JPH02202746A - Data transmission device - Google Patents
Data transmission deviceInfo
- Publication number
- JPH02202746A JPH02202746A JP1022867A JP2286789A JPH02202746A JP H02202746 A JPH02202746 A JP H02202746A JP 1022867 A JP1022867 A JP 1022867A JP 2286789 A JP2286789 A JP 2286789A JP H02202746 A JPH02202746 A JP H02202746A
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- 230000005540 biological transmission Effects 0.000 title claims description 20
- 238000001514 detection method Methods 0.000 claims description 5
- 238000000034 method Methods 0.000 claims description 2
- 230000000694 effects Effects 0.000 description 5
- SYOKIDBDQMKNDQ-XWTIBIIYSA-N vildagliptin Chemical compound C1C(O)(C2)CC(C3)CC1CC32NCC(=O)N1CCC[C@H]1C#N SYOKIDBDQMKNDQ-XWTIBIIYSA-N 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 238000004891 communication Methods 0.000 description 1
- 239000000284 extract Substances 0.000 description 1
- 238000010295 mobile communication Methods 0.000 description 1
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Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は、移動通信、有線通信等に使用するデータ伝送
装置に関する。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a data transmission device used in mobile communications, wired communications, and the like.
従来の技術
第２図は従来のデータ伝送装置の構成を示している。第
２図において、２１はデータインタフェースであり、送
信側の音声コーデック等からデータを受は取り、畳込み
符号化器２２へ渡す。畳込み符号化器２２は受は取った
データに畳込み符号化を施し、Ｇ Ｍ ３ Ｋ （Ｇａ
ｕｓｓｉａｎ −ｆｉｌｔｅｒｅｄ Ｍｉｎｉｍｕｍ
５ｈｉｆｔＫｅ虞ｎｇ）変調器２３へ渡す。ＧＭＳＫ変
調器２３の出力は送信アンテナ２４へ送られ、そこから
放射された電波は受信アンテナ２５で受は取られる。２
６は直交検波器で、受信アンテナ２５から受信した電波
を直交検波し、その同相成分２７と直交成分２８をＤＦ
Ｅ （Ｄｅｃｉｓｉｏｎ Ｆｅｅｄｂａｃｋ Ｅｑｕａ
ｌｉｚｅ） ２９へ出力する。３０は復号器で、ＤＦＥ
２９かも受けた信号を復号し、硬判定ビタビ（Ｖｉｔｅ
ｒｂｉ）復号器３１へ復号データを出力する。ビタビ（
Ｖｉｔｅｒｂｉ）復号（硬判定）された信号はデータイ
ンタフェース３２へ渡され、受信側の音声コーデック等
に渡される。Prior Art FIG. 2 shows the configuration of a conventional data transmission device. In FIG. 2, reference numeral 21 denotes a data interface, which receives and receives data from an audio codec, etc. on the transmitting side, and passes it to a convolutional encoder 22. The convolutional encoder 22 performs convolutional encoding on the received data and generates G M 3 K (Ga
ussian-filtered Minimum
5hiftKe ng) is passed to the modulator 23. The output of the GMSK modulator 23 is sent to a transmitting antenna 24, and the radio waves radiated from there are received by a receiving antenna 25. 2
6 is a quadrature detector which orthogonally detects the radio waves received from the receiving antenna 25 and converts the in-phase component 27 and quadrature component 28 into a DF.
E (Decision Feedback Equa
lize) Output to 29. 30 is a decoder, DFE
29 decodes the received signal and performs hard decision Viterbi (Vite
rbi) Output the decoded data to the decoder 31. Viterbi (
The decoded (hard decision) signal is passed to the data interface 32, and then passed to an audio codec or the like on the receiving side.
次に上記従来例の動作について説明する。第２図におい
て、音声コーデック等のデータは送信側のデータイ／り
７エース２１．を介して、畳込み符号化器２２へ入り、
ビタビ復号が行えるように畳込み符号化を行う。この信
号はシリアルに並べられ、ＧＭＳＫ変調器２３へ送られ
る。ＧＭＳＫ変調器２３では受は取ったデータをＧＭＳ
Ｋ変調し、送信アンテナ２４から放射し、受信側は受信
アンテナ２５でこれを受は取る。直交検波器２６では受
信アンテナ２５で受は取った変調波から、直交検波によ
って検波信号２７．２８を取り出す。ｐ Ｆ Ｅ （Ｄ
ｅｃｉｓｉｏｎ Ｆｅｅｄｂａｃｋ Ｅｑｕａｌｔｚｅ
ｒ） ２９では受は取った検波信号２７．２８を、アイ
バタンか開くように等化し、同相、直交の各々の成分を
交互に出力する。復号器３０ではＤＦＥ２９から受は取
った信号をもとにデータの復号を行う。ここで、復号に
は、前回骨は取った信号と今回受は取った信号とクロッ
クとのＥＸＯＲをとる必要があるため、ＤＦＥの出力は
硬判定値でなければならない。このため、復号器の出力
は硬判定値となり、出力信号は硬判定ビタビ復号器３１
で処理することになる。硬判定ビタビ復号器３１は、受
は増ったデータ系列に対し、硬判定のビタビ復号を行う
もので、畳み込み符号化器２２と対にして用いると誤り
率を改善することができる。データインタフェース３２
では硬判定ピタピ復号器で復号されたデータを受は取り
、受信側の音声コーデック等へ出力する。Next, the operation of the above conventional example will be explained. In FIG. 2, data such as the audio codec is transferred to the transmitter's data input terminal 7ace 21. enters the convolutional encoder 22 via
Convolutional encoding is performed so that Viterbi decoding can be performed. This signal is serially arranged and sent to the GMSK modulator 23. The GMSK modulator 23 converts the received data into GMS
The signal is K-modulated and radiated from the transmitting antenna 24, and is received by the receiving antenna 25 on the receiving side. The orthogonal detector 26 extracts detected signals 27 and 28 from the modulated wave received by the receiving antenna 25 by orthogonal detection. p F E (D
ecision Feedback Equaltze
r) At 29, the receiver equalizes the received detected signals 27 and 28 so as to open the gates, and outputs in-phase and quadrature components alternately. The decoder 30 decodes data based on the signal received from the DFE 29. Here, for decoding, it is necessary to EXOR the signal taken last time, the signal taken this time, and the clock, so the output of the DFE must be a hard decision value. Therefore, the output of the decoder becomes a hard decision value, and the output signal is sent to the hard decision Viterbi decoder 31.
It will be processed with. The hard-decision Viterbi decoder 31 performs hard-decision Viterbi decoding on the increased data sequence, and when used in combination with the convolutional encoder 22, the error rate can be improved. Data interface 32
Then, the data decoded by the hard-decision pita-pi decoder is received and output to an audio codec or the like on the receiving side.
また、ＤＦＥ２９の代わりに検波信号２７．２８を硬判
定し、同相、直交の各々の成分を交互に出力する判定器
を用いた例もあり、やけりビタビ復号の効果により誤り
率を改善することができる。In addition, there is also an example of using a decision device that makes a hard decision on the detected signal 27.28 and outputs in-phase and quadrature components alternately instead of the DFE 29, and the error rate can be improved by the effect of desperate Viterbi decoding. Can be done.
このように、上記従来のデータ伝送装置でも畳込み符号
と硬判定ピタピ復号により誤り率を改善することができ
る。In this way, even in the conventional data transmission apparatus described above, the error rate can be improved by using convolutional codes and hard-decision pita-pi decoding.
発明が解決しようとする課題
しかしながら、上記従来のデータ伝送装置では復号デー
タを得るためには時間差のある同相成分信号と直交成分
信号が必要であり、そこから得られたデータはＯか１と
なるため尤度が決まらず、ビタビ復号には硬判定しか用
いることができない。Problems to be Solved by the Invention However, in the conventional data transmission device described above, in order to obtain decoded data, an in-phase component signal and a quadrature component signal with a time difference are required, and the data obtained therefrom is either O or 1. Therefore, the likelihood cannot be determined, and only hard decisions can be used for Viterbi decoding.
このため大きな誤り率改善が困難という問題があった。For this reason, there was a problem in that it was difficult to significantly improve the error rate.
本発明はこのような従来の問題を解決するものであり、
軟判定のビタビ復号を用いて誤り率の改善を更に大きく
することができる優れたデータ伝送装置を提供すること
を目的とするものである。The present invention solves these conventional problems,
It is an object of the present invention to provide an excellent data transmission device that can further improve the error rate using soft-decision Viterbi decoding.
課題を解決するための手段
本発明は上記目的を達成するために送信側の畳込み符号
化器とＧＭＳＫ変調器の間に差動符号化器を設け、更に
受信側にビット係数発生器を設け、軟判定ビタビ復号器
が使用できるようにし、誤り率の改善を更に大きくする
ようにしたものである。Means for Solving the Problems In order to achieve the above object, the present invention provides a differential encoder between a convolutional encoder and a GMSK modulator on the transmitting side, and further provides a bit coefficient generator on the receiving side. , a soft-decision Viterbi decoder can be used to further improve the error rate.
作用
本発明は上記のような構成により次のような作用を有す
る。すなわち、差動符号化器によって送信データを差動
符号化することにより、受信部に復号器が不用となり、
代りにＤ Ｆ Ｅ （ＤｅｃｉｓｉｏｎＦｅｅｄｂａｃ
ｋ Ｅｑｕａｌｉｚｅｒ）の出力にビット係数発生器よ
り規則的に発生する１又は−１を乗することにより復号
データが得られるため、復号データは軟判定値を得るこ
とができ、軟判定ビタビ復号器を使用することができる
ために、誤り率の改善を硬判定に比べて更に大きくする
ことができる。Effects The present invention has the following effects due to the above structure. In other words, by differentially encoding the transmission data using a differential encoder, a decoder is not required in the receiving section.
Instead D F E (DecisionFeedback
Since decoded data can be obtained by multiplying the output of the bit coefficient generator by 1 or -1, which is generated regularly from the bit coefficient generator, the decoded data can obtain a soft decision value, and the soft decision Viterbi decoder The improvement in error rate can be even greater compared to hard decisions.
実施例
第１図は本発明の一実施例の構成を示すものである。第
１図において１はデータインタフェースで、送信側の音
声コーデック等からのデータを受け、畳込み符号器２へ
送る。畳込み符号化器２は受は取ったデータに畳込み符
号化を施す。３は差動符号化器で、畳込み符号化された
データを差動符号化する。４はＧ Ｍ ＳＫ （Ｇａｕ
ｓｓｉａｎ −ｆｉｌｔｅｒｅｄＭｉｎｉｍｕｍ ５ｈ
ｉｆｔ Ｋｅｙｉｎｇ）変調器で、ココで変調された信
号は電波となって送信アンテナ５がら放射される。６は
受信アンテナ、７は直交検波器で、検波信号として同相
成分８と直交成分９を出力する。Embodiment FIG. 1 shows the configuration of an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a data interface which receives data from an audio codec or the like on the transmitting side and sends it to a convolutional encoder 2. The convolutional encoder 2 performs convolutional encoding on the received data. 3 is a differential encoder which differentially encodes the convolutionally encoded data. 4 is GM SK (Gau
ssian-filteredMinimum 5h
The signal modulated here by the ift Keying) modulator becomes a radio wave and is radiated from the transmitting antenna 5. 6 is a receiving antenna, and 7 is a quadrature detector, which outputs an in-phase component 8 and a quadrature component 9 as detected signals.
１０はＩ） ｆ？ Ｅ （Ｄｅｃｉｓｉｏｎ Ｆｅｅｄ
ｂａｃｋ Ｅｑｕａｌｉｚｅｒ）で、検波信号から軟判
定値１１を出力する。１７はビットクロック再生器で受
信信号からクロックを再生し、ビット係数発生器１２へ
出力する。１２はビット係数発生器でビットクロック再
生器１７からの情報をもとにビット係数（＋１ｏｒ−１
）１３を出力する。ビット係数１３と軟判定値１１を掛
は合わせることによりパ゛
軟判定復号データ１４が得られ、これ→軟判定ビタビ（
Ｖｉｔｅｒｂｉ ）復号器１５へ入り、その出力はデー
タインタフェース１６を介して受信側の音声コーデック
等へ送られる。10 is I) f? E (Decision Feed
back Equalizer) outputs a soft decision value 11 from the detected signal. A bit clock regenerator 17 regenerates a clock from the received signal and outputs it to the bit coefficient generator 12. 12 is a bit coefficient generator which generates bit coefficients (+1 or -1) based on information from the bit clock regenerator 17.
)13 is output. By multiplying and combining the bit coefficient 13 and the soft decision value 11, the soft decision decoded data 14 is obtained, and this → soft decision Viterbi (
(Viterbi) decoder 15, the output of which is sent to an audio codec or the like on the receiving side via a data interface 16.
次に上記実施例の動作について説明する。上記実施例に
おいて、音声コーデック等のデータはデータインタフェ
ース１を介して畳込み符号化器２へ入り、ビタビ復号が
行えるように畳込み符号化を行う。この信号はシリアル
に並べられ、差動符号化器３へ入り、次式により差動符
号化される。Next, the operation of the above embodiment will be explained. In the above embodiment, data such as an audio codec enters the convolutional encoder 2 via the data interface 1 and is convolutionally encoded so as to perform Viterbi decoding. This signal is serially arranged, enters the differential encoder 3, and is differentially encoded using the following equation.
その出力はＧＭＳＫ変調器４でＧＭＳＫ変調を受け、送
信アンテナ５から放射され、受信側のアンテナ６でこれ
を受は取る。この信号は直交検波器７で直交検波され、
検波信号（同相成分８、直交成分９）を得る。ｐ Ｆ
Ｅ （Ｄｅｃｉｓｉｏｎ Ｆｅｅｄｂａｃｋ Ｅｑｕａ
ｌｉｚｅｒ） １０は受は取った検波信号８，９を、ア
イバタンか開くように等化し、同相、直交の各成分を交
互に出力する。これが軟判定値１１である。一方差動符
号化器３を挿入することにより、ＧＭＳＫ（ＭＳＫも可
）の復号は、この軟判定値１１の符号を規則的に変化さ
せることによって得ることができる。すなわちビット係
数発生器１２において、０番目のビットを１とし、ｉ番
目のビット係数１３をＢとすると、
が出力され、これを軟判定値１１に乗することにより軟
判定復号データ１４が得られる。このため、得られた軟
判定復号データ１４の振幅の絶対値は軟判定値１１のそ
れと同じであり、そのまま軟判定するこことが可能であ
る。このため軟判定ビタビ復号器１５が使用可能となる
。軟判定ビタビ復号器１５は受は取った軟判定復号デー
タ１４をもとに軟判定ビタビ復号を行い、その結果をデ
ータインタフェース１６を介して音声コーデック等へ出
力する。The output is subjected to GMSK modulation by a GMSK modulator 4, radiated from a transmitting antenna 5, and received by an antenna 6 on the receiving side. This signal is orthogonally detected by a quadrature detector 7,
A detected signal (in-phase component 8, quadrature component 9) is obtained. pF
E (Decision Feedback Equa
(lizer) 10 equalizes the detected signals 8 and 9 received by the receiver so as to open a door, and outputs in-phase and quadrature components alternately. This is the soft decision value 11. On the other hand, by inserting the differential encoder 3, GMSK (MSK is also possible) decoding can be obtained by regularly changing the sign of this soft decision value 11. That is, in the bit coefficient generator 12, when the 0th bit is set to 1 and the i-th bit coefficient 13 is set to B, the following is output, and by multiplying this by the soft decision value 11, the soft decision decoded data 14 is obtained. . Therefore, the absolute value of the amplitude of the obtained soft decision decoded data 14 is the same as that of the soft decision value 11, and it is possible to perform a soft decision as is. Therefore, the soft-decision Viterbi decoder 15 can be used. The soft-decision Viterbi decoder 15 performs soft-decision Viterbi decoding on the received soft-decision decoded data 14, and outputs the result to an audio codec or the like via a data interface 16.
このように、上記実施例によれば、軟判定値１１にピッ
ト係数１３を乗じて符号を規則的に変化させるだけで済
むため、軟判定値１１の尤度は保持され軟判定のビタビ
復号を行うことができ、硬判定のビタビ復号に比べ誤り
率の改善度をかなり上げることができるという利点を有
する。In this way, according to the above embodiment, it is sufficient to multiply the soft decision value 11 by the pit coefficient 13 and change the sign regularly, so the likelihood of the soft decision value 11 is maintained and soft decision Viterbi decoding is performed. This method has the advantage of significantly improving the error rate compared to hard-decision Viterbi decoding.
なお、上記実施例ではＧＭＳＫ変調を行っているが、Ｍ
３ Ｋ （Ｍｉｎｉｍｕｍ ｐｈａｓｅ ５ｈｉｆｔ
Ｋｅｙｉ９ｇ） テも同様の効果がある。また、受信
側のＤＦＥの代わりに検波信号の同相、直交の各成分を
交互に出力するだけの軟判定器を用いても、硬判定に比
べて誤り率の改善度をかなり上げることができるという
効果がある。In addition, although GMSK modulation is performed in the above embodiment, M
3K (Minimum phase 5hift
Keyi9g) Te has a similar effect. Furthermore, even if a soft decision device that only outputs the in-phase and quadrature components of the detected signal alternately is used in place of the DFE on the receiving side, it is possible to significantly improve the error rate compared to hard decision. effective.
発明の効果
本発明は上記実施例より明らかなように、ＧＭＳＫ（又
はＭＳＫ）変調の前に差動符号化を施すと復号データと
して軟判定値をもっことができることを利用し、軟判定
とタビ復号な行うことにより従来の硬判定ビタビ復号よ
り誤り率の改善度を上げることができるという利点を有
する。Effects of the Invention As is clear from the above embodiments, the present invention takes advantage of the fact that if differential coding is applied before GMSK (or MSK) modulation, more soft decision values can be obtained as decoded data, and soft decision and tabular values can be obtained. By performing decoding, it has the advantage that the error rate can be improved more than conventional hard-decision Viterbi decoding.
第１図は本発明の一実施例におけるデータ伝送装置の概
略ブロック図、第２図は従来のデータ伝送装置の概略ブ
ロック図である。
１・・・データインタフェース（送信側）、２・・・畳
込み符号化器、３・・・差動符号化器、４・・−ＧＭＳ
Ｋ変調器、５・・・送信アンテナ、６・・・受信アン
テナ、７・・・直交検波器、８・・・検波信号（同相成
分）、９・・・検波信号（直交成分）、１０− Ｄ Ｆ
Ｅ （ＤｅｃｉｓｉｏｎＦｅｅｄｂａｃｋ Ｅｑｕａ
ｌｉｚｅｒ） 、１１− 軟判定値、１２・・・ビット
係数発生器、１３・・・ビット係数、１４・・・軟判定
復号データ、１５・・・軟判定ビタビ（Ｖｉｔｅｒｂｉ
）復号器、１６・・・データインタフェース（受信側）
、１７・・・ビットクロック再生器。FIG. 1 is a schematic block diagram of a data transmission device according to an embodiment of the present invention, and FIG. 2 is a schematic block diagram of a conventional data transmission device. 1...Data interface (transmission side), 2...Convolutional encoder, 3...Differential encoder, 4...-GMS
K modulator, 5... Transmission antenna, 6... Receiving antenna, 7... Quadrature detector, 8... Detection signal (in-phase component), 9... Detection signal (quadrature component), 10- DF
E (DecisionFeedback Equa
lizer), 11- Soft decision value, 12... Bit coefficient generator, 13... Bit coefficient, 14... Soft decision decoded data, 15... Soft decision Viterbi (Viterbi)
) decoder, 16... data interface (receiving side)
, 17...Bit clock regenerator.
Claims (5)
、前記畳込み符号化された信号を差動符号化する手段と
、前記差動符号化された信号により搬送波を変調する手
段とを備え、受信側に、受信した信号を直交検波し同相
成分および直交成分を出力する手段と、前記直交検波出
力に基づき伝送路を等化するとともに、同相成分および
直交成分を交互に、軟判定値として出力する手段と、受
信信号のビットクロックに同期して符号反転情報を発生
するビット係数発生器と、前記軟判定値と前記ビット係
数との積をビタビ復号するための軟判定ビタビ復号器と
、を備えたデータ伝送装置。(1) On the transmitting side, a means for convolutionally encoding transmission data, a means for differentially encoding the convolutionally encoded signal, and a means for modulating a carrier wave with the differentially encoded signal. on the receiving side, a means for orthogonally detecting the received signal and outputting an in-phase component and a quadrature component, and a means for equalizing the transmission path based on the output of the quadrature detection, and a soft-decision method for alternately detecting the in-phase component and the quadrature component. a bit coefficient generator that generates sign-inverted information in synchronization with a bit clock of a received signal; and a soft-decision Viterbi decoder for Viterbi-decoding the product of the soft-decision value and the bit coefficient. A data transmission device comprising:
、前記畳込み符号化された信号を差動符号化する手段と
、前記差動符号化された信号により搬送波を変調する手
段とを備えたデータ伝送装置。(2) On the transmitting side, a means for convolutionally encoding transmission data, a means for differentially encoding the convolutionally encoded signal, and a means for modulating a carrier wave with the differentially encoded signal. A data transmission device equipped with
よび直交成分を出力する手段と、前記直交検波出力に基
づき伝送路を等化するとともに、同相成分および直交成
分を交互に、軟判定値として出力する手段と、受信信号
のビットクロックに同期して符号反転情報を発生するビ
ット係数発生器と、前記軟判定値と前記ビット係数との
積をビタビ復号するための軟判定ビタビ復号器とを備え
たデータ伝送装置。(3) On the receiving side, a means for orthogonally detecting the received signal and outputting an in-phase component and a quadrature component, equalizing the transmission path based on the output of the quadrature detection, and alternately outputting the in-phase component and the quadrature component by making a soft decision. a bit coefficient generator that generates sign-inverted information in synchronization with a bit clock of a received signal; and a soft-decision Viterbi decoder for Viterbi-decoding the product of the soft-decision value and the bit coefficient. A data transmission device equipped with.
とを特徴とする請求項（１）または（２）記載のデータ
伝送装置。(4) The data transmission device according to claim 1 or 2, further comprising a GMSK modulator as the modulating means.
を特徴とする請求項（１）または（２）記載のデータ伝
送装置。(5) The data transmission device according to claim 1 or 2, further comprising an MSK modulator as the modulating means.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1022867A JPH07114417B2 (en) | 1989-02-01 | 1989-02-01 | Data transmission equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1022867A JPH07114417B2 (en) | 1989-02-01 | 1989-02-01 | Data transmission equipment |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02202746A true JPH02202746A (en) | 1990-08-10 |
| JPH07114417B2 JPH07114417B2 (en) | 1995-12-06 |
Family
ID=12094652
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1022867A Expired - Fee Related JPH07114417B2 (en) | 1989-02-01 | 1989-02-01 | Data transmission equipment |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07114417B2 (en) |
-
1989
- 1989-02-01 JP JP1022867A patent/JPH07114417B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH07114417B2 (en) | 1995-12-06 |
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