JP2003309497A - Receiver, transmitter, base station device using the sames and mobile station device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve receiving quality by eliminating line distortion with an equalizer and performing error correction that reduces an error rate at the same time. <P>SOLUTION: A signal received by a receiving antenna 504 is inputted to an UDMV 505 through a detector, distortion compensation for multipath fading and error correction by Viterbi decoding are performed to acquire demodulated data 506. The UDMV 505 is composed of a demodulator obtained by blending an MLSE and a Viterbi decoder to perform processing for obtaining demodulated data, which has been performed by two steps such as 'equalization' and 'error correction' in the conventional manner, with a single step. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a receiver for compensating for distortion due to multipath fading and error correction, and a transmitter for transmitting data to this receiver.

[0002]

2. Description of the Related Art In the field of mobile communication, it is essential to overcome multipath fading and improve transmission quality. It is known that an equalizer is effective for multipath fading, and an error correction code, especially a method of decoding a convolutional code with a soft-decision Viterbi decoder is effective for improving transmission quality. .

A conventional data transmission apparatus is provided with an equalizer for compensating distortion due to multipath fading in a receiving system and a Viterbi decoder for error correction, and the equalizer and the Viterbi decoder are independent. Is working.

FIG. 12 is a block diagram of a conventional data transmission apparatus for independently operating an equalizer and a Viterbi decoder. On the transmission side, transmission data 1 is encoded by convolutional encoder 2, modulated by modulator 3 and transmitted from transmission antenna 4.
On the receiving side, the received signal received by the receiving antenna 5 is passed to the equalizer 6, and the output of the equalizer 6 is decoded by the Viterbi decoder 7 to obtain demodulated data 8. The equalizer 6 compensates for distortion due to multipath fading that occurs on the line, and is equivalent to MLSE (Maximum Likelihood Sequence Es).
timator) or DFE (Decision Feedback Equalize)
r) etc. are used. In particular, it is known that MLSE can realize almost optimum characteristics even in a mobile radio channel in which fading fluctuation is severe.

MLSE using the line model shown in FIG.
The operation principle of the shape equalizer 6 will be described.

The line model shown in the figure is a model of multipath fading due to the path of (N + 1) waves. In this line model, the transmission signal 100 has delay units 101-0 to 101-0.
Rayleigh fading adder 1 delayed by 101-N
02-0 to 102-N undergoes fading fluctuation, and the attenuators 103-0 to 103-N attenuate the fading fluctuations.
It is added at 4 and becomes the received signal 105.

The delay devices 101-0 to 101-N represent delays due to various path lengths, and the Rayleigh fading adders 102-0 to 102-N perform Rayleigh fading independently for each path. It represents.
The transmission signal 100 undergoes random phase fluctuations and level fluctuations according to the Rayleigh distribution due to the delayers and the Rayleigh fading adders.

The attenuators 103-0 to 103-N represent the attenuation independently applied to each path. Since the transmission signal and the reception signal are composed of a quadrature component and an in-phase component in the baseband and can be considered as a complex number having a real part and an imaginary part, each part in FIG. 13 is a complex number. Therefore, the model when finally combined at the receiving antenna end is also the complex adder 104.

FIG. 14 shows a rewriting of the line model shown in FIG. 13 as a model closer to a digital filter. The transmission signal 200 has delay devices 201-0 to 201-2.
01- (N-1), and the complex gain adder 202-
Complex adder 2 with complex gain added from 0 to 202-N
The received signal 204 is combined in 03. The complex gain adders 202-0 to 202-N are the Rayleigh fading adders 102-0 to 102-N and the attenuator 103- of FIG.
This is a combination of variations due to 0 to 103-N.

The MLSE starts with the complex gain adder 202.
Estimate −0 to 202−N by using a unique word inserted in the data. Complex gain adder 202-
Since the line model can be reproduced by knowing 0 to 202-N, the estimated complex gain adder 202-0 is set with the past transmission data 200 accumulated by the delay units 201-0 to 201- (N-1) as a state. A replica is generated using the filter of FIG. 14 in which ˜202-N is set, and the transmission sequence is estimated by Viterbi decoding.

However, since there are cases where MLSE can reduce the error rate to some extent, MLS
An error correction code is used in combination with E. The convolutional encoder 2 generates a plurality of bits each time one bit of the transmission data 1 enters, together with the state of the past several bits. For example, if the coding rate is 1/2, 2 bits are generated for every 1 bit of the transmission data 1. FIG. 15 shows this state. The transmission data 300 is delayed by the delay units 301-0 to 301- (M-1), the complex gain is added by the complex gain adders 302-0 to 302-M, and the exclusive OR circuit 303 performs the exclusive OR. Is taken as the transmission signal 304. Delay device 301-0 to 301
The past transmission data 300 is accumulated by-(M-1), and this is the state when decoding by Viterbi decoding. In the case of the convolutional encoder, the encoder is invariant, and since only bit operations are performed, the complex gain adder 302-0
.About.302-M actually takes only one of the values 0, 1, j and 1 + j. In this case, since the configuration of the encoder in FIG. 15 is known in advance, the Viterbi decoder 7 on the receiving side can decode it by Viterbi decoding.

As described above, in the conventional data transmission apparatus, the distortion of multipath fading is compensated by the equalizer such as MLSE, and the error that cannot be completely compensated is corrected by the error correction code such as convolution and Viterbi decoding. It realizes high quality data transmission.

[0013]

However, in the above-mentioned conventional data transmission apparatus, since the distortion compensation of the line by the equalizer and the error correction by the Viterbi decoder are performed independently, the constraint condition in each series is Since the path becomes independent and the path that cannot be obtained depending on the state of the line among the paths for Viterbi decoding is included in the candidates, the effect of improving the error rate becomes poor.

The present invention has been made in view of the above situation, and simultaneously performs equalization for removing line distortion due to multipath fading and error correction for reducing an error rate to improve reception quality. It is an object of the present invention to provide a receiving device and a transmitting device capable of improving the number of tracebacks and reducing the amount of memory by performing two steps of equalization and error correction in one operation.

[0015]

In order to solve the above problems, the present invention assumes a virtual encoder in which a line model and a convolutional encoder are fused, and performs Viterbi decoding using the virtual encoder. Then, the equalization by MLSE and the Viterbi decoding for the convolutional code are simultaneously performed, thereby improving the error rate characteristic.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention is
It is equipped with a receiving system that simultaneously performs equalization that compensates for distortion due to multipath fading and error correction that decodes error-correction coded data, and can improve error rate characteristics. And has the effect of reducing the amount of memory.

According to a second aspect of the present invention, in the receiving apparatus according to the first aspect, a demodulator in which an equalizer and an error corrector are combined is provided, and the demodulator compensates for distortion and errors in multipath fading. The correction is performed at the same time and has an effect of improving the reception quality.

According to a third aspect of the present invention, in the receiving device according to the second aspect, the demodulator is a virtual code in which a multipath from the encoder on the transmitting side to the antenna of the receiving system is virtually constructed by a digital filter. Since it is provided with a digitizer, it has an effect of being able to simultaneously perform distortion compensation and error correction for multipath fading.

According to a fourth aspect of the present invention, in the receiving apparatus according to the third aspect, the demodulator sets a state in which the distortion of the encoder on the transmission side and the distortion of the line are combined in the virtual encoder, and A candidate signal is provided to the virtual encoder, and means for estimating a transmission data sequence from the error signal between the replica output from the virtual encoder and the received signal is provided, and equalization and convolution by MLSE are provided. Viterbi decoding for the code can be performed at the same time, which has the effect of improving the error rate characteristic.

According to a fifth aspect of the present invention, in the receiving apparatus according to the first aspect, a demodulator for simultaneously performing equalization for compensating for distortion due to multipath fading and error correction for decoding error-correction coded data is provided. A plurality of equalizers for equalizing the received data for each transmission sequence, a CRC inspection means for performing CRC inspection on the demodulated data decoded by the equalizer for each transmission sequence, and a demodulation of each equalizer based on the CRC inspection result. A data frame which is determined to be demodulated by the demodulator when the data is erroneous, and a data frame which is determined to have no error is adopted, and only when all the data frames are determined to be erroneous. By adopting the demodulator result,
This has the effect of improving the frame error rate characteristic of the data frame.

The invention according to claim 6 is generated by encoding the transmission data by receiving the modulated data which is interleaved with the depth of the reciprocal of the coding rate while keeping the order in the sequence on the transmitting side. Modulation data corresponding to multiple transmission sequences are simultaneously subjected to equalization to compensate for distortion due to multipath fading and error correction, and have the effect of correctly demodulating interleaved transmission data. is there.

According to a seventh aspect of the present invention, the transmission side receives the modulation data frequency-hopping between a plurality of frequencies and extracts the modulation data from the specific transmission device in synchronization with the frequency hopping operation. Equalization for compensating for distortion due to multipath fading and error correction are performed at the same time, and it has an effect that the error rate characteristic can be improved even during low-speed fading.

According to an eighth aspect of the present invention, the receiving apparatus according to any one of the first to sixth aspects is subjected to interleaving with the depth of the reciprocal of the coding rate while keeping the order in the sequence. This is a transmitting device that transmits transmission data, and has the effect of being able to demodulate interleaved transmission data even in a receiving device that simultaneously performs equalization and error correction.

The invention described in claim 9 is a transmitting device for transmitting the transmission data frequency-hopping between a plurality of frequencies, to the receiving device according to any one of claims 1 to 6, wherein the fading is slow. Also has the effect that a sufficient interleaving effect can be achieved.

According to a tenth aspect of the present invention, the receiving apparatus according to any one of the first to sixth aspects is modulated by adding a CRC check bit to the transmission data and then encoding using an invertible code. This is a transmitting device for transmitting data, and when the unit to which the CRC check bit is added is a data frame, it has an effect of reducing the frame error rate of the data frame.

According to an eleventh aspect of the present invention, there is provided a mobile station which moves within a cell, comprising a receiving system for simultaneously performing equalization for compensating for distortion due to multipath fading and error correction for decoding error correction coded data. Is a base station device that performs data transmission between the base station and the base station device and has an effect of improving the error rate characteristic in the base station.

According to a twelfth aspect of the present invention, there is provided a receiving system for simultaneously performing equalization for compensating for distortion due to multipath fading and error correction for decoding error-correction coded data, and a base installed in the cell. It is a mobile station device that performs data transmission with a station, and has an effect of improving error rate characteristics in the mobile station.

Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings. (Embodiment 1) FIG. 1 shows a schematic configuration of a data transmission apparatus according to Embodiment 1 of the present invention. The data transmission device according to the present embodiment has a transmission data 50 in the transmission system.
0 is encoded by the convolutional encoder 501 and is modulated by the modulator 502.
After being modulated by, the signal is transmitted from the transmitting antenna 503. In addition, a reception signal received by the reception antenna 504 in the reception system is passed through a wave detector to a UDMV (United Decoder wi
th MLSE and Viterbide coder) 505 to simultaneously perform distortion compensation for multipath fading and error correction by Viterbi decoding to obtain demodulated data 506. The UDMV 505 is a demodulator that combines an MLSE and a Viterbi decoder.

FIG. 2 shows the configuration of the functional blocks of the UDMV 505. The virtual convolutional encoder 511 is a digital filter configured to have a state in which the convolutional encoder 501 of the transmission system and line distortion are fused.
Details of the virtual convolutional encoder 511 will be described later. The channel estimation unit 512 estimates the complex gain coefficient that reproduces the propagation path of the transmission wave using the unique word inserted in the received signal, and sets it in the virtual convolutional encoder 511.
The state estimation unit 513 applies the same modulation as that of the transmission system to the candidate signal corresponding to the number of bits of the transmission signal, and inputs the candidate signal to the virtual convolutional encoder 511. On the other hand, the error signal indicating the error between the replica from the virtual convolutional encoder 511 and the actual received signal is fetched from the adder 515, the path leading to the candidate with a small error is selected, and the paths are connected by the selected path. The data string is output as demodulated data.

In FIG. 3, QPSK is used for modulation when the coding rate is 1/2.
The configuration of a virtual convolutional encoder 511 when modulation is used is shown.

Virtual convolutional encoder 511 shown in FIG.
Is (M + N) delay units 401-0 to 401- (M + N).
-1) is connected in series, a number (= N + 1) of complex gain blocks corresponding to the wave number of the line, and a complex exclusive OR circuit 4 provided corresponding to each complex gain block 4
03-0 to 403-N and a complex exclusive OR circuit 403
Complex gain circuits 404-0 to 404-N that multiply the outputs of −0 to 403-N by a gain that compensates for line distortion, and a complex adder 405 that adds the outputs of the complex gain circuits 404-0 to 404-N. It consists of and.

Each complex gain block has a number of complex gain adders (402-0-0 to 402-0-M) and (402-1) corresponding to the constraint length of the convolutional encoder 501.
-0 to 402-1-M), ... (402-N-0 to 402)
-NM).

The complex gain adders 402-0-0 to 402-0-M forming the uppermost complex gain block are
Data 400 to be input to the first delay device 401-0 in the delay device array and delay devices 401-0 to 401- (M-1)
Delay data are input in parallel according to the order. These complex gain adders 402-0-0 to 402-0-M
The complex exclusive OR circuit of the outputs of the
Calculate with 3-0.

That is, the delay units 401-0 to 401- (M-1) in the virtual convolutional encoder 511, the complex gain adders 402-0-0 to 402-0-M, and the complex exclusive OR circuit 403. -0 has the same filter structure as the convolutional encoder shown in FIG. Since the convolutional encoder 501 of the transmission system has a fixed constraint length and complex gain and is known in advance, the number of delays per complex gain block and the complex gain adders 402-0-0 to 402
Each complex gain (c) of −0−M can be determined.

In the virtual convolutional encoder 511, the delay data group input to each complex gain block is shifted by one delay in block units from the uppermost block to the lowermost block. Delay device 401-0 to 401
By considering each delay due to −N as a delay of each propagation path corresponding to (N + 1) wave numbers, the delay units 401-0 to 401-0
401-N, complex gain adders 404-0 to 404-
The N and complex adder 405 has the same filter structure as the digital filter for compensating for the line distortion shown in FIG. In the UDMV 505, the channel estimation unit 512 estimates the filter coefficient for compensating the distortion according to the current state of each propagation path based on the unique word, and the complex gain adders 404-0 to 404- of the virtual convolutional encoder 511.
Determine the complex gain (p) of N.

The operation of the data transmission device configured as described above will be described. First, in the transmission system, the transmission data 5
00 is subjected to error correction coding by the convolutional coder 501, whereby a series of several bits is generated from the convolutional coder 501 every time 1 bit of the transmission data 500 enters. This sequence is modulated by the modulator 502 and the transmission antenna 5
Send from 03. In the reception system, the reception antenna 504 receives this signal with line distortion added. This received signal is demodulated by UDMV505 and demodulated data 5
06 is obtained.

The operation of the UDMV 505 will now be described. The UDMV 505 is a convolutional encoder 50 on the transmission side.
By having a state in which 1 and line distortion are fused, MLSE
And the error correction by Viterbi decoding are performed at the same time.

In the UDMV 505, the candidate signal provided from the state estimation unit 513 is input as the transmission data 400 to the delay unit 401-0 in the first stage of the delay line via the modulator 514, and the delay units 401-0 to 401- are input. It is sequentially delayed by (M + N-1). On the other hand, first, the complex gain adder 402
After being multiplied by the complex gain (c) in −0-0 to 402-NM, the complex exclusive OR circuits 403-1 to 403-
At N, the exclusive OR of the real part and the imaginary part is calculated. The complex gain adders 402-0-0 to 402-NM correspond to the complex gain adders 302-0 to 302-M in FIG. 15, and take only one of the values 0, 1, (j + 1). . Further, as a correspondence, an arbitrary integer between 0 and N is represented by X, 0 and
If an arbitrary integer between M is Y, 402-XY = 3
02-Y. Complex exclusive OR circuit 403-0-4
03-N is a complex gain adder 402-0-0 to 402
The following calculation is performed on the output of -NM.

403-0: 402-0-0 to 402-0-M complex exclusive-OR 403-1: 402-1-0 to 402-1-M complex exclusive-OR :: 403-N : 402-N-0 to 402-N-M complex exclusive OR circuit The outputs of the complex exclusive OR circuits 403-1 to 403-N are further output to complex gain adders 404-0 to 404-N. It can be multiplied by the gain (p). Complex gain adder 404
-0 to 404-N are the complex gain adders 202 of FIG.
It corresponds to -0 to 202-N and is time-varying.

Complex gain adders 202-0 to 202-N
Are all added by the complex adder 405 to form a reception signal (replica) 406.

According to such an embodiment, the UDMV5
Of the received signal 40 by the virtual convolutional encoder 511 of 05.
6 is uniquely determined by the sequence based on the transmission data 400 held in the delay units 401-0 to 401- (M + N-1), so that if the Viterbi decoding with this sequence as a state is performed, the transmission data 400 The sequence can be estimated. Therefore, equalization and error correction can be performed at the same time. By performing equalization and error correction at the same time, the same effect as a longer constraint length is obtained in the presence of a delayed wave, and the error correction capability is improved compared to performing equalization and error correction independently. . Further, the number of tracebacks and the memory can be reduced as compared with the case where both equalization and error correction are performed.

In the first embodiment, the coding rate is 1/2 and the QPSK modulation is used for modulation. However, in other cases, a virtual encoder can be constructed with the same idea. .

(Second Embodiment) FIG. 4 shows a functional block configuration of a transmission system of a data transmission apparatus according to the present embodiment. The functional block of the receiving system is assumed to be configured by UDMV as in the first embodiment.

The framing section 611 is a section for framing user data. The convolutional encoder 601 performs error correction coding on the frame data to generate a number of transmission sequences corresponding to the coding rate. Interleaver 612 is a part that performs interleaving in which the sequence of the encoded sequences is rearranged and transmitted, and rearrangement is controlled so that each transmission sequence is assigned to a slot. The slotting section 613 slotizes the interleaved transmission sequence and sets pilot (pilot) symbols and transmission power control (tpc) bits. The transmission sequence is inserted into the slot, modulated by the modulator 614, and transmitted from the antenna via the transmission amplifier 615.

FIG. 5 shows the settings of the convolutional encoder 601. The coding rate is 1/2, and the error-correction-coded data becomes two series of transmission series (A) 602 and transmission series (B) 603. Although an example of the coding rate 1/2 is shown, in the case of different coding rates, the number of sequences increases according to the denominator of the coding rate.

The operation of the embodiment configured as described above will be described. The framed transmission data 600 is error-correction-coded by the convolutional encoder 601 and provided to the interleaver 612 as two sequences of a transmission sequence (A) 602 and a transmission sequence (B) 603.

In the present embodiment, the number of sequences is the coding rate 1 /
Since there are two sequences of A and B corresponding to 2, the coding rate 1 /
Interleaving is performed over the reciprocal of 2, that is, two slots. Moreover, the transmission sequence (A) 602 is assigned to the even slot number which becomes the first slot in one transmission,
The transmission sequence (B) 603 is assigned to the odd slot number which becomes the second slot in one transmission.

Expanding when the coding rate = 1 / N, 1
Each transmission is divided into 1st slot to Nth slot corresponding to N, which is the reciprocal of the coding rate, a plurality of transmission sequences are assigned to different slots, and different slot data is assigned to 1 slot. Try not to be denied.

FIG. 6 shows a specific example of randomization by the interleaver 612. 604 is a signal of slot # 0, 605 is a signal of slot # 1, and 606 is a slot # 2.
, And 607 is the signal of slot # 3. For transmission sequence A 602 and transmission sequence B 603, these different transmission sequences are assigned to different slots in order to obtain the interleaving effect while maintaining the order in the sequence.

FIG. 6 is an example in which the transmission data 600 is a data frame for every 6 bits. When Z is 0 to 5,
The first to sixth bits are represented as S (0, Z), and the next 6 bits are represented as S (1, Z) .... Further, when an arbitrary integer is X, the transmission sequence A602 generated for S (X, Z) is A (X, Z), and the transmission sequence B603 generated for S (X, Z) is B. Represented as (X, Z). A (0, Z) is in slot # 0 (604), and A (1,
Z) is in slot # 2 (606), B (0, Z) is in slot # 1 (605), and B (1, Z) is in slot # 3 (607).
, And so on. The slots are temporally separated so that the fading correlation is small.

On the other hand, in the receiving system, slot # 0 (604)
And slot # 1 (605) is received, S (0, Z)
Of slot # 2 (606) and slot # 3 (6
07) is received, S (1, Z) is estimated, and the same is estimated and demodulated thereafter.

In the present embodiment, the UDMV 505 for performing equalization and error correction at the same time is provided in the receiving system by assuming a virtual encoder in which the convolutional encoder in the transmitting system and the line are fused, and therefore the encoding is simply performed. Interleaving cannot be introduced simply by rearranging the order of the subsequent sequences. Therefore, as described above, the transmission sequence (A) 602 and the transmission sequence (B) 60
On the other hand, in order to obtain the interleaving effect while maintaining the order in the sequence, these different transmission sequences are assigned to different slots.

According to such an embodiment, the UDMV
Interleaving can be introduced even when using
The effect of error correction can be improved.

(Embodiment 3) The present embodiment is an example in which slots randomized by the same interleaving as in Embodiment 2 are frequency hopping between a plurality of frequencies and transmitted.

FIG. 7 shows an example of frequency hopping according to this embodiment. This figure is an example using four frequencies, and is the case where four users are transmitting data. Reference numeral 700 is a signal of frequency f1, 701 is a signal of frequency f2, 702 is a signal of frequency f3, and 703 is a signal of frequency f4. f1, f2, f3 and f4 have different frequencies. Each block represents one slot.

Focusing on a certain user 1, frequency hopping is performed like a shaded portion. This user 1 has f1, f2, f4, f3, f1, f3, f4, f for each slot.
Data transmission is performed using frequencies of 1, f3 and f2.

According to such an embodiment, since fading has a smaller correlation with different frequencies, fading in adjacent slots can be made independent without a long time between slots. . As a result, a sufficient interleaving effect can be obtained even for slow fading.

(Embodiment 4) FIG. 8 shows the configuration of functional blocks of the transmission system of the data transmission apparatus according to the present embodiment, and FIG. 9 shows the configuration of functional blocks of the reception system.

The transmission system of this embodiment has a framing unit 921 for framing transmission data, a CRC check bit adder 922 for adding check bits to frame data, an invertible encoder 923, an interleaver 924, and slotting. Unit 925, modulator 926, transmission amplifier 927,
It is composed of an antenna 928 and the like.

The receiving system of the present embodiment has an antenna 90.
0, detector 901, memory A902, memory B903,
Equalizer A904, Equalizer B905, UDMV906, C
It is composed of an RC inspection device A907, a CRC inspection device B908, a selection determination device 909, a selector 910, and the like. UD
The MV 906 is the UDMV 505 described in the first embodiment.
It is a combination of an equalizer and an error corrector. The selection determiner 909 takes in the inspection results of the CRC inspection device A 907 and the CRC inspection device B 908, and gives an instruction of selection data to the selector 910 based on the table shown in FIG.

The operation of the data transmission apparatus configured as above will be described. In the transmission system, the transmission data 800 is CR
A CRC check bit is added by the C check bit adder 801. This allows the receiving side to check whether the received data has an error. Next, the invertible encoder 802 performs invertible coding to form a transmission sequence (A) 803 and a transmission sequence (B) 804.

The invertible code is a transmission sequence (A).
A code for which the original transmission data 800 can be decoded if either 803 or the transmission sequence (B) 804 is obtained, and error correction can be performed if both the transmission sequence (A) 803 and the transmission sequence (B) 804 are obtained. Is. Since the structure of the invertible encoder 802 is the same as that of the convolutional encoder,
The UDMV 906 of the receiving system may have the same configuration as in the first embodiment.

The inversion-encoded transmission sequence (A) 803 and transmission sequence (B) 804 are subjected to the same interleaving as in the second embodiment, and the slotting section 9 is used.
Slot at 25.

FIG. 11 shows a concrete example of interleaved slots. In the transmission of the transmission data S (0, n), the data of the transmission sequence A is inserted into the signal 805 of the slot # 0 which is the first slot, and the transmission sequence B is added to the signal 806 of the slot # 1 which is the second slot. Data is inserted. In the transmission of the transmission data S (1, n), the data of the transmission sequence A is inserted into the signal 807 of the slot # 2 which is the first slot, and the slot # 3 which is the second slot.
The data of the transmission sequence B is inserted into the signal 808 of.

In the receiving system, the signal received by the receiving antenna 900 is first detected by the detector 901, and the even slots are stored in the memory A902 and the odd slots are stored in the memory B903. The equalizer A904 equalizes the signal of the memory A902, and the CRC checker A907 checks the result for whether there is an error. The equalizer B905 equalizes the signal of the memory B903, and the CRC checker B908 checks the result of the equalization. Further, the UDMV 906 demodulates using both the signal of the memory A 902 and the signal of the memory B 903.

The selection determiner 909 uses the selection logic table shown in FIG. 10 to determine the result of the CRC checker A907 and the C
From the result of the RC checker B908, the selector 901 selects the output most appropriate for the output of the equalizer A904, the output of the equalizer B905, and the output of the UDMV906, and the received data 911 is selected.

For example, when the signal quality of the memory A902 is extremely good and the signal quality of the memory B903 is extremely poor, the result of the CRC checker A907 is OK,
The result of the CRC checker B908 is NG. Memory B9
If the 03 signal quality is extremely poor, UDMV90
An error may remain in the output of 6 due to the influence of the memory B903. Therefore, in such a case, the equalizer A90
The output of Equalizer A904 is selected because the output of 4 is the most suitable.

When both the result of the CRC checker A 907 and the result of the CRC checker B 908 are NG, it is expected that the quality of the UDMV 906 will be the best due to error correction. In such a case, the output of the UDMV 906 is selected. To do.

If both the result of the CRC checker A907 and the result of the CRC checker B908 are OK, the equalizer A9
Since the quality of both the output of 04 and the output of the equalizer B 905 is good, the output of one of the equalizers A and B is selected by arbitrary setting.

According to such an embodiment, even if the signal quality of one transmission sequence is extremely poor, the demodulated data expected to have the best quality without being dragged by the poor quality signal can be obtained. If the unit that can be acquired and the CRC check bit is added is a data frame, it is possible to particularly reduce the frame error rate of the data frame.

The data transmission device of each of the above embodiments is applied to a cellular system. A mobile station that freely moves in a cell is equipped with a UDMV compatible with an encoder used in a data transmission device of a base station. In addition, U corresponding to the encoder used in the mobile station data transmission device is used as the base station.
It is equipped with a DMV. By performing the same data transmission between the base station and the mobile station as the transmission system and the reception system of the above-mentioned data transmission device, the transmission quality is improved.

In the above description, the case where the frame data is slotted for data transmission has been described as an example, but the encoding, interleaving, and frequency hopping are not limited to such a format.

[0073]

As described in detail above, according to the present invention, an equalizer for removing line distortion due to multipath fading and an error correction for reducing an error rate can be performed at the same time. An advantageous effect that the quality can be improved can be obtained. Also, since the two steps of equalization and error correction can be performed once, the advantageous effect that the number of tracebacks and the memory amount can be reduced can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a data transmission device according to a first embodiment of the present invention.

FIG. 2 is a functional block diagram of UDMV in the receiving system according to the first embodiment.

FIG. 3 is a functional block diagram of a virtual convolutional decoder provided in UDMV.

FIG. 4 is a functional block diagram of a transmission system of the data transmission device according to the second embodiment of the present invention.

FIG. 5 is an input / output diagram of a convolutional encoder in the transmission system according to the second embodiment.

FIG. 6 is a diagram showing slots with interleaving according to the second embodiment.

FIG. 7 is a diagram showing frequency hopping in the data transmission device according to the third embodiment of the present invention.

FIG. 8 is a functional block diagram of a transmission system of a data transmission device according to a fourth embodiment of the present invention.

FIG. 9 is a functional block diagram of a reception system of the data transmission device according to the fourth embodiment of the present invention.

FIG. 10 is a table configuration diagram of a selection logic in the receiving system according to the fourth embodiment.

FIG. 11 is a diagram showing interleaved slots according to the fourth embodiment.

FIG. 12 is a schematic diagram of a conventional data transmission device.

FIG. 13 is a diagram showing a line model.

FIG. 14 is a filter configuration diagram in which the line model is rewritten in a form close to a digital filter.

FIG. 15 is a block diagram of an encoder

[Explanation of symbols]

401-0 to 401- (M + N-1) delay device 402-0-0 to 402-NM Complex gain adder 403-0 to 403-N complex exclusive OR circuit 404-0 to 404-N complex gain adder 405 complex adder 501, 601 Convolutional encoder 502 modulator 503 transmission antenna 504 reception antenna 505 UDMV 602, 803 Transmission sequence A 603, 804 Transmission sequence B 801 CRC check bit adder 802 Invertible encoder 901 detector 902 memory A 903 memory B 904 Equalizer A 905 Equalizer B 907 CRC checker A 908 CRC checker B 909 Selection determiner 910 Selector

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Osamu Kato             3-1, Tsunashima-Higashi 4-chome, Kohoku-ku, Yokohama-shi, Kanagawa             No. Panasonic Mobile Communicator             Within Chonz Co., Ltd. F-term (reference) 5K014 AA01 BA06 BA10 FA11                 5K022 EE02 EE04 EE35                 5K046 AA05 EE06 EE16 EE37 EE56                       EF15

Claims (12)

[Claims] 1. A receiving apparatus comprising a receiving system for simultaneously performing equalization for compensating for distortion due to multipath fading and error correction for decoding error correction coded data. 2. The receiving system comprises a demodulator in which an equalizer and an error corrector are integrated, and the demodulator simultaneously performs distortion compensation and error correction for multipath fading. 1. The receiving device according to 1. 3. The reception device according to claim 2, wherein the demodulator includes a virtual encoder in which a multipath from the encoder on the transmission side to the antenna of the reception system is virtually constructed by a digital filter. apparatus. 4. The demodulator comprises means for setting, in the virtual encoder, a state in which distortions of the encoder on the transmission side and the line distortion are fused.
4. The receiving apparatus according to claim 3, further comprising means for estimating a transmission data sequence from an error signal between a replica output from the virtual encoder and a received signal while giving a candidate signal to the virtual encoder. 5. A demodulator for simultaneously performing equalization for compensating for distortion due to multipath fading and error correction for decoding error correction coded data, and a plurality of equalizers for equalizing received data for each transmission sequence. CRC check means for CRC checking the demodulated data decoded by the equalizer for each transmission sequence, and selects the demodulated data of the demodulator when the demodulated data of each equalizer is error from the CRC check result. The receiving device according to claim 1, further comprising a selecting unit. 6. The transmission side receives the interleaved modulated data with the depth of the reciprocal of the coding rate while maintaining the order in the sequence, and supports a plurality of transmission sequences generated by encoding the transmission data. A receiving apparatus, which simultaneously performs equalization for compensating distortion due to multipath fading and error correction on the modulated data. 7. The distortion data due to multipath fading is applied to the modulation data from the specific transmission device, which is obtained by receiving the modulation data frequency-hopping between a plurality of frequencies on the transmission side and extracting in synchronization with the frequency hopping operation. A receiving device characterized by performing equalization for compensation and error correction at the same time. 8. Transmitting, to the receiving apparatus according to any one of claims 1 to 6, transmission data subjected to interleaving with a depth that is a reciprocal of a coding rate while maintaining the order in the sequence. And a transmitter. 9. A transmission device, which transmits transmission data subjected to frequency hopping between a plurality of frequencies, to the reception device according to any one of claims 1 to 6. 10. The method according to claim 1, further comprising: transmitting modulation data encoded by using an invertible code after adding a CRC check bit to the transmission data. Characteristic transmitter. 11. A data transmission system including a reception system for simultaneously performing equalization for compensating for distortion due to multipath fading and error correction for decoding error-correction coded data, and transmitting data to and from a mobile station moving in a cell. A base station device characterized by performing. 12. A data receiving system is provided which simultaneously performs equalization for compensating for distortion due to multipath fading and error correction for decoding error-correction coded data, and data is exchanged with a base station installed in a cell. A mobile station device characterized by performing transmission.