate of a single CDMA channel. Conventional CDMA channel (as set the standard for cellular communications in the United States) are capable of transmitting digital data at the maximum transmission speed of 9.6 kbit/s using 64-bit extension function Walsh on 1,2288 MHz.

It was proposed many solutions to this problem. One solution is to control the parallel on multiple channels, available to them. Two ways to provide multiple CDMA channels for use by one user described in the concurrently pending application for United States patent serial number 08/431.180, entitled "Method and apparatus for providing variable rate data in a communications system using statistical multiplexing", registered on April 28, 1997, and the patent application U.S. serial number 08/838.240, entitled "Method and apparatus for providing variable rate data in a communications system using non-orthogonal channels overflow", registered on April 16, 1997, both of which transferred to the assignee of the present invention and is incorporated here by reference. Additionally, you may receive a passing frequency by transmitting data on multiple channels with a wide range, which are separated from each other in frequency. A method and apparatus for redundant data on multiple CDMA channels is described in U.S. patent number 5.166.951, entitled "Channel with a wide range of high bandwidth", which is included here by reference.

The technique of modulation multiple access code division multiple access (CDMA) users. In the technique known other technologies of communication systems, multiple access, such as multiple access with time division multiplexing (TDMA), multiple access frequency division multiple access (FDMA) modulation schemes AM (amplitude modulation), such as expansion/contraction amplitude with a single sideband (ACSSB). However, the modulation technique CDMA transmission signal in the expanded spectrum has significant advantages over these other technologies modulation for communication systems, multiple access.

The use of CDMA technology in the communication system, multiple access is described in U.S. patent number 4.901.307, entitled "communication System multiple access with signal transmission in a wide range using satellite or terrestrial repeaters", transferred to the assignee of the present invention and is incorporated here by reference. The use of CDMA technology in the communication system, multiple access is additionally described in U.S. patent number 5.103.459, entitled "System and method for generating waveforms of signals in the system of cellular CDMA", submitted to the assignee of the present invention and is incorporated here by reference. Communication systems, multiple access with catalanotti communications IS-95, entitled "Standard compatibility stations on the basis of the mobile stations for dual-mode wideband cellular systems with signal transmission in a wide range", which is included here by reference.

The shape of the CDMA signal, which by its inherent nature of the broadband signal, offers some form of frequency diversity by spreading the signal energy over a wide band of frequencies. Therefore, selective frequency fading (fading) affects only a small portion of the bandwidth of the CDMA signal. Space diversity or diversity in the paths of transmission on the forward/reverse channel is obtained by providing multiple signal paths through the simultaneously transmitted channels to the mobile user or from it through two or more antennas, cell sectors or cell sites. Moreover, the diversity paths can be obtained by using multi-channel environment by processing a wide range, allowing to separately receive and process signals with different propagation delays. Examples of usage explode the transmission paths shown in simultaneously considering the U.S. patent number 5.101.501, entitled "Soft relay transmission in the phone system CDMA", both of which are transferred to the assignee of the present invention and is incorporated here by reference.

Fig. 1 illustrates a transmission scheme for a system of multiple access code division multiple access (CDMA) with multiple carrier frequencies, in which each carrier frequency passes a fixed portion of the transmitted data. Frames bits of information with a variable speed transmission serves to encoder 2, which encodes the bits in accordance with the format of the convolutional coding. The encoded symbols are served by the means of repetition of 4 characters. The tool of repetition symbols 4 repeats encoded symbols to provide a fixed baud rate of the symbols provided by means of repetition of 4 characters, regardless of the bit rate information.

Repeated characters serves to block interleaver 6, which changes the sequence, which must be transmitted symbols. The process of alternation, combined with proactive error correction, provides the separation time, which facilitates the reception and error correction of the transmitted signal in the case of batch errors. Peremerzanie symbols are served to the encoder data 12. Encoder data 12 multiplies each displacement is obtained by passing the long PN sequence, generated by long code generator 8, with a baud rate of basic assumptions, through Decimator 10, which selectively generates a subset of the basic assumptions of the long code sequence on the transfer rate of flow perenesennyj characters.

Data from encoder data 12 are served by the demultiplexer (DEMUX) 14. The demultiplexer 14 divides the data stream into three equal components of the flow. The first component stream is fed to the transfer subsystem 15A, the second component of the flow to the transfer subsystem 15b, and the third component of the flow to the transfer subsystem 15C. Subsidry served by the converters of the successive code in parallel (from the binary system in the Quaternary) 16A-16C. The outputs of the converters sequential code in parallel 16A-16C are Quaternary symbols (2 bits/symbol), which must be passed in the format QPSK modulation.

The signals from the serial-to-parallel converters 16A-16C are served to the encoders Walsh 18a-18C. The encoders Walsh 18a-18C signals from each transducer 16A-16C are multiplied by the Walsh sequence consisting of the values +1. Coded according to the system of the Walsh data shall be submitted to the expansion units QPSK 20a-20C which extend the data is due, served by the amplifiers 22A-22b, which amplify the signals in accordance with the gain.

The system described above suffers from many disadvantages. First, because the data must be supplied in equal components of the flow at each of the carrier frequencies available numeric value is limited to personnel with the number of code symbols, which is evenly divided into three. Table 1 below at the end of the description illustrates a limited number of possible sets of relationships, which are available when using the transmission system shown in Fig.1.

As shown in table 1, because the characters are uniformly distributed on the three carrier frequencies, the total data rate is limited by the carrier frequency with the smallest available capacity or requires a higher SNR (signal-to-noise ratio, SNR). That is, the total data rate equal to three times the data rate of the "worst" channel (here means the worst channel, requiring a higher SNR or with the smallest available capacity). This reduces system throughput, because the transmission rate of the worst channel is always selected as the overall transfer rate for all three carrier frequencies that primirenie can greatly affect one of the frequencies, at the same time having little impact on other frequencies. This version does not provide the flexibility and does not allow for the transmission of the frame in a way that reduces the effect of bad channels. Thirdly, thanks dependent on the frequency of the sinking of the sinking will always affect the same group of symbols of each frame. Fourthly, if this performance was imposed on the speech communication system, there would be a good way to balance the load carried on different frequencies based from frame to frame at various loudness of speech in each frame. This leads to a loss in overall system throughput. And fifth, for a system with only three frequency channels, with the implementation described above, there is no way to separate voice and data, so to provide the data on a single frequency or set of frequencies, and the speech on a different frequency or set of frequencies. This leads to loss of system throughput, as mentioned above.

Therefore, there is a need for an improved communication system SOMA with many of bearing, which offers greater flexibility in the quantitative composition and load balancing, more resolution in the supported data rates, and which gives fromhis INVENTION IN one aspect the present invention provides a transmitter for data transmission to the data transmission speed in multiple channels, each of which has a bandwidth less than the data rate, the transmitter includes a controller for determining the bandwidth of each of the multiple channels and selecting a data rate for each channel depending on the specific bandwidth; many subsystems transmit sensitive controller, and each of them is associated with a corresponding channel of the multiple channels for encoding the encoded data codes that are unique to the channel for transmission in the channel; and a variable demultiplexer-sensitive controller, for demuxing encoded data into many subsystems speeds, demuxing, derived from data transmission speeds, the selected channel controller.

In another aspect the invention provides a receiver containing regimen for the reception of signals simultaneously in multiple channels, and each of these signals determines the encrypted encoded symbols, which together represent data from a common source; a controller for determining a symbol rate for the signals in each channel; many subsystems receive sensitive to con avannah character code, unique to the channel, to allow the retrieval of data from it; and AC multiplexer-sensitive controller for multiplexing data from multiple subsystems reception at the speed multiplexing received from the transmission speeds of characters specified by the controller to output channels.

In an additional aspect, the invention provides a radio transmitter that contains the encoder for receiving the set of information bits and encoding the aforementioned bits of information to provide a set of code symbols; and a transfer subsystem for receiving the above code symbols and to supply a subset of the above code symbols at a first carrier frequency and the other symbols on the at least one additional carrier frequency.

The invention also provides a method of transferring data at speeds of data transmission on multiple channels, each of which has a bandwidth less than the data rate, and this method lies in the fact that determine the bandwidth of each of the multiple channels and selects the data rate for each channel depending on the specific bandwidth; provide encryption of the encoded data of Kodolov speed demuxing, derived from data transmission speeds, the selected channel controller.

The invention additionally provides a method of receiving data, namely, that receive signals simultaneously on multiple channels, each of which defines the encrypted encoded symbols, which together represent data from a common source; determine the transmission rate of the symbols for the signals in each channel; provide decoding of encoded symbols in each channel codes that are unique to the channel, to allow the retrieval of data from it; and multiplexer decrypted data from multiple channels at the speed multiplexing received from the transmission speeds of characters specified for channels.

To make best use of the channel resource, you must be able to pass different transmission rate on each carrier frequency according to the channel conditions and the available capacity on each channel. One way to achieve this is to change the relationship of inverse multiplexing on each of the carrier frequencies. Instead of the distribution of characters in the ratio of 1:1:1 can be used over arbitrary ratio with different schemes of recurrence, while pqzii Walsh. The speed of the Walsh functions can be 1228800, 614400, 307200,..., 75 for the length of the Walsh function from 1 to 16384.

When the length of the Walsh function, if the speed of transmission symbols is lower than the speed of the Walsh functions, the repetition of symbols is used to "match" this speed. The repetition factor may be any number, integer or fractional. An experienced specialist will be clear that when the repetition is present, the total transmit power can be reduced to save energy code symbol constant. The length of the Walsh functions may or may not be the same on three carrier frequencies, depending on whether you want us to keep the code channels. For example, if the supported baud rate code symbol on three channels to 153600 SIM/C, 30720 SIM/s and 102400 SIM/s (for exponent coding 1/2 this corresponds to a data transmission speeds 76/8 kbps, 15,36 kbit/s 51.2 kbit/s total data rate 143,36 kbps), then the ratio of the inverse multiplexing is 15:3:10.

If the Walsh code of length 8 is used for all three channels (assuming QPSK modulation rate of the QPSK symbols of 153.6 Ksps/s), each code symbol is transmitted twice, 10 times, and three times on three rope additionally premiani. In an alternate embodiment uses Walsh functions of different length. For example, in the above example, the three channels can be used lengths of 16, 16 and 8, respectively, and each character code is transmitted once on the first channel, five times on the second and three times in the third.

The above approach does not affect the encoder, since it must be able to handle the high data transfer speeds, anyway. The only thing that changes is the number of data octets (bytes) at the input of the encoder. However, this approach affects the performance of the interleaver, because interleaver will have many possible sizes (in terms of number of characters), if allowed all combinations of data rates on three channels. One alternative to the above approach, which mitigates this problem, it is back for multiplexing the code symbols from the encoder to the three bearing frequencies directly and perform interleaving repeated code symbols on each channel separately. This simplifies the selection of numbers and reduces the number of possible dimensions of the interleaver on each channel.

BRIEF DESCRIPTION of DRAWINGS further features, objectives and advantages of the present image is in conjunction with the drawings, in which the same reference characters, respectively, shown in all drawings and in which Fig. 1 is a block diagram illustrating the multi-frequency communication system of CDMA fixed transmission rates and carrier frequencies; Fig. 2 is a block diagram illustrating a transmission system that implements the present invention; Fig.3 is a block diagram illustrating a system embodying the present invention; and Fig. 4 table symbol Walsh code channel in conventional communication system, CDMA IS-95.

A DETAILED DESCRIPTION of the PREFERRED EMBODIMENTS Referring to Fig.2, which is a block diagram illustrating a transmission system embodying the present invention, the first operation that must be performed, determining the amount of data that can be supported on each carrier frequency. In Fig.2 shows three such carrier frequency, while the expert will understand that the present invention can be easily extended to any number of carrier frequencies. Control processor 50 based on a number of factors, such as the load on each of the carrier frequencies, the amount of data queued for transmission to the mobile station, and the priority information that should be passed to the mobile stansiyasi data which should be transmitted to each of the carrier frequencies, control processor 50 selects the modulation format with which data can be transmitted on the selected transmission speed. In an exemplary embodiment uses a Walsh sequence of different length, in order to modulate the data depending on the transfer rate of data that must be transferred. Using Walsh sequences of different lengths selected to modulate the data depending on the transfer rate of data to be transferred is described in detail in concurrently pending application for United States patent serial number 08/654.443, registered on may 28, 1996, entitled "communication System with high data rate", which is passed to the assignee of the present invention and is incorporated here by reference. In an alternate embodiment of the high speed data transfer can be supported by combining the channel CATFISH in the group, as described in the aforementioned patent applications U.S. serial number 08/431.180 and 08/838.240.

After transfer rate that can be supported on each of the carrier frequencies selected, control processor 50 calculates the ratio (proportion) for reverse multipl the tote. For example, if the supported baud rate code symbols on three channels to 153600 SIM/C, 30720 SIM/s and 102400 SIM/s (for the coding rate 1/2 this corresponds to a data transfer rate of 76.8 kbps, 15,36 kbps and 51.2 kbit/s total data rate equal 143,36 kbps), then the ratio (proportion) for inverse multiplexing is 15:3:10.

In the illustrated embodiment, the frames of bits of information served to the device 52 format frames. In the illustrated embodiment of the device 52 format generates and adds to the frame set control bit cyclic redundancy code (CRC). Additionally, the device 52 formatting adds a predefined set of bit shank. The performance and design of devices formatting frames is well known in the art, an example of a typical device format frames are described in detail in U.S. patent number 5.600,754, entitled "Method and system for arrangement of vocoder data for the masking of errors induced by the transmission channel, which is transferred to the assignee of the present invention and is incorporated here by reference.

The formatted data is provided to the encoder 54. In the illustrated embodiment, the encoder 54 is a convolutional code, what about the CPU 50 instructs the encoder 54 number of bits, which must be encoded in the cycle of transmission. In the illustrated embodiment, the encoder 54 is a convolutional encoder with rate coding 1/4 length restrictions 9. It should be noted that due to the additional flexibility provided by the present invention, essentially you can use any encoding format.

The coded symbols from the encoder 54 are served to the demultiplexer 56 with a variable ratio. The demultiplexer 56 with a variable ratio delivers the encoded symbols to the set of outputs on the basis of the signal issuing characters, enjoyed the control processor 50. In the illustrated embodiment there are three carrier frequency and control processor 50 sends a signal indicating the number of encoded characters, which must be served on each of the three outputs. As will be clear to an experienced specialist, the present invention can be easily extended to an arbitrary number of frequencies.

The encoded symbols, filed on each of the outputs of the demultiplexer 56 with a variable ratio, served by appropriate means repeat characters 58A-C. Means repeating characters 58A-C generate duplicate versions of encoded symbols so that the carrier frequency, in particular, match the speed of the Walsh functions used for the carrier frequency. The performance of the generators repetition 58A-C known in the art and an example of such a generator is described in detail in U.S. patent number 5.629.955, entitled "Filter with a variable characteristic that is passed to the assignee of the present invention and is incorporated here by reference. Control processor 50 supplies a separate signal to each generator repetition 58A-C, showing the speed at which characters are transmitted on each carrier frequency, or alternatively, the number of repetitions, which should be provided on each carrier frequency. In response to a signal from control processor means repetition 58A-C generate the required number of repeated characters to ensure that the designated symbol rate. It should be noted that in the preferred embodiment the number of repetitions is not limited to an integer, when all the symbols are repeated the same number of times. The way to ensure a non-integer number of repetitions is described in detail in concurrently pending application for United States patent serial number 08/886.815, registered on March 26, 1997, entitled "Method and apparatus for peridocially of the present invention and is incorporated here by reference.

Characters from generators repetition 58A-s submitted to the appropriate premaritally 60A-60C, which change the order of the repeated symbols in accordance with a predetermined format interleave. Control processor 50 sends a signal format interleave, which specifies one of the predefined formats alternation, each of premaritally 60A-60C. In the illustrated embodiment, the interleave format selected from a predefined set of formats reverse interleave bits.

Characters with the changed order of premaritally 60A-60C are fed to the scrambler data a-s. Each of the data scrambler a-s to change the character data in accordance with psevdochumoy (PN, PN) sequence. Each PN sequence is obtained by passing the long PN code generated by long code generator or PSH 82, with a baud rate of basic assumptions, through Decimator (devices thinning) a-C, which selectively serves some of the expanding symbol to provide a PN sequence with a baud rate of not higher than that provided PSH generator 82. Because the rate at which characters are transmitted on each carrier frequency can otlichatsy fetch and lock choosing the PN sequence from the PN generator 82 and continue to output this value during a predefined period. The performance of the PN generator 82 and decimation a-s well known in the art and are described in detail in the aforementioned U.S. patent number 5.103.459. The data scrambler a-s perform an exclusive OR operation on the binary symbols from premaritally 60A-60C and decimomannu pseudocumene binary sequences from decimation a-s.

Binary scrambling sequence of characters serves to converters sequential code in parallel (from the binary system in the Quaternary) 64A-C. Two binary symbol supplied to the converters 64A-C is converted into a Quaternary group with values (1,1). Group values are provided on the two outputs from the converters a-s. Streams of characters from converters 64A-C are served separately to extenders Walsh 66A-C.

There are many ways to provide high speed data transmission in the communication system, multiple access, code-division multiplexing. In the preferred embodiment the length of the Walsh sequence is changed in accordance with a fast is undertaken for data modulation with a higher speed, and the longer the Walsh sequence used to modulate the data with a lower bit rate. For example, a 64-bit Walsh sequence can be used to transfer data at 19.2 kbit/S. However, 32-bit Walsh sequence can be used to transfer data at 19.2 kbit/S. However, 32-bit Walsh sequence can be used to modulate data at 38.4 kbit/s

The system describing the modulation sequence of variable length Walsh, described in detail in concurrently pending application for United States patent serial number 08/724.281, entitled "an Additional channel with a high data rate CDMA communication system", registered January 15, 1997 and is incorporated here by reference. The length of the Walsh sequences used to modulate the data depends on the data rate that must be transferred. Fig.4 illustrates a Walsh functions in a conventional MC-CDMA IS-95.

In the preferred embodiment of this invention, the number of Walsh channels allocated for high-speed data can be any value 2Nwhere N={2, 3, 4, 5, 6}. Walsh codes used by the encoders Walsh 66A-C, have a length 64/2 characters instead of 64 scanall with 64-symbol Walsh codes, 2Nof the possible 64 quadrature-phase channels with 64-symbol Walsh sequences are excluded from use. Table 2 (see end of description) gives a list of possible Walsh codes for each value of N and the corresponding sets of distributed 64-symbol Walsh codes.

The symbols + and - indicate positive and negative whole value, where a preferred value is 1. As should be clear, the number of characters Walsh in each Walsh code changes with N and in all cases it is less than the number of characters in channel Walsh codes IS-95. Regardless of the length of the Walsh code in the described embodiment of this invention, the symbols are served on speed 1,2288 of Megachips (million elementary parcels) per second (MPP). Thus, shorter Walsh codes are repeated more often. Control processor 50 sends a signal to the coding elements Walsh 66A-C, which indicates a Walsh sequence that should be used to expand the data.

Alternative methods for transmitting high speed data in a CDMA communication system also includes means, generally called the technique of aggregation. The present invention is equally applicable to the methods the United channels is to provide multiple Walsh channels for use by the user signal. This method is described in detail in the aforementioned patent application U.S. serial number 08/739.482. An alternative technique of aggregation is to provide the user the possibility of using a single channel Walsh code, but with the separation of signals from each other through different signal encryption, as described in detail in concurrently pending application for United States patent serial number 08/838.240.

Extended Walsh code data is served to PSH extenders 68A-68 pp., which is applied to the output signals of the expansion of the short PN sequence. In the illustrated embodiment of the PN expansion is performed by multiplication in the complex, as described in the aforementioned concurrently pending application for United States patent serial number 08/784.281. The channels of the data Diand DQmultiplied in a complex way, as the first real and imaginary members, respectively, for extension code PN1and PNqas the second real and imaginary members, respectively, giving the in-phase (or real) member X1and quadrature-phase (or imaginary) member XQ. Extension code PN1and PNQgenerated by generators codes extensions 67 and 69. Extension code PN1and PN+JXQ)=(D1+JDQ) (PN1+JPNQ) (1)
Common-mode member X1then passed through a lowpass filter to the frequency band 1,2288 MHz (not shown) and converted with increasing frequency by multiplying the in-phase carrier COS(ct). Similarly, the quadrature-phase member XQis passed through a lowpass filter to the frequency band 1/2288 MHz (not shown) and converted with increasing frequency by multiplying by the quadrature-phase carrier frequency SIN(ct). Converted with increasing frequency, the members of X1and XQadded together, giving the forward channel signal s(t). Multiplication in the complex form allows you to set the quadrature-phase channels to be orthogonal to the set of in-phase channels and therefore be transmitted without adding additional interference to other channels transmitted on the same path, with a perfect recovery phase of the receiver.

Advanced PSH data is then fed to the filters 70A-70C that the spectral shape of the signal for transmission. The filtered signals are fed to the amplifying tubes 72A - 72s, which amplify the signal for each carrier frequency. Gain 50 gift selects the gain for each carrier frequency in accordance with the condition of the channel and data rate information, which should be passed on this carrier frequency. As is well known, experienced specialist, data that is transmitted by repetition, can be transferred from the lower energy of character, than the data without repetition.

Amplified signals are fed to an optional switch 74. The switch 74 provides additional flexibility forward channel data signals at different carrier frequencies. Typically, the switch 74 is used only when the number of actually used carrier frequencies for transmitting signals less than the total number of possible carrier frequencies (in this example).

Data are ignored by the switch 74 to modulate the carrier frequencies 76A-C. Each of the modulators of the carrier frequencies 76A-C transforms with increasing frequency data in different predetermined frequency. Converted to higher frequency signals are fed to the transmitter 78, where they are combined with other treated in a similar way the signals are filtered and amplified for transmission through the antenna 80. In the illustrated embodiment the enhanced frequency at which each of the signals varies over time. This provides additional diversity in frequency for the transmitted signal is definitely the time interval is switched so that to be transmitted on a different frequency through the modulator carrier frequencies 76b or s. In accordance with a signal from the control processor 50, the switch 74 sends the amplified input signal from the amplifying multiplier 72A-72s to the corresponding modulator carrier frequency 76A-C.

Referring to Fig.3, there is shown a receiver system embodying the present invention. The signal passed in the antenna 100, is passed to a receiver (RCVR) 102, which amplifies and filters the signals before feeding them to the switch 104. The data is fed through switch 104 to the corresponding demodulator carrier frequencies a-s. An experienced specialist will be understood that although the structure of the receiver is described for receiving the signal transmitted on three frequencies, the present invention can be easily extended to an arbitrary number of frequencies, one after the other, or not.

When the carrier frequency on which the data is cyclically shifted or rebuilt abruptly, to provide additional diversity in frequency, the switch 104 supplies the received signal to the selected demodulator carrier frequency a-C in response to the control signal from the control processor 125. When carrying cha is the demodulator carrier frequency a-C demodulates using a quadratic phase shift keying (QPSK) signal into a modulation signal, using different conversion with decreasing frequency, to provide a separate I and Q modulating signals.

Converted to a lower frequency signals from each of the demodulators of the carrier frequency a-s submitted to the appropriate devices PSH compression 108A-s that remove the extension of the short code of the converted to a lower frequency data. The signals I and Q are compressed by multiplication in the complex form on a pair of short PN codes. PSH compressed data are fed to the demodulators Walsh 110A-110S that restores the data in accordance with the assigned sequence code channel. In the illustrated embodiment of the Walsh functions are used in the generation and reception of CDMA signals, but other forms of code generation channel is applicable. Control processor 125 sends a signal to the demodulators Walsh 110A-110S, indicating a Walsh sequence that should be used for data recovery.

Compressed Walsh symbols serves to parallel converters code in serial (4-ary binary) a-s that transform two-dimensional signal in a one-dimensional signal. The symbols are then fed to descrambler a-s. Descrambler a-s descrambling data in southweste long code sequences, used for scrambling data in Fig.2.

Diskriminirovaniya data are fed to the device is turned interleave (DE-INT) 116A-C. The device converts alternation 116A-C change the order of symbols in accordance with the selected formats converted alternation, which serves the control processor 125. In the illustrated embodiment, the control processor 125 sends a signal indicating the size of the device facing the interleave scheme and converted alternation to each of the devices is turned alternation 116A-C. In the illustrated embodiment, the circuit converts the interleave is selected from a predefined set of diagrams drawn alternation with reversing the location of the bits.

Characters subjected to the alternation, then fed to a device combining characters 118a-s that consistently combine the retransmitted symbols. The combined symbols (soft selection) then fed to the multiplexer 120 with a variable ratio, which re-assembles the data stream and sends this newly assembled data stream to the decoder 122. In the illustrated embodiment, the decoder 122 is a decoder for maximum likelihood, which horo is a full frame of data will not be submitted to him, before the start of the decoding process. The decoded frame is supplied to the CRC checker 124, which determines whether the bits of the CRC, and if so, then delivers them to the user, otherwise it is declared failed.

Having thus described the invention by reference to preferred embodiment, it should be well understood that the discussed embodiment is only illustrative, and experienced professionals with relevant knowledge and experience, can be done modifications and changes without deviating from the essence and scope of the invention as set forth in the attached claims and their equivalents.


Claims

1. The transmitter containing an encoder for encoding the set of information bits to provide a set of code symbols with a data rate; a demultiplexer for filing the above set of code symbols in the first and second subsets of code symbols having different transfer speeds of code symbols, the first and second modulators, in which the above-mentioned data transfer rate equal to the United mentioned various transmission speeds of code symbols, and mentioned first and second fashion and second formats speed transmission code symbols, accordingly, these various speed transmission code symbols have a value equal to the number other than one, to provide a modulated first subset of code symbols and a second subset of symbols of the code; a transfer subsystem for the mentioned first subset of the modulated code symbols at a first carrier frequency and the second subset of the modulated code symbols on the second carrier frequency.

2. The radio transmitter under item 1, characterized in that the said first and second modulators repeated code symbols in said first and second subsets of code symbols, respectively, in accordance with the transmission rate of the character code.

3. The radio is in p. 2, characterized in that the transfer subsystem scales corresponding energy of the mentioned first and second subsets of the modulated code symbols in accordance with the appropriate number of repetitions of the code symbols.

4. The radio transmitter under item 1, characterized in that the said first modulator includes a first interleaver, having a first format of the interleaver based on the first speed transmission code symbols, and the second modulator includes a second p the>5. The radio transmitter under item 1, characterized in that the said first modulator includes a first psevdochumoy (PSH) scrambler for scrambling mentioned first subset of code symbols in accordance with the first speed transmission code symbols, and the second modulator includes a second PN scrambler for scrambling mentioned second subset of code symbols in accordance with the second speed transmission code symbols.

6. The radio transmitter under item 1, characterized in that the transfer subsystem includes a switch for selective switching of the mentioned first and second subsets of the modulated code symbols, respectively, on the third carrier frequency.

7. Scheme to modulate the information signal containing the control processor; an encoder for encoding error correction mentioned information signal in accordance with the format specified above mentioned control processor for receiving the coded symbols with a data rate; a demultiplexer with a variable ratio for filing mentioned coded symbols on many modulators with different data rates, and referred to the transmission speed of dannie mentioned various transmission speeds equal to the number other than one, and the aforementioned ratio is selected in response to the control signal from the control processor.

8. The diagram on p. 7, characterized in that at least two of the mentioned multiple modulators modulate mentioned encoded symbols in accordance with various modulation format defined by the mentioned control processor in response to the transmission speed of the characters mentioned coded symbols.

9. The diagram on p. 8, characterized in that each of the said modulator further comprises a repeater of the character to repeat the aforementioned encoded symbols in accordance with the transmission speed of the characters.

10. The diagram on p. 9, characterized in that each of the said modulator further comprises an interleaver to interleave mentioned encoded symbols in accordance with the size of the interleaver defined referred to the control processor.

11. The diagram on p. 10, characterized in that each of the said modulator further comprises a PN scrambler to change the sign mentioned encoded symbols in accordance with a PN sequence, a certain mentioned the control processor in response to UPR is e bug fix mentioned information signal to obtain coded symbols with a data rate; submission-mentioned coded symbols on many modulators with different data rates, and the above-mentioned data transfer rate equal to the combined transfer rate mentioned various speeds, the ratio referred to different data transmission speeds equal to the number other than one; modulation mentioned coded symbols in each of the aforementioned multiple modulators in accordance with different modulation format in response to the transmission speed of the characters mentioned coded symbols.

13. The method according to p. 12, wherein the step of modulating further comprises the step of repeating the aforementioned encoded symbols in accordance with the transmission speed of the characters.

14. The method according to p. 13, wherein the step of modulating further comprises the step of alternation mentioned encoded symbols in accordance with various size of the interleaver.

15. The method according to p. 14, wherein the step of modulating further comprises the step of modifying the character mentioned of encoded symbols in accordance with the PN sequence and in response to the above-mentioned transfer rate of the characters.

 

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The invention relates to computing and communications

The invention relates to electrical connections and may be used to separate channels in communication systems discrete information on parallel channels

FIELD: communications engineering.

SUBSTANCE: proposed band selection method for mobile orthogonal frequency division multiple access communication system includes following steps to classify procedures of band selection between sending end and receiving ends with respect to original band selection process, passband width selection process, and periodic band selection process: determination of source band selection code (SC)number for source band selection process; SC number to request passband width for passband width request selection process and periodic SC number for periodic band selection process; determination of periodic SC deferment value in compliance with periodic SC number, and transmission of source SCs, passband width request SC, periodic SCs, and periodic SC deferment values on receiving ends.

EFFECT: minimized time for band selection access.

22 cl, 3 dwg, 4 tbl

FIELD: communications engineering.

SUBSTANCE: stationary wireless access system has, as a rule, user's room equipment unit connected through Ethernet interface to personal computer or to local network and base station unit connected through Ethernet interface to network. User's room equipment unit as such is easily installed by user while base station unit is usually mounted on mast at distance of 1 to 5 miles (1/6 to 8 km) from user's room equipment unit. Both the latter and base station unit usually incorporate integrated transceiver/data switch that provides for radio-frequency communications in the range of 2.5 to 2.686 GHz. Multiplexing with orthogonal frequency division of signals is used during transmission between user's room equipment units and base station ones over ascending and descending lines.

EFFECT: provision for using outwardly accessible antenna affording transmission within line-of-sight range.

70 cl, 19 dwg

FIELD: electrical and radio communications; underwater, radio, radio-relaying, and meteorological communication lines.

SUBSTANCE: start-stop communication system that has on sending end signal shaping and transfer unit 1 and on receiving end, receiver 2, amplitude detector 3, low-pass filter 4, first comparator 6, memory device 7, shift register 8, first decoder 9, switch 10, synchronizing unit 11, pulse shaper 12, pulse burst shaper 13, binary counters 14, 17, signal retrieval and storage device 19, and threshold device 5 is provided in addition with newly introduced second comparator 15, RS flip-flop 16, and second decoder 18.

EFFECT: reduced malfunction probability of proposed communication system.

1 cl, 3 dwg

FIELD: mobile telecommunication systems.

SUBSTANCE: device for decreasing relation of pike power to average power signal, sent along N(=2r) sub-bearing lines in transmitting device, having encoders for block encoding of w input data, where r - real number > 2, and output of N code symbols, has: serial-parallel converter for transforming data flow to w-(r-2) parallel data flows, where w - length of information word, first coder for receipt of w/2 parallel data flows from w-(r-2) parallel data flows from serial/parallel converter, block encoding of w/2 parallel data flows and output of N/2 first code symbols, generator of input operators for generation of r-2 data flows of input operators, in accordance to w-(r-2) parallel data flows, and second coder for receiving parallel data flows from serial/parallel converter, which were not received at first coder and (r-2) data flows from input operators, block encoding of received data flows and output of N/2 second code symbols, while r-2 data flows of input operators provide for complementarity of N code symbols.

EFFECT: higher efficiency, higher reliability.

6 cl, 22 dwg

FIELD: engineering of devices and methods for receipt and synchronization in direct digital satellite broadcast system.

SUBSTANCE: satellite system uses modulation with temporal signals separation and single-frequency network of ground-based re-emitting stations, each of which introduces a delay to ground signal. Delay allows to provide for coincidence of time of receipt of early modulated signal in the center of ground broadcasting zone with time of receipt of appropriate late modulated signal, thus improving switching between ground and satellite signals in receiver. Delay also compensates processing delay, occurring during conversion of satellite modulated stream under direct visibility conditions to multi-frequency modulated stream for transmission of satellite modulated stream under direct visibility conditions to user receivers. Delay is also adjusted in accordance to distance difference between each ground-based re-emitting station and satellite and between each station and center of ground-based broadcasting zone. Adjustment as described above optimizes receipt of temporal signals separation modulated and multi-frequency modulated signals by means of synchronization in the center of single-frequency system of phase of multi-frequency modulated signals, re-emitted from re-emitting stations of single-frequency system.

EFFECT: increased quality of radio-signal receipt.

8 cl, 12 dwg

FIELD: engineering of devices for generating series of preamble with low ratio of pike to average power in communications system with orthogonal multiplexing and frequency separation of channels.

SUBSTANCE: in accordance to method, first series of preamble is generated, wherein odd data of input series of preamble are transformed to zero data, and even data of aforementioned series are transformed to nonzero data, first series of preamble is transmitted through one of two antennas, second preamble series is generated, wherein even data of input series of preamble are transformed to zero data, and odd data of aforementioned series are transformed to nonzero data, second series of preamble is transmitted through another antenna.

EFFECT: increased efficiency.

6 cl, 10 dwg

FIELD: electric communications engineering, in particular, engineering of multichannel communication systems.

SUBSTANCE: system for transmitting discontinuous information contains at transmitting side information sources, multipliers, adder, clock generator, Walsh functions generator, 2n keys (where 2n - number of outputs of Walsh functions generator) and frequency splitter, two elements of one-sided conductivity and 2n additional multipliers, and on receiving side - clock generator, Walsh functions generator, multipliers, integrators, information receivers, 2n keys and frequency splitter, two elements of one-sided conductivity and 2n additional multipliers. As a new addition, on transmitting side two one-sided conductivity elements are inserted and 2n additional multipliers, and on receiving side - two one-sided conductivity elements and 2n additional multipliers.

EFFECT: decreased frequency band due to decreased effective width of channel carriers spectrum.

6 dwg, 1 tbl

FIELD: engineering of communication systems, using multi-access layout based on orthogonal multiplexing circuit with frequency division.

SUBSTANCE: communication system divides whole range of frequencies onto a set of sub-frequency ranges. Receiver of information about quality of channels receives information about quality of channels for each one of a set of frame cells, occupied during first time span by a set of frequency-time cells, occupied by second time span and a given number of sub-frequency ranges, transferred via check communication channel from receiver. Module for sorting frame cells analyzes information about quality of check communication channels and sorts frame cells in accordance to information about quality of channels. Module for assigning sub-channels, if transfer data exist, transfers data through a frame cell with best channel quality among other frame cells.

EFFECT: increased data transfer speed.

5 cl, 6 dwg

FIELD: electric radio engineering, possible use for increasing quality of electric communication, especially in multi-frequency wireless communication systems.

SUBSTANCE: method for decreasing ratio of peak signal power to its average ratio PAPR in multi-frequency communication systems, in which information symbol is formed by a set of signals, each one of which is centered on one of multiple bearing frequencies, is characterized by the fact that in transmitter a set of bearing frequencies is divided on several sections - subsets of bearing frequencies, information symbol, PAPR value of which does not exceed required threshold PAPR0, is transferred via all carriers, information symbol, value PAPR of which exceeds required threshold PAPR0 is divided on several sub-symbol sections, while number of these sections equals number of sub-carrier subsets, each section of symbol is transferred same as full symbol, wherein data are only transferred on one group of carriers, while other carriers are not modulated, in receiver, arrival of incomplete symbol is identified by analysis of amplitudes of carrier signals, which are not modulated in case of symbol division. Multi-frequency communication system is characterized by construction of receiver and transmitter, adapted for execution of operations, included in proposed method.

EFFECT: preservation of high channel capacity with simplified correction procedure.

2 cl, 12 dwg

FIELD: the invention refers to the field of radio technique and may be used for transmission of information with the aid of signals with orthogonal frequency multiplexing.

SUBSTANCE: the technical result is in increasing accuracy of synchronization of signals with orthogonal frequency multiplexing and that in its turn provides reduction of error possibility at reception of these signals even in such complex propagation conditions as shot-wave range channels. For this in the receiving set of the known equipment two memory blocks, two commutators, a maximum choice selection block, a meter and a time intervals calculation block are introduced.

EFFECT: increases accuracy of signals.

6 dwg

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