JP2004159303A - Code modulation adaptive variable multiplex transmission method and code modulation adaptive variable multiplex transmission apparatus using the method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a code modulation adaptive variable multiplex transmission apparatus capable of efficiently transmitting high-speed information data. <P>SOLUTION: The code modulation adaptive variable multiplex transmission apparatus is provided with: a data dividing circuit 102 for dividing transmission information data into a plurality of subchannel signals, an encoder 104 for selecting a plurality of encoding systems and encoding rates for each subchannel and performing error-correcting encoding; a primary modulator 105 for selecting a plurality of multilevel modulation systems and performing modulation; a secondary modulator 106 for selecting a plurality of band widening systems and widening a band; a transmission condition identification information adding circuit 111 for adding transmission condition identification information indicating the encoding system and the encoding rate for encoding each of subchannels, the multilevel modulation system for primary modulation, and the band widening system and the number of subchannels for secondary modulation; and a frequency multiplexer circuit 114 for frequency-multiplexing a plurality of modulated outputs, and the modulated outputs of the plurality of subchannels are frequency-multiplexed and transmitted. <P>COPYRIGHT: (C)2004,JPO

Description

  The present invention relates to a code modulation multiplex transmission technique, and in particular, to a code modulation capable of efficiently transmitting high-speed information or data in accordance with different transmission conditions such as transmission path conditions, various types of media or various types of services. The present invention relates to an adaptive variable multiplex transmission method and apparatus.

  For transmission information data in a slot unit or a packet unit consisting of a plurality of slots, error correction coding is performed by selecting from a plurality of coding methods and coding rates prepared in advance, and selecting from a plurality of multi-level modulation methods prepared in advance. A conventional code modulation adaptive variable transmission device that performs primary modulation and converts the signal to a transmission signal whose band has been widened by secondary modulation and transmits the signal is disclosed in, for example, JP-A-2000-183849 and JP-A-10-224322. And JP-A-11-234241.

  Further, for related technologies, refer to JP-A-10-145282, WO99 / 14878 (JP-A-2001-517017), and JP-A-9-135275.

  2. Description of the Related Art In multimedia communication in recent years, the demand for Internet traffic has increased dramatically, and the demand for a further high-speed data packet transmission technology has been increasing. In order to realize high-speed data transmission, techniques such as adaptive modulation using multi-level modulation have been introduced, and the coding method and coding rate of an encoder such as the above-described conventional transmission apparatus and the primary A code-modulation-adaptive transmission apparatus using a method of selectively switching the modulation method of a modulator has been devised.

JP 2000-183849 A

JP-A-10-224322 JP-A-11-234241 WO 99/14878 (Japanese Patent Application Laid-Open No. 2001-517017) JP-A-9-135275

  In the following, a description will be given of a code modulation adaptive variable transmission device studied by the inventor of the present invention.

  FIG. 3 shows a configuration of a transmission section of the conventional code modulation adaptive variable transmission device, and FIG. 4 shows a configuration of the reception section.

  First, the configuration of the transmission unit will be described with reference to FIG. In FIG. 3, when transmission information data 301 in units of slots or packets is input, transmission condition identification circuit 306 specifies data rate, data capacity of transmission information data 301 or transmission condition designation information included in the information data. For example, transmission condition information 307 such as data rate and data capacity is identified and output to the transmission unit control circuit 308. The transmission unit control circuit 308 switches the error correction coding method and coding rate of the encoder 303 by using the transmission unit control signal 309 according to the transmission condition information 307, and the multi-level modulation method of the primary modulator 304. , And controls the transmission condition identification information adding circuit 310. Although not shown, there is also a transmission device that includes means for monitoring the propagation status and traffic status of the transmission path, and specifies transmission conditions according to the status of the transmission path to the transmission unit control circuit 308.

  With the above-described control, the input transmission information data 301 is encoded on the transmission channel 302 by the error correction encoding method and encoding rate selected and set by the encoder 303, and further encoded by the primary modulator 304. The transmission condition identification information 311 is added by the transmission condition identification information adding circuit 310 with data that has been primarily modulated by the selected and set multi-level modulation scheme and converted into a command or the like, and the secondary modulator 305 has OFDM (Orthogonal Frequency Division). Multiplex) or spread modulation by a spread code is performed, and the transmission signal 312 is output. The signal 312 transmitted from the transmission channel 302 in this way is received by the receiving unit.

  In the receiving unit in FIG. 4, a received signal 401 is input to a secondary demodulator 403 in a receiving channel 402, and is subjected to secondary demodulation such as OFDM or spread demodulation, and is returned to a multilevel modulated signal. Next, the transmission condition identification circuit 406 identifies the added transmission condition identification information 407, and outputs the identified transmission condition information 408 to the receiving unit control circuit 409. The multi-level demodulation of the primary demodulator 404 is selectively switched by the receiving unit control signal 410 from the receiving unit control circuit 409, and the multi-level modulated signal output from the secondary demodulator 403 is converted into encoded data. Further, the decoding method and the coding rate of the error correction of the decoder 405 are selectively switched, and the coded data is converted from the decoder 405 into the reception information data 411 and output.

  In this transmission device, the modulation method of the secondary modulator 305 is fixed without being selectively switched as in primary modulation.

  However, in order to transmit data at a higher speed in this code modulation adaptive variable transmission apparatus, the processing operations of the encoder, the primary modulator, and the secondary modulator in the transmission channel, as well as the decoder in the reception channel, It is necessary to further speed up the processing operation of the demodulator and the secondary demodulator, and the elements of the processing circuit, and especially the AD (Analog to Digital) converter of the transmission section and the DA (Digital to Analog) Converters need to be developed at higher speeds.

  Further, in high-speed data transmission, in the selection switching of the coding method and coding rate of the encoder and the multi-level modulation method of the primary modulator, various transmission conditions of information data and propagation conditions of a transmission path are used. There is also a problem that fine adaptive control cannot be performed in response to fluctuations in traffic conditions or traffic conditions, and the improvement in frequency use efficiency decreases.

  An object of the present invention is to cope with higher-speed data transmission without speeding up the operations of the encoding and the primary modulation and the secondary modulation of the transmitting unit, or the decoding and the primary and secondary demodulation of the receiving unit. And a code modulation adaptive variable multiplex transmission method and apparatus.

  Another object of the present invention is to provide a code modulation adaptive variable capable of efficiently transmitting higher-speed information data in accordance with different transmission conditions such as transmission path conditions, various types of media or various types of services. A multiplex transmission method and apparatus are provided.

A code modulation adaptive variable multiplex transmission apparatus according to one aspect of the present invention includes:
A data division circuit for dividing data to be transmitted into transmission signals of a plurality of transmission sub-channels,
A primary modulator that is provided for each of the plurality of transmission sub-channels and that performs multi-level modulation on a transmission signal of the transmission sub-channel from the division circuit; and transmits a multi-level modulation signal obtained from the primary modulator. A secondary modulator for widening the band,
Transmission condition information including a multi-level modulation scheme of a primary modulator, a broadband scheme of a secondary modulator, and the number of the plurality of transmission sub-channels for each of the plurality of transmission sub-channels is added to an associated transmission signal. Additional circuit
A frequency multiplexing circuit for frequency-multiplexing the wideband modulated output obtained from each of the secondary modulators of the plurality of transmission sub-channels and outputting the result as a channel for the same user.

  According to a preferred feature of the present invention, the primary modulator provided for each of the plurality of transmission sub-channels is configured to select any one from a plurality of multi-level modulation schemes, The secondary modulator provided for each of a plurality of transmission sub-channels is configured to select an arbitrary one from a plurality of broadband schemes.

  According to another preferred feature of the present invention, a code for performing error correction coding on the transmission signal of an associated transmission sub-channel at a stage preceding the primary modulator provided for each of the plurality of transmission sub-channels. And the primary modulator performs multi-level modulation on output data from the encoder.

  According to another preferred feature of the present invention, the encoder is configured to select any one of a plurality of error correction coding schemes and a plurality of coding rates.

Also, a code modulation adaptive variable multiplex transmission apparatus according to another aspect of the present invention,
A frequency separation circuit that frequency-divides the received frequency multiplexed signal into modulated signals for each of a plurality of reception sub-channels,
A transmission condition identification circuit for identifying transmission condition information including a primary modulation multilevel modulation system, a secondary modulation broadband system, and the number of reception subchannels in a signal for each reception subchannel added on the transmission side. When,
A control circuit for generating a control signal based on the transmission condition information identified in the transmission condition identification circuit,
Provided for each of a plurality of reception sub-channels, in response to the control circuit, the modulation signal of the relevant reception sub-channel obtained from the frequency separation circuit to the wideband system identified by the transmission condition identification circuit In response to the secondary demodulator for demodulating in the corresponding inverse wideband system and the control circuit, the modulated signal for each reception channel demodulated by the secondary demodulator is multi-valued by the transmission condition identification circuit. A primary demodulator for demodulating by a multi-level demodulation method corresponding to the modulation method;
A data combining circuit for combining data obtained from the plurality of receiving sub-channels.

Also, a code modulation adaptive variable multiplex transmission method according to another aspect of the present invention,
Dividing data to be transmitted into transmission signals of a plurality of transmission sub-channels;
Performing multi-level modulation on each of the transmission signals of the plurality of transmission sub-channels,
Performing a broadband for each of the multi-level modulation signals of the plurality of transmission sub-channels,
A step of adding transmission condition information including a modulation scheme of the multi-level modulation, a broadband scheme of the transmission band, and the number of the transmission sub-channels to an associated transmission signal,
Frequency multiplexing the modulated outputs of the plurality of transmission sub-channels and outputting the same as a channel for the same user.

  In the above-described code modulation adaptive variable multiplex transmission apparatus according to the present invention, the transmission unit divides transmission information data into a plurality of subchannels, and selects and switches an error correction coding method and a coding rate for each transmission subchannel. In order to perform the primary modulation of the multi-level modulation scheme selectively switched and the secondary modulation of the wideband scheme selectively switched, the processing operation of each transmission sub-channel is performed by dividing the transmission sub-channel into a plurality of sub-channels. The speed is reduced, so that higher-speed data transmission can be supported. Similarly, also in the receiving unit, the processing operations of the secondary demodulation, the primary demodulation, and the error correction decoding for each reception sub-channel after separating the reception signal are reduced in speed, so that higher-speed data transmission can be supported. . That is, the AD converter and the DA converter used for the encoding and the primary modulation and the secondary modulation of the transmitting unit or the decoding and the primary and secondary demodulation of the receiving unit can be supported by the low-speed elements.

  In addition, switching of the coding method and coding rate of the encoder, and selection and switching of the multi-level modulation method of the primary modulator, switching of the number of sub-channels, and switching of the broadband method of the secondary modulator are also performed. By performing this in combination, it is possible to perform fine adaptive control in response to various transmission conditions, fluctuations in the propagation conditions of the transmission path, and changes in the traffic conditions, thereby further improving the frequency use efficiency.

  Therefore, it is possible to efficiently transmit higher-speed information data in accordance with different transmission conditions such as transmission path conditions, various media, and various services.

  As described above, according to the present invention, the processing operations of encoding and primary modulation and secondary modulation of a transmitting unit, or decoding and primary demodulation and secondary demodulation of a receiving unit are slowed down, and it is difficult to increase the speed. A simple AD converter and DA converter can be supported by low-speed elements, and a transmission device that can support higher-speed data transmission can be realized.

  Further, according to the present invention, it is possible to perform finer adaptive control in response to various transmission conditions, fluctuations in the propagation conditions and traffic conditions of the transmission path, and to adapt to different transmission conditions such as various media or various services. Correspondingly, a transmission device capable of efficiently transmitting higher-speed information data can be realized.

  According to the present invention, information data is divided into a plurality of sub-channel signals, a plurality of sub-channels are frequency-multiplexed and transmitted as the same user channel, the embodiment of the code modulation adaptive variable multiplex transmission apparatus of the present invention, This will be described with reference to FIGS.

  FIG. 1 is a block diagram showing a configuration of a transmission unit of a code modulation adaptive variable multiplex transmission apparatus according to an embodiment of the present invention. The transmission unit identifies transmission condition information 108 based on the input data rate, data capacity of transmission information data 101 in slot or packet units, or transmission condition designation information included in the information data. A transmission unit control circuit 109 to which the transmission condition information 108 identified by the transmission condition identification circuit 107 is supplied; and a transmission unit control signal 110 from the transmission unit control circuit 109 to transmit the transmission information data 101 to a plurality of transmission sub-units. A data division circuit 102 for dividing the data into channels (1) to (n) 103 and a transmission unit control signal 110 from a transmission unit control circuit 109 prepare in advance in each of the transmission subchannels (1) to (n) 103 (code Coding methods (convolutional coding, Reed-Solomon, BCH, etc.) ) And an encoder 104 for selectively switching an encoding rate to perform error correction encoding according to a desired encoding method and encoding rate, and a transmission unit control according to transmission condition information 108 from a transmission unit control circuit 109. According to the signal 110, a plurality of multi-level modulation schemes (modulation schemes such as QPSK including BPSK and 16QAM) prepared in advance (provided as a modulator circuit) in each of the transmission sub-channels (1) to (n) 103. A primary modulator 105 that selectively performs switching and performs primary modulation according to a desired multi-level modulation scheme, and transmission condition identification information 112 corresponding to transmission condition information 108 set by the transmission unit control circuit 109 are transmitted to each transmission subchannel ( 1) to (n), a transmission condition identification information adding circuit 111 added to the transmission signal and a transmission unit control signal 110 from the transmission unit control circuit 109 are used to transmit each transmission sub-channel. In (1) to (n) 103, a wideband system such as OFDM (Orthogonal Frequency Division Multiplex) or spread modulation (spread spectrum) prepared in advance (provided as a modulator circuit) is selectively switched to achieve a desired wideband. It comprises a secondary modulator 106 that performs secondary modulation according to a system, and a frequency multiplexing circuit 114 that frequency multiplexes a transmission modulation signal 113 obtained from a plurality of transmission sub-channels (1) to (n) 103.

  FIG. 6 shows a configuration example of the encoder 104. The coder 104 uses a transmission control signal 110 from the transmission control circuit 109 to prepare a desired code from a plurality of coding schemes (encoding schemes such as convolutional coding, Reed-Solomon, and BCH) prepared in advance and a coding rate. It is configured to select a coding scheme and a coding rate.

  FIG. 7 shows a configuration example of the primary modulator 105. The primary modulator 105 is configured to select a desired multi-level modulation scheme from a plurality of multi-level modulation schemes (BPSK, QPSK, 16QAM, etc.) prepared in advance by a transmission control signal 110 from a transmission control circuit 109. I have.

  FIG. 8 shows a configuration example of the secondary modulator 106. The secondary modulator 106 is configured to select a desired broadband system from a plurality of wideband systems (OFDM, spread modulation (spread spectrum), etc.) prepared in advance by a transmission control signal 110 from a transmission control circuit 109. ing.

  The data division circuit 102 divides the transmission information data 101 into a plurality of transmission sub-channels (1) to (n) 103 at equal or different rates by a transmission unit control signal 110 based on the transmission condition information 108 from the transmission unit control circuit 109. It is a circuit to divide. For example, if the data division circuit 102 is equally divided in the case of four sub-channels, the data division circuit 102 divides one by one into each sub-channel every time four pieces of transmission information data are input, and different ratios (for example, 1 : 2: 3: 4), every time 10 pieces of transmission information data are input, each of the four sub-channels is divided into 1, 2, 3, and 4 data. Will be split. The term “sub-channel” is used because a plurality of channels are frequency-multiplexed and used by one user as one channel.

  Here, the encoder 104, the primary modulator 105, and the secondary modulator 106 are required for each of the transmission sub-channels (1) to (n) 103. The transmission condition identification information adding circuit 111 adds the transmission condition identification information 112 to each of the transmission sub-channels (1) to (n) 103 or to one or more transmission sub-channels designated collectively (see FIG. The transmission condition identification information 112 is added as abbreviated data such as a command). Then, the transmission condition identification information 112 is fixedly added to the system specified and determined in advance by the transmitting side and the receiving side on the broadband system of the secondary modulator 106.

  When transmission information data 101 in units of slots or packets is input to the transmission unit configured as described above, the transmission condition identification circuit 107 determines the data rate and data capacity of the transmission information data 101 or the transmission conditions included in the information data. Encoding method (convolutional code [convolutional code], Reed-Solomon [Reed-Solomon code], BCH [Bose-Chaudhuri-Hocquenghem code], etc.] ) And the coding rate, the primary modulation multi-level modulation scheme, the secondary modulation broadband scheme, and the transmission condition information 108 indicating the number of sub-channels to be divided and multiplexed. The condition information 108 is output to the transmission unit control circuit 109. Note that convolutional coding is a type of error correction code that generates a code based on a plurality of information blocks. This code has been developed in connection with a decoding method. There is a maximum likelihood decoding method.). Reed-Solomon is a type of error correction code. It is one of the block code systems for detecting and correcting burst errors. It is used in communication and data recording. And a method of adding a parity bit (bit for error detection) for each block. In addition, there is a fire code for burst error detection / correction, and a method for random error correction. , A BCH code, a Hamming code, a cyclic code, a Golay code, etc. In addition to the block coding method, there is a convolutional code. Without performing the division, a method of performing an exclusive OR operation or the like is performed for each of several input bits.) Here, the transmission condition identification circuit 107 may receive the transmission condition information 210 from the transmission condition identification circuit 208 of the receiving unit described later and output the transmission condition information 108 to the transmission unit control circuit 109. Although not shown, means for monitoring the propagation state and traffic state of the transmission line may be provided, and the transmission condition information 108 according to the state of the transmission line may be output to the transmission unit control circuit 109.

  The transmission unit control circuit 109 controls the data division circuit 102 to divide the transmission information data 101 into the transmission sub-channels (1) to (n) 103 at equal or different rates by the transmission condition information 108. For each of the transmission sub-channels (1) to (n) 103, the coding scheme and coding rate of the encoder 104, the multi-level modulation scheme of the primary modulator 105, and the wideband scheme of the secondary modulator 106 Is controlled in accordance with the transmission condition information 108, and the transmission condition identification information adding circuit 111 is controlled to add the transmission condition identification information 112 to be transmitted to the transmission signal. According to the above control, the transmission information of each transmission sub-channel 103 is input to the encoder 104 and is encoded by the selected and switched coding scheme and coding rate, and the multi-valued data is selectively switched by the primary modulator 105. The transmission condition identification information 112 that has been primarily modulated by the modulation method and converted into a command or the like is added in the transmission condition identification information addition circuit 111. Next, secondary modulation is performed by the secondary modulator 106 in the selected and switched wideband system, and a transmission modulation signal 113 is output.

  Then, the transmission modulation signals 113 from the plurality of transmission sub-channels 103 are frequency-multiplexed by the frequency multiplexing circuit 114, transmitted as transmission multiplexed signals 115, and received by the receiving unit.

  Next, the frequency multiplexing in the frequency multiplexing circuit 114 will be described with reference to the frequency multiplexing example of the sub-channel modulation signal shown in FIGS. Frequency multiplexing is a process of multiplying a modulated signal of each sub-channel by a carrier signal and arranging the modulated signals in the frequency direction so that the channel band of each modulated sub-channel does not become large.

  FIG. 9 shows a case where the channel bandwidths of the sub-channel modulated signals are equally spaced, and the sub-channel modulated signals are multiplied by equally spaced carrier signals, and are arranged at regular intervals in the frequency direction and multiplexed. Convert to one signal.

  As shown in FIG. 10, the sub-band modulated signals having different numbers of sub-carriers in the OFDM modulation scheme have different channel bandwidths. Therefore, the carrier signals having different frequency intervals are multiplied by the respective sub-channel modulated signals to obtain the channel bandwidth. Are arranged in the frequency direction so that they do not overlap, multiplexed, and converted into one signal.

  In all of the plurality of transmission sub-channels (1) to (n) 103 to be multiplexed described in the above embodiment, the same coding scheme and coding rate are used as encoder 104, and primary modulator 105 , The same multi-level modulation scheme may be used, and the secondary modulator 106 may use the same wideband scheme. In this case, based on the transmission unit control signal 110 obtained from the transmission unit control circuit 109, the encoder 104 may, of course, select and use the same encoding method and encoding rate, The same multi-level modulation scheme may be selected and used as the modulator 105, and the same wideband scheme may be used as the secondary modulator 106.

  Also, a large number of transmission sub-channels (1) to (n) 103 to be multiplexed shown in the above embodiment are divided into a plurality of groups corresponding to a plurality of users, for example, and a plurality of In the sub-channel, the same coding scheme and coding rate may be used as encoder 104, the same multi-level modulation scheme may be used as primary modulator 105, and the same wideband scheme may be used as secondary modulator 106. . Also in this case (even in a plurality of sub-channels of each divided group), the same coding scheme and code as the encoder 104 are used based on the transmitter control signal 110 obtained from the transmitter controller 109. The modulation rate may be selected and used, the same multi-level modulation scheme may be selected and used as the primary modulator 105, and the same wideband scheme may be used as the secondary modulator 106. Is also good.

  FIG. 2 is a block diagram showing a configuration of a receiving section of one embodiment of the code modulation adaptive variable multiplex transmission apparatus according to the present invention. The receiving section includes a frequency separation circuit 202 for frequency-separating the received multiplexed signal 201 into reception modulation signals 203 of the respective reception sub-channels (1) to (n) 204, and a reception sub-channel (1) added on the transmission side. ) To (n) 204: Transmission condition identification for identifying transmission condition information 210 for error correction coding system, coding rate, multi-level modulation system for primary modulation, wideband system for secondary modulation, and number of sub-channels. A receiving unit control circuit 211 for controlling the secondary demodulator 205, the primary demodulator 206, and the decoder 207 and controlling the data synthesizing circuit 213 for each reception sub-channel based on the circuit 208 and the identified transmission condition information 210; , A data synthesizing circuit 213 for synthesizing information data from the plurality of reception sub-channels (1) to (n) 204. Here, the secondary demodulator 205, the primary demodulator 206, and the decoder 207 are required for each of the reception sub-channels (1) to (n) 204.

  When the reception multiplexed signal 201 is input to the receiving unit configured as described above, the frequency separation circuit 202 separates the received multiplexed signal 201 into reception modulation signals 203 of a plurality of reception sub-channels (1) to (n) 204, In the secondary demodulator 205 of the channels (1) to (n) 204, the signal is subjected to the secondary demodulation by the inverse wideband system selected and switched by the reception unit control circuit 211, and is returned to the primary modulation signal. Note that the number n of reception sub-channels is the number of sub-channels included in the identified transmission condition information 210.

  The primary modulation signal is supplied to the transmission condition identification circuit 208, where the transmission condition identification information 209 added in the transmission unit is identified, and the transmission condition information 210 is input to the reception unit control circuit 211. In the receiving unit control circuit 211, the band widening system of the secondary modulator 106, the multi-level modulation system of the primary modulator 105, and the encoding system of the encoder 104 in each transmission sub-channel 103 of the transmission unit according to the transmission condition information 210. And the decoding rate of the secondary demodulator 205, the multi-level demodulation method of the primary demodulator 206, and the decoding of the decoder 207 in each of the reception subchannels (1) to (n) 204 so as to match the coding rate. Control for selectively switching between the system and the coding rate is performed.

  As described in the description of the transmission unit, the transmission condition identification information 209 is fixedly added to the system specified in advance in the transmission side and reception side on the broadband system of the secondary modulator 106, so that the secondary demodulation is performed. The reverse band widening method of the device 205 is switched to a method prearranged and specified for the transmission condition identification information 209 and to a method based on the transmission condition information 210 for information data. Also, the transmission unit adds transmission condition identification information to each transmission sub-channel or to one or more transmission sub-channels designated collectively, so that the reception unit From the transmission condition identification circuit 208 by the transmission condition identification circuit 208.

  The primary modulation signal output from the secondary demodulator 205 is subjected to primary demodulation in the primary demodulator 206 by the multi-level demodulation method selectively switched by the reception control signal 212 from the reception control circuit 211, and further decoded. The signal is decoded by the decoding method and the coding rate selected and switched in the unit 207, and the reception information of each of the reception sub-channels (1) to (n) 204 is reproduced. The reception information of the plurality of reception sub-channels (1) to (n) 204 is synthesized by the data synthesis circuit 213, and the reception information data 214 is output.

  The transmission method of the transmission condition identification information 112 from the transmission unit to the reception unit includes the following method. The first method is that, when information data is transmitted in a slot or a packet of a plurality of slots, the transmission condition identification information 112 is added to the head (header) of the slot or packet, and the data is transmitted. In the second method, transmission condition identification information 112 is added to a code-multiplexed or frequency-multiplexed pilot channel and the like, and the transmission condition information is identified from the received pilot channel. How to As still another method, there is a method of transmitting the transmission condition identification information 112 in the immediately preceding slot or packet.

  FIG. 5 is a diagram showing an example of a packet transmission timing operation between the stations A and B each having the transmitting section (FIG. 1) and the receiving section (FIG. 2). Here, it is assumed that each station transmits data in a packet unit such as a slot composed of a plurality of transmission data or a frame composed of a plurality of the above-described slots. The transmission condition information is added to the transmission portion. In FIG. 5, the horizontal axis is a time axis, (a) is transmission data of station A, (b) is reception data of station B, (c) is transmission data of station B, and (d) is reception of station A. Shows the data. Here, in the initial state, it is assumed that the number of multiplexed channels, primary modulation, and secondary modulation used for transmission of the information from the station A have been set to the initial setting values which are predetermined according to the type of the data. .

  As shown in FIG. 5A, the station A transmits a transmission packet A1 having transmission condition information and data a1, which is received by the station B as shown in FIG. 5B. In the transmission condition identification circuit 208 in the receiving unit of the station B, the transmission condition information included in the transmission packet A1 is extracted and supplied to the transmission unit control circuit 109. As a result, as shown in (c), the B station transmits its own transmission packet B1 by the set primary modulation and secondary modulation using the number of channels set by the transmission condition information. A signal-to-interference noise power ratio is calculated from a received signal of the received transmission packet A1 by a signal-to-interference noise power ratio calculation circuit (not shown) in the receiving unit of the station B, and based on the calculation result and the like. A return transmission channel transmission condition determining circuit (not shown) generates return transmission channel transmission condition information, stores it in a reception channel transmission condition information memory (not shown), and adds transmission condition identification information of the transmission unit. The signal is supplied to the circuit 111. As a result, as shown in (c), the return transmission channel transmission condition information is added to the transmission packet B1 transmitted by the station B and transmitted.

  As shown in FIG. 5D, the transmission packet B1 is received by the station A, and is extracted by the transmission condition identification circuit 208 by the reception unit of the station A in the same manner as the reception unit of the station B. Based on the transmission condition information, the number of multiplexed channels, primary modulation, and secondary modulation of the next transmission packet A2 are set. Further, the transmission condition information to be specified for the station B is generated by the loopback transmission channel transmission condition determination circuit, added to the transmission packet A2, and transmitted. The station B that has received the transmission packet A2 takes out the transmission condition information stored in the transmission packet and sets it in the control circuit 109 of the transmission unit in the same manner as described above. Generate transmission condition information. At this time, the secondary demodulator 205 and the primary demodulator 205 are used by using the return transmission channel transmission condition information generated when the transmission packet A1 is received and stored in the reception channel transmission condition information memory (not shown). The demodulator 206 and the data synthesis circuit 213 are set.

  In the code modulation adaptive variable multiplex transmission apparatus according to the present invention described above, the transmission unit divides transmission information data into a plurality of sub-channels, performs error correction coding for each transmission sub-channel, In order to perform the modulation and the secondary modulation of the broadband method, the processing operation of each transmission sub-channel is slowed down by dividing it into a plurality of sub-channels. Similarly, also in the receiving section, the processing operations of the secondary demodulation, the primary demodulation, and the decoding for each reception sub-channel after separating the reception signal are reduced. The AD converter and the DA converter in the encoder, the primary modulator and the secondary modulator, or the secondary demodulator and the primary demodulator and the decoder can be supported by low-speed elements.

  In addition, the switching of the number of sub-channels and the switching of the wideband system of the secondary modulator are performed in combination with the selection and switching of the encoding system and coding rate of the encoder and the multi-level modulation system of the primary modulator. Thus, fine adaptive control can be performed in response to various transmission conditions, fluctuations in the propagation conditions of the transmission path, and traffic conditions, and the frequency use efficiency can be further improved.

  Therefore, it is possible to efficiently transmit higher-speed information data in accordance with different transmission conditions such as transmission path conditions, various media, and various services.

FIG. 2 is a block diagram illustrating a configuration of a transmission unit of the code modulation adaptive variable multiplex transmission apparatus according to one embodiment of the present invention. FIG. 2 is a block diagram illustrating a configuration of a receiving unit of one embodiment of the code modulation adaptive variable multiplex transmission apparatus according to the present invention. FIG. 3 is a block diagram illustrating a configuration of a transmission unit of a code modulation adaptive variable transmission device studied in the course of performing the present invention by the inventor. FIG. 2 is a block diagram illustrating a configuration of a receiving unit of the code modulation adaptive variable transmission device studied in the course of performing the present invention by the inventor. It is a figure which shows an example of the packet transmission / reception timing operation | movement in one Example of the code modulation adaptive variable multiplex transmission apparatus of this invention. FIG. 2 is a block diagram illustrating a configuration of an example of an encoder of a transmission unit of the code modulation adaptive variable multiplex transmission device of FIG. 1. FIG. 2 is a block diagram illustrating an example of a configuration of a primary modulator of a transmission unit of the code modulation adaptive variable multiplex transmission apparatus of FIG. 1. FIG. 2 is a block diagram illustrating an example of a configuration of a secondary modulator of a transmission unit of the code modulation adaptive variable multiplex transmission device of FIG. 1. FIG. 2 is a diagram for explaining an example of sub-channel frequency multiplexing in a frequency multiplexing circuit of a transmission unit of the code modulation adaptive variable multiplex transmission device of FIG. 1. FIG. 2 is a diagram for explaining another example of sub-channel frequency multiplexing in a frequency multiplexing circuit of a transmission unit of the code modulation adaptive variable multiplex transmission device of FIG. 1.

Explanation of reference numerals

101: transmission information data, 102: data division circuit, 103: transmission sub-channel, 104: encoder, 105: primary modulator, 106: secondary modulator, 107: transmission condition identification circuit of the transmission unit, 108: Transmission condition information of the transmission unit, 109: Transmission unit control circuit, 110: Transmission unit control signal, 111: Transmission condition identification information addition circuit, 112: Transmission condition identification information of the transmission unit, 113: Transmission modulation signal, 114: Frequency multiplexing , 115: transmission multiplex signal, 201: reception multiplex signal, 202: frequency separation circuit, 203: reception modulation signal, 204: reception subchannel, 205: secondary demodulator, 206: primary demodulator, 207: decoding 208: Transmission condition identification circuit of the receiving unit, 209: Transmission condition identification information of the receiving unit, 210: Transmission condition information of the receiving unit, 211: Control unit of the receiving unit , 212: receiving unit control signal, 213: data combining circuit, 214: received information data.

Claims (6)

A data division circuit for dividing data to be transmitted into transmission signals of a plurality of transmission sub-channels,
A primary modulator that is provided for each of the plurality of transmission sub-channels and that performs multi-level modulation on a transmission signal of the transmission sub-channel from the division circuit; and transmits a multi-level modulation signal obtained from the primary modulator. A secondary modulator for widening the band,
Transmission condition information including a multi-level modulation scheme of a primary modulator, a broadband scheme of a secondary modulator, and the number of the plurality of transmission sub-channels for each of the plurality of transmission sub-channels is added to an associated transmission signal. Additional circuit
A frequency multiplexing circuit for frequency-multiplexing a wideband modulated output obtained from each of the secondary modulators of the plurality of transmission sub-channels and outputting the multiplexed output as a channel for the same user. Multiplex transmission equipment.   2. The method according to claim 1, wherein the primary modulator provided for each of the plurality of transmission sub-channels is configured to select an arbitrary one from a plurality of multi-level modulation schemes. A code modulation adaptive variable multiplex transmission apparatus, wherein the secondary modulator provided for each is configured to select an arbitrary one from a plurality of broadband schemes. A control circuit that generates a control signal based on transmission condition information;
A data division circuit for dividing data to be transmitted into transmission signals for each of a plurality of transmission sub-channels,
A primary modulator that is provided for each of the plurality of transmission sub-channels, selects one multi-level modulation scheme from a plurality of multi-level modulation schemes in response to the control circuit, and modulates a related transmission signal; A secondary modulator that selects one broadband system from a plurality of wideband systems in response to a control circuit, and widens a multi-level modulation signal obtained from the primary modulator;
An additional circuit for adding transmission condition information including a modulation scheme of a primary modulator, a broadband scheme of a secondary modulator, and the number of the transmission sub-channels to a related transmission signal for each of the plurality of transmission sub-channels; ,
A frequency multiplexing circuit for frequency-multiplexing a wideband modulation output obtained from each of the secondary modulators of the plurality of transmission subchannels and outputting the multiplexed output as a channel of the same user. Multiplex transmission equipment. A frequency separation circuit that frequency-divides the received frequency multiplexed signal into modulated signals for each of a plurality of reception sub-channels,
A transmission condition identification circuit for identifying transmission condition information including a primary modulation multilevel modulation system, a secondary modulation broadband system, and the number of reception subchannels in a signal for each reception subchannel added on the transmission side. When,
A control circuit for generating a control signal based on the transmission condition information identified in the transmission condition identification circuit,
Provided in each of a plurality of reception sub-channels, in response to the control circuit, a transmission band of a modulation signal of an associated reception sub-channel obtained from the frequency separation circuit, a wide band identified by the transmission condition identification circuit. In response to the secondary demodulator that demodulates by the inverse wideband system corresponding to the demodulation system and the control circuit, the modulation signal for each reception channel demodulated by the secondary demodulator is identified by the transmission condition identification circuit. A primary demodulator for demodulating with a multi-level demodulation scheme corresponding to the multi-level modulation scheme,
A data combining circuit for combining data obtained from the plurality of receiving sub-channels. Dividing data to be transmitted into transmission signals of a plurality of transmission sub-channels;
Performing multi-level modulation on each of the transmission signals of the plurality of transmission sub-channels,
Performing a broadening of the transmission band for each of the multi-level modulation signals of the plurality of transmission sub-channels,
A step of adding transmission condition information including the modulation scheme of the multi-level modulation, the wideband scheme, and the number of the transmission sub-channels to an associated transmission signal,
Frequency multiplexing the modulated outputs of the plurality of transmission sub-channels and outputting the same as a channel for the same user. Using a frequency separation circuit, frequency dividing the received frequency multiplexed signal into a modulated signal for each of a plurality of receiving sub-channels,
A transmission condition identification circuit identifies transmission condition information including a multi-level modulation system of primary modulation, a broadband system of secondary modulation, and the number of reception subchannels in a signal for each reception subchannel added on the transmission side. Steps and
A secondary demodulator provided for each of the plurality of reception sub-channels, the modulation signal for each reception sub-channel obtained from the frequency separation circuit corresponding to the wideband system identified by the transmission condition identification circuit Demodulating with an inverse wideband system,
In the primary demodulator provided for each of the plurality of reception sub-channels, a modulation signal for each reception channel demodulated by the secondary demodulator is converted into a multi-level modulation scheme identified by the transmission condition identification circuit. Demodulating with a corresponding multi-level demodulation scheme;
Combining the data obtained from the plurality of reception sub-channels.

Images