JP2006093897A - Communication device, base station device, and transmission method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve reception characteristics by selecting an optimum interleaving method. <P>SOLUTION: A chip interleaver selector 105 selects a pattern in chip interleaving, on the basis of propagation channel information, such as delay spread. A signal synthesizer 115 performs the code multiplexing or user multiplexing of chip data among chips, and generates code-multiplexed chip data in a plurality of chip units. A chip interleaver 116 sorts chip data for each chip, on the basis of pattern information in chip interleaving. A frequency converter 117 performs inverse FFT to the code-multiplexed chip data in a plurality of chip units, arranges each code-multiplexed chip data to each corresponding subcarrier, and generates an MC-CDMA signal. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a communication apparatus, a base station apparatus, and a transmission method, and particularly to a communication apparatus, a base station apparatus, and a transmission method having an adaptive interleaving function.

  Conventionally, a communication system having an adaptive interleaving function that dynamically selects a suitable interleaving method based on various factors in a network is known (for example, Patent Document 1). Such a communication system includes a symbol interleaver, a bit interleaver, and a chip interleaver, and adaptively selects an interleaver having optimal reception characteristics according to the number of code multiplexes or the spreading factor.

  Interleaving is a technique for randomizing such a burst error because a random error correction code such as a turbo code cannot fully exhibit its ability when a burst error occurs due to multipath fading. There are the following three types of typical interleaving. The first is symbol interleaving, in which interleaving is performed on a data modulation symbol sequence. Symbol interleaving can improve the reception characteristics regardless of the propagation channel conditions and the data modulation scheme, and the burst error can be randomized as the interleaving length increases, so that the effect of improving the reception characteristics is great.

  The second is bit interleaving, in which interleaving is performed on a bit (coded bit) sequence after channel coding. Bit interleaving can improve reception characteristics regardless of propagation channel conditions and modulation schemes, and the larger the interleaving length, the more random burst errors can be achieved.

  The third is chip interleaving, which is performed on a chip sequence after multiplication by spreading codes. Chip interleaving interleaves on a chip-by-chip basis to disrupt frequency coherence or temporal coherence, so that the diversity effect, ie, SINR (Signal to Interference and Noise Ratio) per symbol before chip interleaving. However, since the frequency coherence or time coherence in a symbol is collapsed, inter-code interference occurs due to the collapse of orthogonality between spreading codes. However, in the case of a single code, inter-code interference does not occur, and furthermore, the reception characteristics are greatly improved by improving the frequency diversity effect or the time diversity effect, which is very effective. Unlike bit interleaving and symbol interleaving, chip interleaving does not necessarily improve reception characteristics, and reception characteristics greatly depend on propagation channel conditions, spreading factor, number of code multiplexes, and data modulation schemes. It is difficult.

The purpose of bit interleaving is to obtain a frequency interleaving effect by randomizing the channel gain received by the encoded bit sequence input to the error correction decoder, and chip interleaving reduces the inter-chip correlation within a symbol. The purpose is to obtain a frequency diversity effect by despreading. Therefore, normally, bit interleaving and chip interleaving are used together.
JP 2004-72772 A

  However, in the conventional apparatus, since the interleaving method is selected based only on the number of code multiplexes or the spreading factor, there is a problem that the optimum interleaving method cannot be selected and the reception characteristics cannot be improved.

  The present invention has been made in view of the above points, and an object thereof is to provide a communication apparatus, a base station apparatus, and a transmission method that can improve reception characteristics by selecting an optimal interleaving method.

  The communication apparatus according to the present invention includes a spreading unit that spreads symbol data with a spreading code to generate chip data, and an arrangement that rearranges the chip data generated by the spreading unit for each chip based on a propagation path environment. A transposing means, a converting means for arranging the chip data rearranged for each chip by the rearranging means in each subcarrier for each chip, and a chip data arranged in each subcarrier by the converting means is transmitted. And a transmission means.

  The transmission method of the present invention includes a step of spreading the symbol data with a spreading code to generate chip data, a step of rearranging the generated chip data for each chip based on a propagation path environment, and a row for each chip. A step of arranging the replaced chip data on each subcarrier for each chip and a step of transmitting the chip data arranged on each subcarrier are provided.

  According to the present invention, reception characteristics can be improved by selecting an optimal interleaving method.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment 1)
FIG. 1 is a block diagram showing a configuration of communication apparatus 100 according to Embodiment 1 of the present invention. Information data generation unit 107, channel encoding unit 108, bit interleaving unit 109, data modulation unit 110, serial-parallel conversion unit 111, symbol duplication units 112-1 to 112-n, spreading code generation unit 113, and multiplier 114-1 −1 to 114-n−k (k = spreading factor SF) constitute the signal processing units 120-1 to 120-u. The signal processing units 120-1 to 121-u are provided in the same number as the number of communication terminal devices (users), and process signals to be transmitted to each communication terminal device.

  The antenna 101 transmits the transmission signal input from the transmission RF unit 119, receives the signal, and outputs the signal to the reception RF unit 102.

  The reception RF unit 102 down-converts the reception signal input from the antenna 101 from a radio frequency to a baseband frequency and outputs it to the control data demodulation unit 103.

  Control data demodulating section 103 demodulates the received signal including feedback control information that is information on the propagation path condition input from reception RF section 102 and outputs the demodulated signal to propagation path information detecting section 104.

  The propagation path information detection unit 104 acquires propagation channel information, which is feedback information such as SINR, delay spread, or maximum Doppler frequency, from the received signal input from the control data demodulation unit 103 and outputs it to the chip interleaver selection unit 105.

  The chip interleaver selection unit 105 selects a pattern for chip interleaving based on the propagation channel information input from the propagation path information detection unit 104. Specifically, the chip interleaver selection unit 105 selects the number of read columns according to the propagation path condition when using a block interleaver. The chip interleaver selection unit 105 selects an interleaver having a smaller number of read columns as the delay spread is larger. Then, the chip interleaver selection unit 105 outputs information on the number of read columns, which is information on the pattern at the time of the selected chip interleaving, to the chip interleave pattern information generation unit 106 and the chip interleave unit 116.

  The chip interleave pattern information generation unit 106 generates signaling information for notifying the communication terminal apparatus of the chip interleave pattern from the pattern information input from the chip interleaver selection unit 105, and outputs the signaling information to the frequency conversion unit 117.

  The information data generation unit 107 generates information data and outputs it to the channel coding unit 108.

  Channel encoding section 108 generates encoded data by performing error correction encoding on the information data input from information data generating section 107, and outputs the generated encoded data to bit interleaving section 109.

  The bit interleaving unit 109 rearranges the encoded data input from the channel encoding unit 108 for each bit and outputs the rearranged data to the data modulation unit 110.

  Data modulation section 110 modulates the encoded data input from bit interleaving section 109 to generate symbol data, and outputs the generated symbol data to serial / parallel conversion section 111. Here, the symbol data is data before being multiplied by the spreading code.

  The serial / parallel conversion unit 111 converts the symbol data input from the data modulation unit 110 from a serial data sequence to a parallel data sequence, and outputs the converted data to the symbol duplication units 112-1 to 112-n.

  Symbol duplication units 112-1 to 112-n duplicate the same number of symbol data input from serial-parallel conversion unit 111 as spreading factor SF and output the same to multipliers 114-1-1 to 114 -n-k.

  Spreading code generating section 113 generates a spreading code unique to the communication terminal apparatus, and outputs the generated spreading code to multipliers 114-1-1-1 to 114-nk.

  Multipliers 114-1-1 to 114 -n-k multiply the symbol data input from symbol duplication units 112-1 to 112-n and the spreading code input from spreading code generation unit 113 to perform spreading processing. Chip data is generated, and the generated chip data is output to the signal synthesis unit 115. Here, the chip data is data after being multiplied by the spreading code.

  The signal synthesizer 115 code-multiplexes or user-multiplexes the chip data input from the multipliers 114-1-1-1 to 114-nk between the chips to generate a plurality of code-multiplexed symbol data in units of chips. The generated code-multiplexed symbol data in units of chips is output to the chip interleave unit 116.

  The chip interleaving unit 116 rearranges the chip data input from the signal synthesis unit 115 for each chip based on the pattern interleaving information input from the chip interleaver selection unit 105. Then, the chip interleaving unit 116 outputs the rearranged chip data to the frequency conversion unit 117.

  The frequency conversion unit 117 performs, for example, inverse fast Fourier transform (IFFT) on the chip-multiplexed chip data input from the chip interleaving unit 116, and each of the code-multiplexed chip data is associated with each chip data. An MC-CDMA signal is generated by arranging the subcarriers. At this time, the frequency conversion unit 117 generates an MC-CDMA signal including the signaling information input from the chip interleave pattern information generation unit 106. Then, the frequency conversion unit 117 outputs the generated MC-CDMA signal to the guard interval insertion unit 118. Here, the MC-CDMA signal is a CDMA signal obtained by spreading symbol data in the frequency domain.

  The guard interval insertion unit 118 inserts a guard interval into the MC-CDMA signal input from the frequency conversion unit 117 and outputs the signal to the transmission RF unit 119.

  The transmission RF unit 119 up-converts the MC-CDMA signal input from the guard interval insertion unit 118 from the baseband frequency to the radio frequency and outputs it to the antenna 101.

  Next, the configuration of communication terminal apparatus 200 that is a communication partner of communication apparatus 100 will be described with reference to FIG. FIG. 2 is a block diagram showing a configuration of communication terminal apparatus 200.

  The antenna 201 transmits the transmission signal input from the transmission RF unit 220, receives the signal, and outputs it to the reception RF unit 202.

  The reception RF unit 202 down-converts the reception data input from the antenna 201 from the radio frequency to the baseband frequency, and outputs it to the control data demodulation unit 203 and the guard interval removal unit 205.

  Control data demodulating section 203 demodulates control data including signaling information notifying the chip interleaving pattern input from reception RF section 202 and outputs the demodulated control data to interleave pattern detecting section 204.

  Interleaving pattern detection section 204 detects a chip interleaving pattern from the signaling information included in the demodulated data input from control data demodulation section 203 and outputs the detected pattern to chip deinterleaving section 210.

  The guard interval removal unit 205 removes the guard interval from the reception data input from the reception RF unit 202 and outputs the data to the frequency conversion unit 206.

  The frequency conversion unit 206, for example, performs fast Fourier transform (FFT) on the received data input from the guard interval removal unit 205 to decompose each subcarrier component into channel estimation unit 207 and multipliers 209-1-1 to 209-. Output to nk.

  The channel estimation unit 207 performs channel estimation from a known signal included in the reception data input from the frequency conversion unit 206. Channel estimation section 207 then outputs the estimation result to subcarrier weight generation section 208.

  The subcarrier weight generation unit 208 sets a weighting factor for compensating for channel fluctuation based on the estimation result input from the channel estimation unit 207, and uses the set weighting factor by the multipliers 209-1-1 to 209-n−. output to k.

  Multipliers 209-1-1 to 209 -n-k multiply the received data input from frequency conversion section 206 by the weight coefficient input from subcarrier weight generation section 208 and output the result to chip deinterleave section 210.

  The chip deinterleave unit 210 rearranges the received data input from the multipliers 209-1-1 to 209 -n-k by performing chip deinterleaving based on the chip interleave pattern information input from the interleave pattern detection unit 204. . The data rearranged in this way is returned to the array before rearrangement by the chip interleave unit 116 of the communication apparatus 100. Then, chip deinterleaving section 210 outputs the rearranged received data to multipliers 212-1-1-1 to 212-nk.

  Spreading code generating section 211 generates a spreading code unique to the communication terminal apparatus, and outputs the generated spreading code to multipliers 212-1-1-1 to 212-nk. The spreading code generated by the spreading code generation unit 211 generates the same spreading code as the spreading code obtained by spreading the signal addressed to itself in the communication device 100. Then, spreading code generation section 211 outputs the generated spreading code to multipliers 212-1-1-1 to 212-nk.

  Multipliers 212-1-1 to 212 -n-k multiply the received data input from chip deinterleaver 210 by the spreading code input from spreading code generator 211 to generate symbol combining units 213-1 to 213 -n. Output to.

  Symbol combination sections 213-1 to 213-n perform symbol combination, that is, despread, on the received data input from multipliers 212-1-1-1 to 212-nk, and output the result to parallel-serial conversion section 214.

  The parallel-serial conversion unit 214 converts the reception data input from the symbol synthesis units 213-1 to 213-n from a parallel data sequence to a serial data sequence and outputs the data to the data demodulation unit 215.

  The data demodulator 215 demodulates the received data input from the parallel / serial converter 214 to generate demodulated data, and outputs the generated demodulated data to the bit deinterleaver 216.

  The bit deinterleaver 216 rearranges the received data input from the data demodulator 215 by bit deinterleaving. The data rearranged in this way is returned to the arrangement before being rearranged by the bit interleave unit 109 of the communication apparatus 100. Bit deinterleaving section 216 then outputs the rearranged received data to channel decoding section 217.

  Channel decoding section 217 decodes the reception data input from bit deinterleaving section 216 to generate decoded data, and outputs the generated decoded data to information data demodulation section 218.

  The information data demodulator 218 makes a hard decision on the decoded data input from the channel decoder 217 to generate demodulated data, and outputs the generated demodulated data to the feedback information generator 219.

  The feedback information generation unit 219 generates propagation channel state measurement results such as SINR, delay spread or maximum Doppler frequency, and feedback information such as ACK / NACK from the demodulated data input from the information data demodulation unit 218, and transmits the transmission RF. Output to the unit 220.

  The transmission RF unit 220 up-converts the transmission signal including the feedback information input from the feedback information generation unit 219 from the baseband frequency to the radio frequency and outputs it to the antenna 201.

  Next, the operation of the communication device 100 will be described. The antenna 101 receives a signal including feedback information from the communication terminal apparatus 200, the control data demodulator 103 demodulates the received signal to generate demodulated data, and the propagation path information detector 104 receives the propagation channel information from the demodulated data. The chip interleaver selecting unit 105 selects a pattern for chip interleaving based on the propagation channel information.

  For example, the chip interleaver selection unit 105 stores rearrangement information that associates the delay spread as shown in FIG. 3 with the number of read columns as the chip interleave pattern, and is detected by the propagation path information detection unit 104. Using the delayed spread information, the number of read columns of the block interleaver is selected by referring to the rearrangement information. That is, when the delay spread τ is greater than 0 and less than a (0 <a), a block interleaver with the number of read columns R0 is selected, and the delay spread τ is greater than a and less than b (a <b). In this case, a block interleaver with the number of read columns R1 (0 <R1) is selected, and when the delay spread τ is greater than or equal to b and less than c (b <c), the block with the number of read columns R2 (R1> R2) When an interleaver is selected and the delay spread τ is greater than or equal to c, a block interleaver with the number of read columns R3 (R2> R3) is selected. FIG. 4A shows a block interleaver with a read column number R1, FIG. 4B shows a block interleaver with a read column number R2, and FIG. 4C shows a block interleaver with a read column number R3. The number of read columns R0 is a case where no block interleaver is used, that is, a case where chip interleaving is not performed. The number of read columns R1 is composed of columns of R1 and rows of RW / R1 (RW / R1 is a natural number greater than 0). In this case, chip interleaving is performed using a block interleaver, and the number of read columns R2 is determined by using a block interleaver consisting of R2 columns and RW / R2 (RW / R2 is a natural number greater than RW / R1). The number of read columns R3 is a case where chip interleaving is performed using a block interleaver composed of columns of R3 and rows of RW / R3 (RW / R3 is a natural number larger than RW / R2).

  Next, communication apparatus 100 transmits, as signaling information, pattern information for chip interleaving selected by chip interleaver selection section 105.

  On the other hand, the information data generation unit 107 generates information data, the channel encoding unit 108 generates encoded data by error correction encoding the information data, and the bit interleaving unit 109 rearranges the encoded data bit by bit, The data modulation unit 110 modulates the encoded data to generate symbol data, and the serial / parallel conversion unit 111 converts the modulation data from a serial data sequence to a parallel data sequence. Further, the symbol duplicating units 112-1 to 112-n duplicate the symbol data by the same number as the spreading factor SF, the spreading code generating unit 113 generates a spreading code unique to the communication terminal device, and a multiplier 114-1-1. ... 114-n-k multiply the symbol data and the spreading code to generate chip data, and the signal synthesizer 115 code-multiplexes or user-multiplexes the chip data between the chips and performs code multiplexing in units of a plurality of chips. Generate chip data.

  Next, the chip interleaving unit 116 rearranges the chip data for each chip on the basis of the pattern information at the time of chip interleaving. For example, when the chip interleaver selection unit 105 selects a 4 × 4 block interleaver based on the measured delay spread information, as shown in FIG. The chip-multiplexed chip data of each chip is written by four chips in the direction of the writing direction # 501 for each row. By writing in the writing direction # 501, the first, second, third, fourth chips are written in the first row, and the fifth, sixth, seventh, and eighth chips are written in the second row. The ninth, tenth, eleventh and twelfth chips are written in the third row, and the thirteenth, fourteenth, fifteenth and sixteenth chips are written in the fourth row.

  Next, the chip interleaving unit 116 reads the code-multiplexed chip data of each chip written in the reading direction # 502 for each column and arranges them in the reading order. As a result of reading in this way, the code-multiplexed chip data of the chips arranged in the order of numbers from the 1st to the 16th are the first, fifth, ninth, thirteenth, second, sixth, tenth, The fourteenth, third, seventh, eleventh, fifteenth, fourth, eighth, twelfth and sixteenth chips are rearranged in this order.

  Next, the frequency conversion unit 117 performs, for example, inverse fast Fourier transform on the chip-multiplexed chip data input from the chip interleaving unit 116, and each of the code-multiplexed chip data is associated with each chip data. The MC-CDMA signal is generated by arranging the subcarriers, the guard interval inserting unit 118 inserts the guard interval into the MC-CDMA signal, and the transmission RF unit 119 changes the MC-CDMA signal from the baseband frequency to the radio frequency. After up-conversion, the antenna 101 transmits an MC-CDMA signal.

Here, the error rate characteristic or throughput in the MC-CDMA signal is affected by three parameters: normalized code number (normalized code number = code multiplexing number Cmux / spreading rate SF), data modulation scheme, and frequency correlation value ρ _ΔF. Receive. In the first embodiment, receiving characteristics are improved by paying attention to the frequency correlation value. That is, the frequency correlation value and the delay spread have a one-to-one correspondence, and the correlation of the frequency components separated by the frequency interval ΔF can be expressed as in equation (1).

From equation (1), if the frequency interval between adjacent subcarriers is Δf, the frequency correlation ρ _nΔf of subcarriers separated by n subcarriers can be expressed as equation (2).

The diversity effect at the time of MC-CDMA despreading increases as the inter-subcarrier correlation value in the symbol decreases, and the reception characteristics are improved. On the other hand, the orthogonality between code-multiplexed or user-multiplexed codes collapses as the intersymbol correlation value decreases, and as a result, the reception characteristics deteriorate. That is, since the improvement due to the diversity effect and the degradation due to inter-code interference are in a trade-off relationship, there exists a frequency correlation value that minimizes the error rate. This value differs depending on the normalization code multiplexing number and the data modulation multi-level number. Here, assuming that the normalized delay spread obtained by normalizing the delay spread by the subcarrier bandwidth SFΔf corresponding to the spreading factor is SFΔfτ _rms , the frequency correlation value ρ _SFΔf can be expressed as shown in Equation (3).

From equation (3), the frequency correlation value ρ _opt that provides the best reception characteristics can be obtained by adaptively changing the normalized delay spread SFΔfτ _rms . The spreading factor can be easily realized by variable spreading factor control by OVSF (Orthogonal Variable Spreading Factor). With respect to Δf, MC-CDMA symbol length 1 / Δf may be changed, but this is very difficult. Since τ _rms is a propagation path parameter, it cannot be controlled on the transmitting side and the receiving side, but it is possible to control the delay spread equivalently by applying frequency direction chip interleaving. For example, as a chip interleaver, consider a 4 × 4 block interleaver as shown in FIG. When four chips are written in the row direction and four chips are read in the column direction, chips arranged in adjacent subcarriers are arranged apart by four subcarriers in the propagation channel. This corresponds to an equivalent quadruple delay spread.

  As described above, according to the first embodiment, the fading channel in the symbol data can be optimally randomized by selecting the optimal interleaving method based on the propagation path environment such as delay spread. Even if channel gain drops due to consecutive subcarriers, randomization can be performed optimally, and reception characteristics can be improved.

(Embodiment 2)
FIG. 6 is a block diagram showing a configuration of communication apparatus 600 according to Embodiment 2 of the present invention.

  As shown in FIG. 6, communication apparatus 600 according to Embodiment 2 adds chip interleaver control section 601 except for chip interleaver selection section 105 in communication apparatus 100 according to Embodiment 1 shown in FIG. Instead of the chip interleave unit 116, chip interleave units 602-1 to 602-n are provided. In FIG. 6, parts having the same configuration as in FIG.

  The propagation path information detection unit 104 acquires propagation channel information such as SINR, delay spread, or maximum Doppler frequency from the received signal input from the control data demodulation unit 103 and outputs it to the chip interleaver control unit 601.

  The chip interleaver control unit 601 selects an interleave pattern for chip interleaving based on the propagation channel information input from the propagation path information detection unit 104. Specifically, the chip interleaver control unit 601 selects an interleave length according to the propagation path condition. The chip interleaver control unit 601 selects an interleaver having a smaller interleave length as the delay spread is larger. Then, the chip interleaver control unit 601 outputs the selected pattern interleaving pattern information to the chip interleave pattern information generation unit 106 and the chip interleave units 602-1 to 602-n.

  The chip interleave pattern information generation unit 106 generates signaling information for notifying the communication terminal device of the chip interleave pattern from the pattern information input from the chip interleaver control unit 601, and outputs the signaling information to the frequency conversion unit 117.

  The signal synthesizer 115 code-multiplexes or user-multiplexes the chip data input from the multipliers 114-1-1-1 to 114-nk between the chips to generate a plurality of chip-multiplexed chip data. The generated chip data, which is code-multiplexed in units of a plurality of chips, is output to the chip interleaving units 602-1 to 602-n.

  The chip interleaving units 602-1 to 602-n rearrange the chip data input from the signal synthesis unit 115 for each chip based on the pattern information at the time of chip interleaving input from the chip interleaver control unit 601. Then, the chip interleaving units 602-1 to 602-n output the rearranged chip data to the frequency conversion unit 117.

  The frequency conversion unit 117 performs, for example, inverse Fourier transform on the chip-multiplexed chip data input from the chip interleaving units 602-1 to 602-n, and supports each symbol data that has been code-multiplexed. An MC-CDMA signal is generated by being arranged on each subcarrier. At this time, the frequency conversion unit 117 generates an MC-CDMA signal including the signaling information input from the chip interleave pattern information generation unit 106. Then, the frequency conversion unit 117 outputs the generated MC-CDMA signal to the guard interval insertion unit 118.

  Next, the configuration of communication terminal apparatus 700 that is the communication partner of communication apparatus 600 will be described using FIG. FIG. 7 is a block diagram showing a configuration of communication terminal apparatus 700.

  As shown in FIG. 7, communication terminal apparatus 700 according to Embodiment 2 is replaced with chip deinterleaving section 701-in place of chip deinterleaving section 210 in communication terminal apparatus 200 according to Embodiment 1 shown in FIG. 1-701-n. In FIG. 7, parts having the same configuration as in FIG.

  Interleaving pattern detection section 204 detects a chip interleaving pattern from the signaling information included in the demodulated data input from control data demodulation section 203 and outputs the detected pattern to chip deinterleaving sections 701-1 to 701-n.

  Multipliers 209-1-1 to 209 -n-k multiply the reception data input from frequency converter 206 by the weighting factor input from subcarrier weight generator 208, and chip deinterleavers 701-1 to 701-. output to n.

  The chip deinterleave units 701-1 to 701 -n receive the received data input from the multipliers 209-1-1 to 209 -n-k from the chip interleave pattern information input from the interleave pattern detection unit 204. Sort by interleaving. The data rearranged in this way is returned to the array before the rearrangement by the chip interleaving units 602-1 to 602-n of the communication device 600. Then, chip deinterleaving sections 701-1 to 701-n output rearranged received data to multipliers 212-1-1-1 to 212-nk.

  Multipliers 212-1-1 to 212 -n-k multiply the received data input from chip deinterleave units 701-1 to 701 -n by the spreading code input from spreading code generator 211 to generate symbol combining unit 213. -1 to 213-n.

  Next, the operation of the communication device 600 will be described. Antenna 101 receives a signal including feedback information from communication terminal apparatus 700, control data demodulation section 103 demodulates the received signal to generate demodulated data, and propagation path information detection section 104 receives propagation channel information from the demodulated data. Then, the chip interleaver control unit 601 selects a pattern for chip interleaving based on the propagation channel information.

  For example, the chip interleaver control unit 601 stores rearrangement information that associates the delay spread as shown in FIG. 8 with the interleave length as the chip interleave pattern, and is detected by the propagation path information detection unit 104. By using the information on the delay spread, the interleaving length of the interleaver is selected by referring to the sorting information. That is, when the delay spread τ is greater than 0 and less than d1, an interleaver with an interleave length L0 is selected, and when the delay spread τ is greater than or equal to d1 and less than d2, the interleave length L1 (0 <L1) is selected. When an interleaver is selected and the delay spread τ is greater than or equal to d (n−1) and less than dn (n is an arbitrary natural number), the interleave length L (n−1) (L1 <L (n−1)) When the delay spread τ is dn or more, an interleaver with an interleave length Ln (Ln−1 <Ln) is selected. Here, the interleave length is the length of the interleaver, the minimum value of the interleave length is the same value as the spreading factor SF, and the maximum value of the interleave length is the same value as the number of subcarriers.

  Next, communication apparatus 600 transmits, as signaling information, pattern information for chip interleaving selected by chip interleaver selection section 601.

  On the other hand, the information data generation unit 107 generates information data, the channel encoding unit 108 generates encoded data by error correction encoding the information data, and the bit interleaving unit 109 rearranges the encoded data bit by bit, The data modulation unit 110 modulates the encoded data to generate symbol data, and the serial / parallel conversion unit 111 converts the symbol data from a serial data sequence to a parallel data sequence. Further, the symbol duplicating units 112-1 to 112-n duplicate the symbol data by the same number as the spreading factor SF, the spreading code generating unit 113 generates a spreading code unique to the communication terminal device, and a multiplier 114-1-1. ... 114-n-k multiply the symbol data and the spreading code to generate chip data, and the signal synthesizer 115 code-multiplexes or user-multiplexes the chip data between the chips and performs code multiplexing in units of a plurality of chips. Generate chip data.

  Next, the chip interleaving units 602-1 to 602-n rearrange the chip data for each chip based on the pattern information at the time of chip interleaving.

  Next, the frequency conversion unit 117 performs, for example, inverse fast Fourier transform (IFFT) on the plurality of chip-unit code-multiplexed chip data input from the chip interleaving units 602-1 to 602-n, thereby performing code multiplexing. Each chip data is arranged in each corresponding subcarrier to generate an MC-CDMA signal, the guard interval insertion unit 118 inserts a guard interval into the MC-CDMA signal, and the transmission RF unit 119 receives the MC-CDMA The antenna 101 transmits the MC-CDMA signal by up-converting the signal from the baseband frequency to the radio frequency.

  Thus, according to the second embodiment, the fading channel in the symbol data can be optimally randomized by selecting the optimal interleaving method based on the propagation path environment such as delay spread. Even if channel gain drops due to consecutive subcarriers, randomization can be performed optimally, and reception characteristics can be improved.

(Embodiment 3)
FIG. 9 is a block diagram showing a configuration of communication apparatus 900 according to Embodiment 3 of the present invention.

  As shown in FIG. 9, communication apparatus 900 according to the third embodiment has a chip interleaving unit 901 in place of chip interleaving section 116 in communication apparatus 100 according to the first embodiment shown in FIG. 1. 9, parts having the same configuration as in FIG. 1 are denoted by the same reference numerals and description thereof is omitted.

  Information data generator 107, channel encoder 108, bit interleaver 109, data modulator 110, serial-parallel converter 111, symbol duplicators 112-1 to 112-n, spreading code generator 113, multiplier 114-1 −1 to 114-n−k and the chip interleaving unit 901 constitute signal processing units 902-1 to 902-u. The signal processing units 902-1 to 902-u are provided in the same number as the number of communication terminal devices (users), and process signals to be transmitted to each communication terminal device.

  The chip interleaver selection unit 105 selects a pattern for chip interleaving unique to each communication terminal apparatus based on the propagation channel information input from the propagation path information detection unit 104. Specifically, the chip interleaver selection unit 105 selects the number of read columns according to the propagation path condition when using a block interleaver. Then, the chip interleaver selecting unit 105 outputs the selected pattern interleaving pattern information to the chip interleave pattern information generating unit 106 and the chip interleaving unit 901. The pattern selected by the chip interleaver selection unit 105 is a pattern that is different for each communication terminal device.

  Multipliers 114-1-1 to 114 -n-k multiply the symbol data input from symbol duplication units 112-1 to 112-n and the spreading code input from spreading code generation unit 113 to perform spreading processing. Chip data is generated, and the generated chip data is output to the chip interleave unit 901.

  The chip interleaving unit 901 rearranges the chip data input from the multipliers 114-1-1 to 114 -nk for each chip based on the pattern interleaving information input from the chip interleaver selection unit 105. . Then, the chip interleave unit 901 outputs the rearranged symbol data to the signal synthesis unit 115.

  The signal synthesizer 115 code-multiplexes or user-multiplexes the chip data of each communication terminal device input from the chip interleave unit 901 between the chips to generate a plurality of code-multiplexed chip data in units of chips. A plurality of chip code-multiplexed chip data is output to the frequency converter 117. Note that the configuration of the communication terminal device that is the communication partner of the communication device 900 is the same as that shown in FIG.

  FIG. 10 is a diagram illustrating a propagation channel state. The base station 1001 includes a communication device 900, and each communication terminal device 1002, 1003, and 1004 that communicates with the base station 1001 in the cell # 1005 has the same configuration as the communication terminal device 200 of FIG. Of the three communication terminal apparatuses 1002, 1003, and 1004, the communication terminal apparatus 1002 communicates with the base station 1001 at a position farthest from the base station 1001, and the communication terminal apparatus 1003 communicates with the base station 1001. The communication terminal apparatus 1004 performs communication at a position closer to the base station 1001 than the communication terminal apparatus 1002 and further away from the base station 1001 than the communication terminal apparatus 1003. is there.

  The delay spread detected by the base station 1001 is the largest in the delay spread # 1006 of the communication terminal apparatus 1002, the smallest in the delay spread # 1007 of the communication terminal apparatus 1003, and the delay spread # 1008 of the communication terminal apparatus 1004 is the communication terminal apparatus 1002. Is larger than the delay spread # 1007 of the communication terminal apparatus 1003. The chip interleaver selection unit 105 selects an interleaver having a smaller number of read columns as the delay spread is larger. Therefore, in the case of FIG. 10, the number of read columns of the interleaver selected by the chip interleaver selection unit 105 of the communication terminal device 1002 is the smallest, and the number of read columns of the interleaver selected by the chip interleaver selection unit 105 of the communication terminal device 1003 is the largest. .

  As described above, according to the third embodiment, in addition to the effects of the first embodiment, the chip data is rearranged with a different chip interleave pattern for each communication terminal device of each user. The optimum chip interleave pattern can be selected according to the different delay spread detection results, and the reception performance for all communication terminal apparatuses can be improved with high accuracy.

(Embodiment 4)
FIG. 11 is a block diagram showing a configuration of communication apparatus 1100 according to Embodiment 4 of the present invention.

  As shown in FIG. 11, communication apparatus 1100 according to Embodiment 4 adds radio resource management section 1101 to communication apparatus 100 according to Embodiment 1 shown in FIG. In FIG. 11, parts having the same configuration as in FIG.

  The propagation path information detection unit 104 acquires propagation channel information such as SINR, delay spread, or maximum Doppler frequency from the received signal input from the control data demodulation unit 103 and outputs it to the chip interleaver selection unit 105 and the radio resource management unit 1101. To do.

  The radio resource management unit 1101 manages transmission parameters such as spreading factor, code multiplexing number, and MCS level of each user. That is, the radio resource management unit 1101 selects the transmission parameters of the modulation multi-value number, spreading factor, and normalized code number based on the propagation channel information input from the propagation path information detection unit 104. Then, the radio resource management unit 1101 instructs the data modulation unit 110 to perform modulation with the selected modulation multi-value number, and performs spreading processing on the spreading code generation unit 113 with the selected spreading factor. And instructing the signal synthesizer 115 to code-multiplex with the number of codes that is the selected number of normalized codes.

  Based on an instruction from radio resource management section 1101, data modulation section 110 modulates the encoded data input from bit interleaving section 109 to generate symbol data, and outputs the generated symbol data to serial / parallel conversion section 111. .

  Spreading code generating section 113 generates a spreading code unique to the communication terminal apparatus based on an instruction from radio resource management section 1101 and outputs the generated spreading code to multipliers 114-1-1-1 to 114-nk. To do.

  Based on an instruction from the radio resource management unit 1101, the signal synthesis unit 115 performs code multiplexing or user multiplexing of chip data input from the multipliers 114-1-1-1 to 114-nk to a plurality of chips. The unit code-multiplexed chip data is generated, and the generated plurality of chip-unit code-multiplexed chip data is output to the chip interleave unit 116. Note that the configuration of the communication terminal device that is the communication partner of the communication device 1100 is the same as that shown in FIG.

  Next, the operation of the communication device 1100 will be described. The antenna 101 receives a signal including feedback information from the communication terminal device, the control data demodulator 103 demodulates the received signal to generate demodulated data, and the propagation path information detector 104 acquires propagation channel information from the demodulated data. Then, the radio resource management unit 1101 selects a transmission parameter using the propagation channel information.

  For example, as shown in FIG. 12, the radio resource management unit 1101 uses a combination # 1201 in which the modulation scheme is QPSK, the spreading factor SF is 16, and the number of normalized codes is 8/16, the modulation scheme is QPSK, and the spreading factor SF. Is 16 and the number of normalized codes is 16/16, the modulation method is 16QAM, the spreading factor SF is 16 and the number of normalized codes is 8/16, the combination # 1203, and the modulation method is 16QAM, A combination of four transmission parameters of a combination # 1204 in which the spreading factor SF is 16 and the number of normalized codes is 16/16 is stored. In this case, as shown in FIG. 13, the relationship between the delay spread and the error rate characteristic of each combination has the relationship # 1301 between the delay spread and the error rate characteristic in the case of the combination # 1201, and in the case of the combination # 1202. It has a relationship # 1302 between the delay spread and the error rate characteristic. In the case of the combination # 1203, it has a relationship # 1303 between the delay spread and the error rate characteristic, and in the case of the combination # 1204, the delay spread and the error rate characteristic. Relationship # 1304. In the relationship # 1301 between the delay spread and the error rate characteristic, the optimum value for which the error rate characteristic is most improved is the delay spread P1, and in the relation # 1302 between the delay spread and the error rate characteristic, the optimum is obtained that the error rate characteristic is most improved. The value is the delay spread P2, and the optimum value for which the error rate characteristic is most improved in the relationship # 1303 between the delay spread and the error rate characteristic is the delay spread P3, and is the most in the relationship # 1304 between the delay spread and the error rate characteristic. The optimum value for improving the error rate characteristic is the delay spread P4.

  In the case of having such a relationship, the radio resource management unit 1101 detects a combination of transmission parameters in which the delay spread detected by the propagation path information detection unit 104 becomes an optimum value or is detected by the propagation path information detection unit 104. The combination of the transmission parameter having the optimum value closest to the delay spread is selected, and the transmission data is instructed to be processed with the selected transmission parameter. Since the subsequent operation of communication apparatus 1100 is the same as that in Embodiment 1, the description thereof is omitted.

  As described above, according to the fourth embodiment, in addition to the effect of the first embodiment, the transmission parameter is changed according to the propagation path condition, so that the reception performance can be reliably improved.

(Embodiment 5)
FIG. 14 is a block diagram showing a configuration of communication apparatus 1400 according to Embodiment 5 of the present invention.

  As shown in FIG. 14, communication apparatus 1400 according to the fifth embodiment is the same as communication apparatus 100 according to the first embodiment shown in FIG. 1 except for chip interleaver selection section 105 and radio resource management section 1401 and chip interleaver. A control unit 1402 is added, and chip interleaving units 1403-1 to 1403-n are provided instead of the chip interleaving unit 116. 14, parts having the same configuration as in FIG. 1 are denoted by the same reference numerals and description thereof is omitted.

  The propagation path information detection unit 104 acquires propagation channel information such as SINR, delay spread, or maximum Doppler frequency from the received signal input from the control data demodulation unit 103 and outputs it to the chip interleaver control unit 1402 and the radio resource management unit 1401. To do.

  The radio resource management unit 1401 manages transmission parameters such as spreading factor, code multiplexing number, and MCS level of each user. That is, the radio resource management unit 1401 selects the transmission parameters of the modulation multilevel number, spreading factor, and normalized code number based on the propagation channel information input from the propagation path information detection unit 104. Then, the radio resource management unit 1401 instructs the data modulation unit 110 to perform modulation with the selected modulation multi-value number, and performs spreading processing on the spreading code generation unit 113 with the selected spreading factor. And instructing the signal synthesizer 115 to code-multiplex with the number of codes that is the selected number of normalized codes.

  The chip interleaver control unit 1402 selects an interleaving pattern for chip interleaving based on the propagation channel information input from the propagation path information detection unit 104. Specifically, when using a block interleaver, chip interleaver control section 1402 selects an interleave length according to the propagation path condition. The chip interleaver control unit 1402 selects an interleaver having a smaller interleave length as the delay spread is larger. Then, chip interleaver control section 1402 outputs the selected pattern interleaving pattern information to chip interleave pattern information generating section 106 and chip interleave sections 1403-1 to 1403-n.

  The chip interleave pattern information generation unit 106 generates signaling information for notifying the communication terminal device of the chip interleave pattern from the pattern information input from the chip interleaver control unit 1402 and outputs the signaling information to the frequency conversion unit 117.

  Based on an instruction from radio resource management section 1401, data modulation section 110 modulates the encoded data input from bit interleaving section 109 to generate symbol data, and outputs the generated symbol data to serial / parallel conversion section 111. .

  Spreading code generating section 113 generates a spreading code unique to the communication terminal apparatus based on an instruction from radio resource managing section 1401, and outputs the generated spreading code to multipliers 114-1-1-1 to 114-nk. To do.

  Based on an instruction from the radio resource management unit 1401, the signal synthesis unit 115 performs code multiplexing or user multiplexing of chip data input from the multipliers 114-1-1-1 to 114-nk to a plurality of chips. The unit code-multiplexed chip data is generated, and the generated plurality of chip-unit code-multiplexed chip data is output to the chip interleave units 1403-1 to 1403-n. Note that the configuration of the communication terminal device, which is the communication partner of the communication device 1400, is the same as that in FIG.

  The chip interleaving units 1403-1 to 1403-n rearrange the chip data input from the signal synthesis unit 115 for each chip based on the pattern interleaving information input from the chip interleaver control unit 1402. Then, the chip interleave units 1403-1 to 1403-n output the rearranged chip data to the frequency converter 117.

  The frequency conversion unit 117 performs inverse fast Fourier transform, for example, on the chip-multiplexed chip data in units of a plurality of chips input from the chip interleaving units 1403-1 to 1403-n, and converts each of the code-multiplexed chip data. An MC-CDMA signal is generated by arranging each corresponding subcarrier. At this time, the frequency conversion unit 117 generates an MC-CDMA signal including the signaling information input from the chip interleave pattern information generation unit 106. Then, the frequency conversion unit 117 outputs the generated MC-CDMA signal to the guard interval insertion unit 118. Note that the communication terminal device that is the communication partner of the communication device 1400 has the same configuration as that shown in FIG.

  As described above, according to the fifth embodiment, in addition to the effect of the first embodiment, the transmission parameter is changed according to the propagation path condition, so that the reception performance can be reliably improved.

(Embodiment 6)
FIG. 15 is a block diagram showing a configuration of communication apparatus 1500 according to Embodiment 6 of the present invention.

  As shown in FIG. 15, communication apparatus 1500 according to the sixth embodiment adds radio resource management section 1501 to communication apparatus 100 according to the first embodiment shown in FIG. 1, and replaces chip interleaving section 116. A chip interleave unit 1502 is included. In FIG. 15, parts having the same configuration as in FIG.

  The propagation path information detection unit 104 acquires propagation channel information such as SINR, delay spread, or maximum Doppler frequency from the received signal input from the control data demodulation unit 103 and outputs it to the chip interleaver selection unit 105 and the radio resource management unit 1501. To do.

  The radio resource management unit 1501 manages transmission parameters such as spreading factor, code multiplexing number, and MCS level of each user. That is, the radio resource management unit 1501 selects transmission parameters of the modulation multi-level number, spreading factor, and normalized code number based on the propagation channel information input from the propagation path information detection unit 104. Then, the radio resource management unit 1501 instructs the data modulation unit 110 to perform modulation with the selected modulation multi-value number, and performs a spreading process on the spreading code generation unit 113 with the selected spreading factor. And instructing the signal synthesizer 115 to code-multiplex with the number of codes that is the selected number of normalized codes.

  The chip interleaver selection unit 105 selects a pattern for chip interleaving based on the propagation channel information input from the propagation path information detection unit 104. For example, when a block interleaver is used, the chip interleaver selection unit 105 selects the number of read columns according to the delay spread. At this time, the chip interleaver selection unit 105 selects an interleaver based on the modulation multi-value number, spreading factor, and normalized code number. Then, the chip interleaver selecting unit 105 outputs the selected pattern interleaving pattern information to the chip interleave pattern information generating unit 106 and the chip interleaving unit 1502.

  Data modulation section 110 modulates the encoded data input from bit interleaving section 109 based on an instruction from radio resource management section 1501 to generate symbol data, and outputs the generated symbol data to serial / parallel conversion section 111. .

  Spreading code generating section 113 generates a spreading code unique to the communication terminal apparatus based on an instruction from radio resource management section 1501 and outputs the generated spreading code to multipliers 114-1-1-1 to 114-nk. To do.

  Multipliers 114-1-1 to 114 -n-k multiply the symbol data input from symbol duplication units 112-1 to 112-n and the spreading code input from spreading code generation unit 113 to perform spreading processing. Chip data is generated, and the generated chip data is output to the chip interleave unit 1502.

  The chip interleaving unit 1502 rearranges the chip data input from the multipliers 114-1-1 to 114 -nk for each chip based on the pattern interleaving information input from the chip interleaver selection unit 105. . Then, chip interleaving section 1502 outputs the rearranged chip data to signal synthesis section 115.

  The signal synthesis unit 115 code-multiplexes or user-multiplexes the chip data of each communication terminal device input from the chip interleaving unit 1502 between the chips to generate a plurality of code-multiplexed chip data in units of chips. A plurality of chip code-multiplexed chip data is output to the frequency converter 117. The configuration of the communication terminal device that is the communication partner of communication device 1500 is the same as that in FIG.

  As described above, according to the sixth embodiment, in addition to the effects of the first embodiment, the transmission parameter is changed according to the propagation path condition, so that the reception performance can be reliably improved. Further, according to the sixth embodiment, since the chip data is rearranged with a different chip interleave pattern for each communication terminal device of each user, the optimum chip is selected according to the different delay spread measurement results for each communication terminal device. An interleave pattern can be selected, and reception performance for all communication terminal apparatuses can be improved.

  In the first to sixth embodiments, the chip data is arranged in the frequency axis direction by arranging the chip data in each subcarrier. However, the present invention is not limited to this, and the chip data is arranged in the time axis direction. Anyway. In Embodiments 1 to 6, the MC-CDMA signal is transmitted and received. However, the present invention is not limited to this, and an arbitrary signal transmitted using a plurality of subcarriers other than the MC-CDMA signal is transmitted. You may make it transmit / receive. Moreover, the communication apparatus of the said Embodiment 1- Embodiment 6 is applicable to a base station apparatus.

  The communication apparatus, base station apparatus, and transmission method according to the present invention have an effect of improving reception characteristics by selecting an optimal interleaving method, and are useful for transmitting interleaved data.

The block diagram which shows the structure of the communication apparatus which concerns on Embodiment 1 of this invention. The block diagram which shows the structure of the communication terminal device which concerns on Embodiment 1 of this invention. The figure which shows the relationship between the delay spread which concerns on Embodiment 1 of this invention, and the number of read-out columns. The figure which shows the block interleaver which concerns on Embodiment 1 of this invention. The figure which shows the method of interleaving based on Embodiment 1 of this invention. The block diagram which shows the structure of the communication apparatus which concerns on Embodiment 2 of this invention. The block diagram which shows the structure of the communication terminal device which concerns on Embodiment 2 of this invention. The figure which shows the relationship between the delay spread which concerns on Embodiment 2 of this invention, and interleaving length The block diagram which shows the structure of the communication apparatus which concerns on Embodiment 3 of this invention. The figure which shows the state which the base station apparatus and communication terminal device which concern on Embodiment 3 of this invention communicate The block diagram which shows the structure of the communication apparatus which concerns on Embodiment 4 of this invention. The figure which shows the combination of the modulation system which concerns on Embodiment 4 of this invention, a spreading factor, and the number of normalization codes The figure which shows the relationship between the error rate characteristic and delay spread which concern on Embodiment 4 of this invention. The block diagram which shows the structure of the communication apparatus which concerns on Embodiment 5 of this invention. The block diagram which shows the structure of the communication apparatus which concerns on Embodiment 6 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Communication apparatus 103 Control data demodulation part 104 Propagation path information detection part 105 Chip interleaver selection part 106 Chip interleave pattern information generation part 107 Information data generation part 108 Channel encoding part 109 Bit interleaving part 110 Data modulation part 111 Serial parallel conversion part 112 -1 to 112-n Symbol duplicator 113 Spread code generator 114-1-1 to 114-nk multiplier 115 Signal synthesizer 116 Chip interleaver 117 Frequency converter

Claims (10)

Spreading means for generating chip data by spreading the symbol data with a spreading code;
Rearrangement means for rearranging chip data generated by the diffusion means for each chip based on a propagation path environment;
Conversion means for arranging the chip data rearranged for each chip by the rearrangement means on each subcarrier for each chip;
Transmitting means for transmitting chip data arranged on each subcarrier by the converting means;
A communication apparatus comprising: Comprising signal combining means for code-multiplexing chip data generated by spreading processing with a spreading code different for each communication partner in the spreading means,
2. The communication apparatus according to claim 1, wherein the rearranging unit rearranges the chip data code-multiplexed by the signal synthesizing unit for each chip based on a propagation path environment. Comprising signal synthesis means for code-multiplexing the chip data rearranged for each chip by the rearrangement means;
The spreading means generates chip data by spreading the symbol data of each communication partner with a different spreading code for each communication partner,
2. The communication apparatus according to claim 1, wherein the converting means places the chip data code-multiplexed by the signal synthesizing means on each subcarrier for each chip. Propagation path information detecting means for detecting a delay spread indicating the propagation path environment from the received signal,
The rearranger stores rearrangement information that associates a delay spread indicating the propagation path environment with a rearrangement pattern, and uses information on the delay spread detected by the propagation path information detector. 4. The method according to claim 1, wherein the pattern is selected by referring to the rearrangement information, and the chip data is rearranged for each chip in the selected pattern. 5. Communication device. Propagation path information detecting means for detecting a delay spread indicating the propagation path environment from the received signal,
The rearranger stores rearrangement information in which a delay spread indicating the propagation environment and an interleave length are associated with each other, and uses the information on the delay spread detected by the propagation path information detector. The communication according to any one of claims 1 to 4, wherein the interleave length is selected by referring to replacement information, and the chip data is rearranged for each chip by the selected interleave length. apparatus.   Stores transmission parameter setting information associating the combination of the modulation multi-value number, the number of normalized codes and the spreading factor with the optimum value of the delay spread having an error rate characteristic equal to or higher than a predetermined level, and detects the propagation path information. Radio resource management instructing transmission data to be processed with the number of modulation multi-values, the number of normalized codes, and the spreading factor selected by referring to the transmission parameter setting information using the delay spread detected by the means The communication apparatus according to claim 2, further comprising a unit.   A base station apparatus comprising the communication apparatus according to claim 1. A step of spreading the symbol data with a spreading code to generate chip data;
Rearranging the generated chip data for each chip based on the propagation path environment;
Placing chip data rearranged for each chip on each subcarrier for each chip;
Transmitting chip data arranged on each subcarrier;
The transmission method characterized by comprising. A step of code-multiplexing chip data generated by spreading processing with a spreading code different for each communication partner;
9. The transmission method according to claim 8, wherein the code-multiplexed chip data is rearranged for each chip based on a propagation path environment. Comprising the step of code-multiplexing the chip data rearranged for each chip,
Spreading the symbol data of each communication partner with a different spreading code for each communication partner to generate chip data,
9. The transmission method according to claim 8, wherein the code-multiplexed chip data is arranged on each subcarrier for each chip.

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