JPH0128551B2 - - Google Patents
Info
- Publication number
- JPH0128551B2 JPH0128551B2 JP55071751A JP7175180A JPH0128551B2 JP H0128551 B2 JPH0128551 B2 JP H0128551B2 JP 55071751 A JP55071751 A JP 55071751A JP 7175180 A JP7175180 A JP 7175180A JP H0128551 B2 JPH0128551 B2 JP H0128551B2
- Authority
- JP
- Japan
- Prior art keywords
- correlation
- output
- transmission
- oscillator
- signal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 230000005540 biological transmission Effects 0.000 claims description 38
- 230000002596 correlated effect Effects 0.000 claims description 11
- 230000001360 synchronised effect Effects 0.000 claims description 7
- 238000010586 diagram Methods 0.000 description 14
- 238000000034 method Methods 0.000 description 7
- 238000001228 spectrum Methods 0.000 description 5
- 238000011084 recovery Methods 0.000 description 3
- 230000008901 benefit Effects 0.000 description 2
- 238000004891 communication Methods 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000013307 optical fiber Substances 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000011069 regeneration method Methods 0.000 description 1
- 230000011664 signaling Effects 0.000 description 1
- 238000000411 transmission spectrum Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/38—Synchronous or start-stop systems, e.g. for Baudot code
- H04L25/40—Transmitting circuits; Receiving circuits
- H04L25/49—Transmitting circuits; Receiving circuits using code conversion at the transmitter; using predistortion; using insertion of idle bits for obtaining a desired frequency spectrum; using three or more amplitude levels ; Baseband coding techniques specific to data transmission systems
- H04L25/497—Transmitting circuits; Receiving circuits using code conversion at the transmitter; using predistortion; using insertion of idle bits for obtaining a desired frequency spectrum; using three or more amplitude levels ; Baseband coding techniques specific to data transmission systems by correlative coding, e.g. partial response coding or echo modulation coding transmitters and receivers for partial response systems
Landscapes
- Physics & Mathematics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
- Dc Digital Transmission (AREA)
Description
【発明の詳細な説明】
この発明は無線デイジタル伝送に於ける相関符
号伝送（パーシヤル・レスポンス）用受信器の構
成に関る。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the configuration of a receiver for correlated code transmission (partial response) in wireless digital transmission.
マイクロ波帯域のデイジタル無線通信は電話回
線のデイジタル化にともない、急速に発展してい
る。光フアイバー伝送も実用期に入り、準ミリ波
以上の周波数帯域開拓と共に実用的価値の高い現
用の周波数帯の周波数有効利用の考えが高まつて
いる。これに伴い、直線伝送で古くから利用され
ていた相関符号伝送方式（パーシヤル・レスポン
ス方式）もその送信スペクトラムの狭さに注目さ
れてマイクロ波帯での利用が検討され、一部では
実用化されていることは当業者の周知の事実であ
る。例えば相関符号伝送に付いては1975年９月発
行のIEEEのトランザクシヨンCOM−23巻、No.９
921頁から934頁記載のパーシヤル・レスポンス
シグナリング（Portial・Response Signaling）
またマイクロ波帯の実用化に付いてはIEEEの
1977年６月に開催されたインターナシヨナルコン
フアレンスオンコミニケイシヨンズ
（International Conference Communications）
のコンフアレンズ・レコードに記載の“モジユレ
ーシヨンコンシデレイシヨンズフオザDRS−８
91Mb／Ｓデジタル“ラジオ”（modulation
Consideration for the DRS−８ 91Mb／Ｓ
Digital Radio）に各々述べられている。 Digital wireless communication in the microwave band is rapidly developing with the digitization of telephone lines. Optical fiber transmission has entered the practical stage, and along with the development of frequency bands beyond sub-millimeter waves, the idea of effective use of frequencies in current frequency bands with high practical value is increasing. Along with this, the correlation code transmission method (partial response method), which has been used for a long time in straight line transmission, has attracted attention due to its narrow transmission spectrum, and its use in the microwave band has been considered, and in some cases it has not been put into practical use. It is a well-known fact to those skilled in the art. For example, regarding correlated code transmission, see IEEE Transactions COM-Volume 23, No. 9, published September 1975.
Portial Response Signaling described on pages 921 to 934
Regarding the practical application of microwave bands, the IEEE
International Conference Communications held in June 1977
“Modulation Considerations DRS-8” written in the conference record of
91Mb/S digital “radio” (modulation
Consideration for the DRS-8 91Mb/S
Digital Radio).
相関符号伝送に於いては、符号間に相関を付加
する為、送信するデータのレベル数が元データの
それより増加する。従つて受信器で扱うレベル数
が多くなり、搬送波再生処理、並びに信号識別処
理も大がかりになる。送信側で付加された相関を
受信側でほぐし相関消去を施すことにより受信器
で扱うレベル数は元データのものに戻り少くな
る。しかしこの処理は過去の識別結果を利用する
ため識別誤りの影響が時間的に尾を引いて誤り特
性を劣化させることから伝統的に有線伝送ではあ
まり採用されてこなかつた。 In correlated code transmission, since correlation is added between codes, the number of levels of transmitted data is greater than that of the original data. Therefore, the number of levels handled by the receiver increases, and carrier wave recovery processing and signal identification processing also become extensive. By loosening the correlation added on the transmitting side and canceling the correlation on the receiving side, the number of levels handled by the receiver returns to that of the original data and is reduced. However, since this process uses past identification results, the influence of identification errors lingers over time and degrades error characteristics, so it has traditionally not been widely adopted in wired transmission.
無線伝送に於いては扱うデータが高速であると
言うことも原因して装置の単純さがより第一義的
に考えられることから相関消去を利用した受信器
構成のメリートは大きい。この場合、復調特性の
優れた同期検波を行うとすると搬送波再生技術が
必要となる。 In wireless transmission, the simplicity of the device is more important because the data handled is at high speed, so a receiver configuration using correlation cancellation has great benefits. In this case, carrier wave regeneration technology is required if synchronous detection with excellent demodulation characteristics is to be performed.
本発明の目的は、相関消去を採用することによ
り信号識別、搬送波再生に関る装置が簡単な受信
器を提供することにある。 SUMMARY OF THE INVENTION An object of the present invention is to provide a receiver with simple apparatuses for signal identification and carrier wave recovery by employing correlation cancellation.
この発明によれば送信データで変調された第１
の直交振幅変調波が相関付加波器を通過後、第
２の直交振幅変調波となつて甲なる搬送周波数で
受信されるとみなせる相関符号搬送波伝送方式に
おいて甲なる搬送周波数を再生する発振器と；前
記発振器出力を参照信号とする同期検波器と；第
１の直交振幅変調波に対して信号識別と、前記甲
なる搬送周波数と前記発振器との位相差とを検出
し、信号識別値と位相差を各々出力する第１の直
交振幅変調波用復調器と；前記信号識別値a^o並び
に前記a^oよりｉ番先行した値a^o-iによりN
〓i=1
fi・a^o-i
（Ｎ、ｉは非負整数、fiは係数）なる信号を合成
する相関消去波器と；前記同期検波器出力より
前記相関消去波器出力を減じ、出力を前記復調
器に供給する減算器とを用いて；前記信号識別値
より前記送信データを得、前記位相差に応じて前
記発振器の周波数を変化させ搬送波同期を維持す
る相関符号搬送波伝送受信器が得られる。 According to the invention, the first
an oscillator that reproduces the first carrier frequency in a correlation code carrier transmission system in which the orthogonal amplitude modulated wave passes through the correlation adder and becomes a second orthogonal amplitude modulated wave and is received at the first carrier frequency; a synchronous detector using the oscillator output as a reference signal; detecting a signal identification for the first orthogonal amplitude modulated wave and a phase difference between the first carrier frequency and the oscillator, and detecting the signal identification value and the phase difference; a first orthogonal amplitude modulated wave demodulator that outputs N 〓 i=1 f i・a^ oi by the signal identification value a^ o and the i -th preceding value a^ oi from the above a^ o .
(N, i is a non-negative integer, f i is a coefficient); a subtracter that subtracts the output of the correlation canceler from the output of the synchronous detector and supplies the output to the demodulator; A correlation code carrier wave transmission receiver is obtained which obtains the transmission data from the signal identification value, changes the frequency of the oscillator according to the phase difference, and maintains carrier synchronization.
この発明は開発ずみの従来の受信器の構成要素
を十分に生かして、さらに高密度な相関符号信号
を扱う受信器を構成することができるものであ
る。 The present invention makes it possible to make full use of the components of the conventional receiver that has been developed to construct a receiver that can handle higher-density correlation code signals.
次に本発明に付いて図面を参照して詳細に説明
する。 Next, the present invention will be explained in detail with reference to the drawings.
第１図ａは相関符号伝送の１種で最もよく利用
されているデユオバイナリー（Duobinary）と呼
ばれ送信方式に用いられる送信パルスを示してい
る。同パルスの特長は中央部の２点で１をとる外
は周期Ｔで正確に零を横切つているランダム・パ
ルスakを同パルス波形を用いて周期Ｔで次々に伝
送すると、受信側では周期Ｔでyk＝ak＋ak-1なる
値が観測でき、akに対し相関を付加されたパルス
列ykが伝送されていることになる。第１図の波形
１００は同ｂ，ｃに示した波形１０１，１０２の
和として考えられる。波形１０１，１０２は通常
のナイキスト伝送用の送信パルスで中央の１点で
１をとる外は周期Ｔで全て零を横切つている。 FIG. 1a shows a transmission pulse used in a transmission system called Duobinary, which is one of the most commonly used types of correlation code transmission. The characteristic of this pulse is that it crosses zero exactly at a period T except for taking 1 at two points in the center.If a random pulse a k is transmitted one after another at a period T using the same pulse waveform, on the receiving side, A value of y k =a k +a k-1 can be observed in period T, which means that a pulse train y k to which a correlation is added to a k is being transmitted. Waveform 100 in FIG. 1 can be considered as the sum of waveforms 101 and 102 shown in FIG. 1b and c. Waveforms 101 and 102 are normal transmission pulses for Nyquist transmission, and except for one point at the center, which takes 1, they all cross zero at period T.
第２図は第１図ａ，ｂおよびｃより、波形１０
０を発生する相関付加波器ブロツク１０００の
構成を示すブロツク図である。参照数字１はＴ秒
遅延回路２は加算器、３はπ/Tをカツト・オフと
する理想低域波器ないしはπ/Tを遮断周波数と
するロール・オフ波器である。 Figure 2 shows the waveform 10 from Figure 1 a, b and c.
2 is a block diagram showing the configuration of a correlation adder block 1000 that generates 0. FIG. Reference numeral 1 indicates a T-second delay circuit 2, which is an adder, and 3 indicates an ideal low-frequency wave generator with a cut-off of π/T or a roll-off wave generator with a cut-off frequency of π/T.
第３図は第１図の波形１００と同１０１のスペ
クトラムを比較したものであり第３図４が前者の
それ、５が後者のそれを各々示している。６は
π／Ｔ周波数を示している。 FIG. 3 compares the spectra of waveforms 100 and 101 in FIG. 1, with FIG. 3 showing the spectrum of the former waveform 4 and that of the latter waveform 5. 6 indicates the π/T frequency.
また相関付加波器の構成についても第２図の
ものに限らず、結果的にそれと同一の周波数特
性、すなわち第３図の４の特性を持つた波器で
あればそれと置換えることが可能である。 Furthermore, the configuration of the correlation addition waveform is not limited to that shown in Figure 2, but any waveform that has the same frequency characteristics as that shown in Figure 3, i.e., characteristics 4 in Figure 3, can be replaced. be.
従つて送信用の波はベース・バンド帯、中間
周波数帯、または無線周波数帯のいづれで行つて
も良いことになる。 Therefore, the transmission wave may be transmitted in the base band, intermediate frequency band, or radio frequency band.
この図より明らかな様に相関符号伝送では周期
Ｔでパルスを次々と伝送するにも関らず、そのス
ペクトラムはπ/T以内に帯域制限することが装置
の実現性を含めてそれが許されることが特長であ
る。すなわち通常の波形１０１を用いたナイキス
ト伝送に比較してより狭い帯域で同一のデータを
伝送できる訳である。 As is clear from this figure, even though pulses are transmitted one after another with a period of T in correlated code transmission, it is permissible to limit the spectrum to within π/T, including the feasibility of the device. This is a feature. That is, compared to Nyquist transmission using the normal waveform 101, the same data can be transmitted in a narrower band.
第４図は同一のデータをナイキスト伝送と相関
符号伝送で送信した時の各々の波形をａ，ｂに示
す。ｂはそのスペクトラムが狭くなつた見返りと
して受信レベルが２値から３値へと増加している
ことが分る。すなわち、＋２、０、−２の３値とな
つている。 In FIG. 4, waveforms a and b are shown when the same data is transmitted by Nyquist transmission and correlation code transmission. As for b, it can be seen that as a result of the narrowing of the spectrum, the reception level increases from binary to ternary. That is, it has three values: +2, 0, and -2.
第５図は従来の相関符号伝送に用いられるプ
リ・コーテイング形（Pre−coding）の受信器２
０００の例を示すブロツク図である。一般にＬ値
の入力データに対し、受信器側でモシヨローＬに
より複調できる様にプリ・コーダ７でプリ・コー
デイングした後相関付加波器１０００を通し伝
送し、受信器ではＬ値より多い多値レベル識別器
８とモジユローＬ回路９によつて送信データを再
生するものである。同受信器は帰還路を含まない
構成になつているので、識別誤りが次の識別に波
及する欠点がないが多値レベル識別器が複雑にな
る。 Figure 5 shows a pre-coding type receiver 2 used in conventional correlation code transmission.
FIG. 2 is a block diagram showing an example of 000. In general, L value input data is pre-coded by a pre-coder 7 so that it can be modulated by mosiorro L on the receiver side, and then transmitted through a correlation adder 1000. Transmission data is reproduced by a value level discriminator 8 and a modulus L circuit 9. Since the receiver has a configuration that does not include a feedback path, it does not have the disadvantage that a discrimination error affects the next discrimination, but the multi-level discriminator becomes complicated.
第６図は従来の識別値帰還形受信器２０００′
を示すブロツク図である。 FIG. 6 shows a conventional discrimination value feedback type receiver 2000'
FIG.
この場合、先に示した様なプリ・コーテイング
は行なわず送信データは相関付加波器を通過後
送信される。 In this case, the pre-coating as described above is not performed and the transmission data is transmitted after passing through the correlation adder.
受信器２０００′ではまずＴ時間前の識別値が
遅延回路１５を通して減算器１６へ加えられ、送
信側で付加した相関をほぐし、もとのＬ値のデー
タにもどしＬ値識別器１４で元のデータを識別す
る形になつている。同受信器は識別をＬ値で行え
る点が利点であるが、識別誤りが次の識別に波及
する欠点を持つ。 In the receiver 2000', first, the identification value before T time is applied to the subtracter 16 through the delay circuit 15, and the correlation added on the transmitting side is loosened, and the data is returned to the original L value data. It is designed to identify data. The advantage of this receiver is that it can perform identification using the L value, but it has the disadvantage that an error in identification affects the next identification.
第７図ａ，ｂは相関符号伝送の技術を直交振幅
変調方式へ応用した例を説明するための図であ
る。搬送波伝送ではsinwotとcoswotとに各々独
立なデータを変調して伝送できる。これを位相平
面に表現したのが第７図である。同図ａは４相位
相変調方式と呼ばれており同相成分Ｉと直交成分
Ｑに各々２値の変調を掛けたものである。従つて
４つの信号点７００，７０１，７０２および７０
３は２ビツトの情報に対応している。 FIGS. 7a and 7b are diagrams for explaining an example in which the correlation code transmission technique is applied to the orthogonal amplitude modulation method. In carrier wave transmission, independent data can be modulated and transmitted to sinwot and coswot. FIG. 7 shows this on a phase plane. 4A is called a four-phase phase modulation method, in which the in-phase component I and the quadrature component Q are each subjected to binary modulation. Therefore four signal points 700, 701, 702 and 70
3 corresponds to 2-bit information.
第４図から分る様に第７図ａを相関付加波器
に通すと同ｂの様に９つの信点点７０４〜７１２
までの３×３の９値QAM（振幅位相変調波）に
変化する。これを直交相関符号伝送方式と呼んで
いる。 As can be seen from Fig. 4, when Fig. 7 a is passed through a correlation addition waveform, nine believe points 704 to 712 are obtained as shown in Fig. 7 b.
It changes to 3x3 9-value QAM (amplitude phase modulated wave). This is called an orthogonal correlation code transmission method.
本発明は直交相関符号伝送方式の受信器を先の
識別値帰還形の構成とし、搬送波再生処理に付い
ても同一の識別値を用いて行う受信器を提案する
ものである。 The present invention proposes a receiver using the orthogonal correlation code transmission system having the above-mentioned discrimination value feedback type configuration, and using the same discrimination value for carrier wave recovery processing.
第８図は本発明の一実施例のブロツク図を示す
図である。 FIG. 8 is a diagram showing a block diagram of one embodiment of the present invention.
ブロツク２０は同期検波器で掛算器２１，２
２、π/2移相器２３、低域通過波器２４，２５
から成つていて、入力端子２００へ加わる受信信
号を複素ベース・バンド信号へ変換する。ブロツ
ク３０は複素減算器で減算器３１，３２から成つ
ていて、先行符号からの相関を減ずる役目をはた
す。ブロツク４０は４相位相変調波用信号識別器
で直交同相２つの入力に対し各々その極性を出力
する構成のもの。 Block 20 is a synchronous detector and multipliers 21, 2
2, π/2 phase shifter 23, low pass wave generator 24, 25
converts the received signal applied to input terminal 200 into a complex baseband signal. Block 30 is a complex subtracter, consisting of subtractors 31 and 32, which serves to subtract the correlation from the preceding code. Block 40 is a signal discriminator for four-phase modulated waves, and is configured to output the polarity of each of two orthogonal and in-phase inputs.
ブロツク５０は相関消去波器を示し、Ｔ時間
遅延回路５１，５２、係数fiを掛ける係数掛算器
５３，５４より成る。同複素出力は先の減算器に
加えられる。ブロツク７０は４相位相変調波用搬
送波位相誤差検出器で極性反転回路７２、複素掛
算器７１より成る。複数ベース・バンド入力値を
akその識別値をa^iとするとIn｛ak・a^k *｝を出力し
前記位相誤差θeに対しsinθeを出力する。同出力
は電圧制御発振器６０（VCO＝volfage
Confrolled Oscillator）に加えられθeを零にする
様周波数が変化する。 Block 50 represents a correlation canceller, and is comprised of T time delay circuits 51, 52, and coefficient multipliers 53, 54 for multiplying by the coefficient fi . The complex output is added to the previous subtractor. Block 70 is a carrier wave phase error detector for four-phase phase modulated waves, and is composed of a polarity inversion circuit 72 and a complex multiplier 71. Multiple baseband input values
If the identification value of a k is a^ i , then In {a k ·a^ k * } is output, and sin θ e is output for the phase error θ e . The same output is a voltage controlled oscillator 60 (VCO=volfage
Confrolled Oscillator) and the frequency changes so that θ e becomes zero.
ブロツク４０と７０が第１の直交振幅変調用復
調器を構成していることになる。 Blocks 40 and 70 constitute a first quadrature amplitude modulation demodulator.
以上の様に本発明によれば受信器が３×３の９
値QAM（第２の直交振幅変調波）を受信してい
るにも関らず、その信号識別回路、並びに搬送波
位相誤差検出器は第１の直交振幅変調波である４
相位相変調波用のもので良いことになる。 As described above, according to the present invention, the receiver has 3×3 9
Even though it is receiving the value QAM (second quadrature amplitude modulated wave), its signal identification circuit as well as the carrier phase error detector are receiving the first quadrature amplitude modulated wave.
One for phase-phase modulated waves will suffice.
同様にして４×４の16値QAMに対する第２の
直交振幅変調波は第２図の相関付加波器によれ
ば７×７の49値QAMになり、この様な超多値の
識別回路、位相誤差検出器は非常に複雑になるこ
とが予想される。従つて本発明によればこれらは
16値QAM用のもので良いことになり、その構成
は明らかに簡単なものとなる。 Similarly, the second orthogonal amplitude modulated wave for 4 x 4 16-value QAM becomes 7 x 7 49-value QAM according to the correlation adder shown in Fig. 2, and such a super multi-value identification circuit, It is expected that the phase error detector will be very complex. Therefore, according to the present invention, these
A 16-level QAM one will suffice, and its configuration will be obviously simple.
第１図は相関符号伝送を説明するための波形
図、第２図は相関符号を作る相関付加波器のブ
ロツク図を示す図、第３図は相関符号と無相関符
号のスペクトラムを比較する為の図、第４図は相
関符号と無相関符号の送信波形を各々説明する為
の図、第５図は従来の相関符号伝送用の送受信器
構成を示すブロツク図、第６図は従来の相関符号
伝送用の識別値帰還形の受信器の構成を示すブロ
ツク図、第７図は第１の直交振幅変調波である４
相位相変調波と同波形を相関付加波器（第２
図）を通し、第２の直交振幅変調波に変化される
ことを説明した図。第８図は本発明の実施例のブ
ロツク図を示す図。
図中２０が同期検波器、３０が減算器、５０が
相関消去波器、６０が発振器、４０＋７０が復
調器を各々示す。
Figure 1 is a waveform diagram for explaining correlated code transmission, Figure 2 is a diagram showing a block diagram of a correlation adder that creates a correlated code, and Figure 3 is for comparing the spectra of correlated codes and uncorrelated codes. Figure 4 is a diagram for explaining the transmission waveforms of correlated codes and uncorrelated codes, respectively. Figure 5 is a block diagram showing the configuration of a conventional transmitter/receiver for correlated code transmission. Figure 6 is a diagram for explaining the transmission waveforms of correlated codes and uncorrelated codes. A block diagram showing the configuration of a discrimination value feedback type receiver for code transmission, FIG. 7 shows the first quadrature amplitude modulated wave 4.
The same waveform as the phase modulation wave is applied to the correlation addition waveform (second
FIG. FIG. 8 is a diagram showing a block diagram of an embodiment of the present invention. In the figure, 20 is a synchronous detector, 30 is a subtracter, 50 is a correlation canceller, 60 is an oscillator, and 40+70 is a demodulator.
Claims (1)
波が相関付加波器を通過後、第２の直交振幅変
調波となつて甲なる搬送周波数で受信されるとみ
なせる相関符号搬送波伝送方式において、甲なる
搬送周波数を再生する発振器と、前記発振器出力
を参照信号として受信々号を同期検波する同期検
波器と、第１の直交振幅変調波に対して信号識別
と、前記甲なる搬送周波数と前記発振器との位相
差とを検出し、信号識別値と位相差を各々出力す
る第１の直交振幅変調波用復調器と、前記信号識
別値a^o並びに前記a^oよりｉ番先行した値a^o-iによ
りN 〓i=1 fi・a^o-i（Ｎ、ｉは非負整数、fiは係数）なる
信号を合成する相関消去波器と；前記同期検波
器出力より前記相関消去波器出力を減じ、出力
を前記復調器に供給する減算器とを用いて、前記
信号識別値より前記送信データを得、前記位相差
に応じて前記発振器の周波数を変化させ搬送波同
期を維持することを特徴とする相関符号搬送波伝
送受信器。[Scope of Claims] 1. A correlation that can be regarded as a first orthogonal amplitude modulated wave modulated by transmission data passes through a correlation adder, becomes a second orthogonal amplitude modulated wave, and is received at a higher carrier frequency. In the code carrier wave transmission system, an oscillator for reproducing a first carrier frequency, a synchronous detector for synchronously detecting received signals using the output of the oscillator as a reference signal, signal identification for the first orthogonal amplitude modulated wave, and the a first orthogonal amplitude modulated wave demodulator that detects a phase difference between the carrier frequency and the oscillator and outputs a signal identification value and a phase difference, respectively; and the signal identification value a^ o and the a^ o . a correlation canceller that synthesizes a signal N 〓 i=1 f i・a^ oi (N, i is a non-negative integer, f i is a coefficient) using the i- th preceding value a^ oi; and the output of the synchronous detector. The transmission data is obtained from the signal identification value using a subtracter that subtracts the output of the correlation canceling waveformer from the output signal and supplies the output to the demodulator, and changes the frequency of the oscillator according to the phase difference to generate a carrier wave. A correlated code carrier transmission receiver characterized in that it maintains synchronization.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7175180A JPS56168460A (en) | 1980-05-29 | 1980-05-29 | Correlative code carrier wave transmission receiver |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7175180A JPS56168460A (en) | 1980-05-29 | 1980-05-29 | Correlative code carrier wave transmission receiver |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS56168460A JPS56168460A (en) | 1981-12-24 |
| JPH0128551B2 true JPH0128551B2 (en) | 1989-06-02 |
Family
ID=13469540
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7175180A Granted JPS56168460A (en) | 1980-05-29 | 1980-05-29 | Correlative code carrier wave transmission receiver |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS56168460A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7508882B2 (en) * | 2003-12-04 | 2009-03-24 | Alcatel-Lucent Usa Inc. | Electrical backplane transmission using duobinary signaling |
-
1980
- 1980-05-29 JP JP7175180A patent/JPS56168460A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS56168460A (en) | 1981-12-24 |
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