JPH0479438A - Synchronism acquisition system for spectrum spread communication - Google Patents
Synchronism acquisition system for spectrum spread communicationInfo
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- JPH0479438A JPH0479438A JP2190277A JP19027790A JPH0479438A JP H0479438 A JPH0479438 A JP H0479438A JP 2190277 A JP2190277 A JP 2190277A JP 19027790 A JP19027790 A JP 19027790A JP H0479438 A JPH0479438 A JP H0479438A
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- 238000001228 spectrum Methods 0.000 title claims description 16
- 238000004891 communication Methods 0.000 title claims description 14
- 238000000034 method Methods 0.000 claims description 18
- 230000001360 synchronised effect Effects 0.000 claims description 7
- 238000001514 detection method Methods 0.000 claims description 5
- 230000005540 biological transmission Effects 0.000 abstract description 6
- 238000010586 diagram Methods 0.000 description 8
- 230000007423 decrease Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 1
- 230000014759 maintenance of location Effects 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、スペクトラム拡散通信方式における受信側の
同期捕捉方式に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a synchronization acquisition method on the receiving side in a spread spectrum communication method.
従来、スペクトラム拡散通信では、送信機及び受信機に
おいて、スペクトルの拡散及び逆拡散に使うＰＮ符号を
同期させる方法として、スライデング相関方式がある。Conventionally, in spread spectrum communication, there is a sliding correlation method as a method for synchronizing PN codes used for spreading and despreading of spectrum in a transmitter and a receiver.
（例えば電子情報通信学会スペクトル拡散通信研究会５
Ｓ８８−２１．２５頁参照）
このスライデング相関方式では、受信機のＰＮ符号発生
器を送信機のＰＮ符号発生器と異なるクロック速度で動
作させ、送受信機のＰＮ符号間の相対位置をずらしなが
ら両ＰＮ符号の相互相関値を求め、その値がスレッショ
ルドレベルより大きくなったら同期が完了したものとし
て、受信機のＰＮ符号発生機のクロック速度を送信機の
ものと同じにすることにより、同期捕捉を行なっていた
。(For example, Institute of Electronics, Information and Communication Engineers Spread Spectrum Communication Study Group 5
(See page S88-21.25) In this sliding correlation method, the PN code generator of the receiver is operated at a different clock speed than the PN code generator of the transmitter, and the relative positions between the PN codes of the transmitter and receiver are shifted. The cross-correlation value of the PN code is determined, and when the value becomes larger than the threshold level, synchronization is assumed to be complete. Synchronization acquisition is achieved by making the clock speed of the PN code generator of the receiver the same as that of the transmitter. I was doing it.
上述した従来のスライディング相関方式は、同期捕捉の
判定に相互相関値のスレッショルドレベルを用いている
ので、通信伝路路のノイズ等によって、相互相関値が低
下しピーク値がスレッショルドレベルよりも小さくなる
と、同期捕捉ができなくなるという欠点がある。The conventional sliding correlation method described above uses the threshold level of the cross-correlation value to determine synchronization acquisition, so if the cross-correlation value decreases due to noise in the communication path and the peak value becomes smaller than the threshold level, , the disadvantage is that synchronized acquisition becomes impossible.
本発明の目的は、同期捕捉の判定をスレッショルドレベ
ルを用いずに相互相関値のピークを検出することにより
判定することにより、相互相関関係が低下しても同期捕
捉をできるようにしたスペクトラム拡散通信の同期捕捉
方式を提供することにある。An object of the present invention is to provide spread spectrum communication in which synchronization can be acquired even when the cross-correlation decreases by determining synchronization acquisition by detecting the peak of the cross-correlation value without using a threshold level. The purpose of this invention is to provide a synchronous acquisition method.
本発明のスペクトラム拡散通信の同期捕捉方式の構成は
、符号系列が同じで符号位相が異なる複数の疑似ランダ
ム（以下ＰＮという）符号をクロックに同期して発生ず
るＰＮ符号発生手段と、前記複数のＰＮ符号と受信信号
との相互相関をそれぞれ求める複数の相関手段と、前記
受信信号のクロック速度を送信側のクロックと異ならせ
ることにより、送受信機のＰＮ符号間の相対位置を変化
させる位相可変手段と、前記位相を可変させて相互相関
のピークを検出するピーク検出手段と、このピーク検出
手段が一方の相互相関のピークを検出した時の符号位相
差に等しい送受信機のＰＮ符号の相対位相をずらして他
方の相互相関のピークを検出した時、前記クロック速度
を送信側と一致させるクロック速度制御手段とを含むこ
とを特徴とする。The configuration of the synchronization acquisition method for spread spectrum communication of the present invention includes a PN code generation means for generating a plurality of pseudorandom (hereinafter referred to as PN) codes in synchronization with a clock, and a plurality of a plurality of correlation means for respectively determining cross-correlation between the PN code and the received signal; and a phase variable means for varying the relative position between the PN codes of the transmitter and receiver by making the clock speed of the received signal different from the clock on the transmitting side. and peak detection means for detecting the peak of the cross-correlation by varying the phase, and a relative phase of the PN code of the transmitter/receiver that is equal to the code phase difference when the peak detection means detects the peak of one of the cross-correlation. The present invention is characterized in that it includes clock speed control means for making the clock speed coincide with that on the transmitting side when the other cross-correlation peak is detected.
本発明において、符号位相の異なる複数のＰＮ符号が２
系列または４系列であることができる。In the present invention, a plurality of PN codes with different code phases are
It can be a series or 4 series.
次に、本発明について図面を参照して説明する。 Next, the present invention will be explained with reference to the drawings.
第１図は本発明の一実施例を説明する同期捕捉部のブロ
ック図である。ＰＮ符号発生器１０は同一符号系列で符
号位相が１８０°異なる２組のＰＮ符号を発生し、相関
器８は受信信号と一方のＰＮ符号との相互相関値を出力
し、相関器９は、受信信号と他方のＰＮ符号の相互相関
値を出力し、同期捕捉制御部１２は、それぞれの相互相
関値のピークを検出することにより、クロック発生器１
１のクロック速度を制御し、クロック発生器１１はＰＮ
符号発生用クロックを供給する。FIG. 1 is a block diagram of a synchronization acquisition section illustrating an embodiment of the present invention. The PN code generator 10 generates two sets of PN codes that have the same code sequence but differ in code phase by 180 degrees, the correlator 8 outputs the cross-correlation value between the received signal and one PN code, and the correlator 9 The synchronization acquisition control unit 12 outputs the cross-correlation values of the received signal and the other PN code, and detects the peaks of the respective cross-correlation values.
1, and the clock generator 11 controls the clock speed of PN
Supply clock for code generation.
スペクトラム拡散通信においては、第２図に示すように
、送信機１において、送信データは変調器３によってス
ペクトル拡散された後伝送路７へ送出される。一方、受
信機２では、伝送路から入力される受信信号を復調器４
により、逆拡散して受信データの復調を行なう。この受
信側において、正しく復調されるためには、送信側のＰ
Ｎ符号と受信側のＰＮ符号の位相とを同期させる必要が
ある。In spread spectrum communication, as shown in FIG. 2, in a transmitter 1, transmission data is spread spectrum by a modulator 3 and then sent to a transmission path 7. On the other hand, in the receiver 2, the received signal input from the transmission path is sent to the demodulator 4.
The received data is demodulated by despreading. On the receiving side, in order to demodulate correctly, the transmitting side's P
It is necessary to synchronize the phase of the N code and the PN code on the receiving side.
第３図は送・受信ＰＮ符号の相対位相に対して、相関器
８の出力Ａ及び相関器９の出力Ｂである相互相関値をグ
ラフに表わした特性図である。FIG. 3 is a characteristic diagram that graphically represents the cross-correlation values, which are the output A of the correlator 8 and the output B of the correlator 9, with respect to the relative phase of the transmitted and received PN codes.
相対位相が０．２π、４π・・・となる位置では相関値
Ａがピークをもち、相対位相がπ、３π、５π・・・の
位置では相関値Ｂがピークをもつ。The correlation value A has a peak at positions where the relative phase is 0.2π, 4π, . . . , and the correlation value B has a peak at positions where the relative phase is π, 3π, 5π, .
第４図は本実施例の同期捕捉部１２の動作を説明するフ
ローチャートである。同期捕捉を開始すると、ステップ
２０でクロック発生器１１を制御して、受信側クロック
速度を送信側クロック速度から変化させ、ステップ２１
でスライディングサーチ位相の保持値及び、相互相関ピ
ークの保持値をクリアする。次に、ステップ２２で相関
器８及び相関器９により、受信信号とＰＮ符号の相互相
関値ＢをＰＮ符号の同期毎に求める。次に、ステップ２
３でこの相関値Ｂの大きさを判定し、相関値Ｂがピーク
保持値よりも大きけれは、ステップ２４でこれを保持し
てサーチ位相の保持値をクリアしてステップ２５に進み
、また相関値Ｂがピーク保持値より小さければステップ
２５に進む。FIG. 4 is a flowchart illustrating the operation of the synchronization acquisition section 12 of this embodiment. When synchronization acquisition is started, the clock generator 11 is controlled in step 20 to change the receiving side clock speed from the transmitting side clock speed, and step 21
Clear the held value of the sliding search phase and the held value of the cross-correlation peak. Next, in step 22, a cross-correlation value B between the received signal and the PN code is obtained by the correlator 8 and the correlator 9 every time the PN code is synchronized. Next, step 2
In step 3, the magnitude of this correlation value B is determined, and if the correlation value B is larger than the peak holding value, it is held in step 24, the holding value of the search phase is cleared, and the process proceeds to step 25, and the correlation value is If B is smaller than the peak retention value, the process proceeds to step 25.
ステップ２５ては、サーチ位相の保持値が受信側の２つ
のＰＮ符号の位相差φに一致するかどうかを〒１１定し
、これが一致すれば、ステップ２６に進み相関値Ａのピ
ーク判定を行なう。また、サーチ位相の保持値が一致し
ない場合は、ステップ２１に戻り、相互相関をＰＮ符号
の次の周期について求め、これをくり返す。ステップ２
６で相関値Ａのピークが判定されれば、ステップ２７に
進み受信側クロック速度を送信側クロック速度に一致さ
せ、同期捕捉を終了する。In step 25, it is determined whether the held value of the search phase matches the phase difference φ between the two PN codes on the receiving side. If they match, the process proceeds to step 26 to determine the peak of the correlation value A. . Furthermore, if the held values of the search phases do not match, the process returns to step 21, the cross-correlation is calculated for the next cycle of the PN code, and this process is repeated. Step 2
If the peak of the correlation value A is determined in step 6, the process proceeds to step 27, where the clock speed on the receiving side is matched with the clock speed on the transmitting side, and the synchronization acquisition is completed.
第５図は本発明の第２の実施例のブロック図である。Ｐ
Ｎ符号発生器］、Ｏａ、、］、Ｏｂ、１０ｃ］、 Ｏｄ
は、同一符号系列で符号位相が９０°づつ異なる４組の
ＰＮ符号と、各ＰＮ符号の周期パルスとを発生し、掛算
器１４ ａ 、 １４ ｂ 、 １４ ｃ１４ｄは
端子１３からの受信信号とＰＮ符号との積を出力し、積
分器１５ａ、１５ｂ、１５ｃ］５ｄは、受信信号とＰＮ
符号との積を、ＰＮ符号の１周期に渡って積分すること
により、受信信号とＰＮ符号との相互相関値を出力する
。同期捕捉制御部１２は、各積分器１ ’５ ａ〜’１
．５ ｄの各相互相関値のピークを検出することにより
、クロック発生器１１のクロック速度とリセツ１へ回路
］６とを制御する。クロック発生器１］はＰＮ符号用ク
ロックを供給し、リセット回路１６は、４つのＰＮ符号
周期パルスを選択し、ＰＮ符号発生器１０ａ〜１０ ｃ
ｉをリセッ１〜することにより、Ｐ Ｎ符号系列を初期
化する。FIG. 5 is a block diagram of a second embodiment of the invention. P
N code generator], Oa, ], Ob, 10c], Od
generates four sets of PN codes with the same code sequence but different code phases by 90° and a periodic pulse of each PN code, and multipliers 14a, 14b, 14c14d combine the received signal from the terminal 13 and the PN code. The integrators 15a, 15b, 15c]5d output the product of the received signal and the PN
By integrating the product with the code over one cycle of the PN code, a cross-correlation value between the received signal and the PN code is output. The synchronization acquisition control unit 12 controls each integrator 1 '5 a to '1
．． By detecting the peak of each cross-correlation value of 5d, the clock speed of the clock generator 11 and the reset circuit 16 are controlled. The clock generator 1] supplies a clock for the PN code, and the reset circuit 16 selects four PN code period pulses, and the PN code generators 10a to 10c
By resetting i from 1 to 1, the PN code sequence is initialized.
この実施例では、掛算器１４と積分器１５とにより構成
する４組の相関器により、スライティングサーチを行な
っており、同期捕捉に要する時間を短かくできるという
利点がある。すなわち、各を同期捕捉制御部１２が検出
するとクロック発生器１１を制御して受信側クロック速
度を送信側クロック速度に一致させ同期捕捉を終了する
。In this embodiment, the slitting search is performed by four sets of correlators constituted by a multiplier 14 and an integrator 15, and there is an advantage that the time required for synchronization acquisition can be shortened. That is, when the synchronization acquisition control unit 12 detects each, it controls the clock generator 11 to make the reception side clock speed match the transmission side clock speed and completes the synchronization acquisition.
この時、相互相関の積分はＦ’ Ｎ ｉ号発生器１０ａ
の周期パルスに同期しているので、これ以外のＰＮ符号
との相互相関ピークで同期捕捉した場合には、リセット
回路１６により、同期捕捉したＰＮ符号周期パルスによ
り全てのＰＮ符号発生器１０ａ〜］○ｄをリセットする
ことにより、送信側ＰＮ符号と同期させている。At this time, the integral of the cross-correlation is F' N i number generator 10a
Therefore, if synchronization is acquired at the cross-correlation peak with other PN codes, the reset circuit 16 causes all the PN code generators 10a to 10a to be synchronized with the synchronized PN code period pulse. By resetting ○d, it is synchronized with the transmitting side PN code.
以上説明したように、本発明は、スペクトラム拡散通信
の同期捕捉の判定を受信信号とそれぞれ異なる符号位相
の複数のＰＮ系列との相互相関のピークを検出して行な
うことにより、伝送路のノイズによって、相互相関値が
低下しても、正しく同期捕捉を行なうことができる効果
がある。また、相互相関が真の同期待以外の相対位相点
で疑似ピーク特性を生じる場合にも、相対位相の３６０
° （２π）に渡って真のピーク位相を検出しているの
で、誤って疑似ピークに同期してしまうことがなく、更
に、相対位相の３６０６の範囲を複数の相関器によって
区分を分割し、同時にピーク検出を行なっているので、
同期捕捉に要する時間を短縮できるという効果がある。As explained above, the present invention detects the peak of the cross-correlation between the received signal and a plurality of PN sequences with different code phases to determine synchronization acquisition in spread spectrum communication. , even if the cross-correlation value decreases, there is an effect that synchronization acquisition can be performed correctly. Also, if the cross-correlation produces a pseudo peak characteristic at a relative phase point other than the true same expectation, 360% of the relative phase
Since the true peak phase is detected over (2π), there is no possibility of accidentally synchronizing with a pseudo peak. Since peak detection is performed at the same time,
This has the effect of reducing the time required for synchronization acquisition.
第１図は本発明の一実施例を適用したスペクトラム拡散
受信機の同期捕捉部のブロック図、第２図は第１図のス
ペクトラム拡散通信におりる変復調部のブロック図、第
３図は第２図の送受信ＰＮ符号の相対位相に対する受信
側復調部の相互相関値を示す特性図、第４図は第１図の
同期捕捉制御部の動作フロー図、第５図は本発明の第２
の実施例であるスペク（・ラム拡散受信機の同期捕捉部
のブロック図である。
１・・・送信機、２・・・受信機、３・・変調器、４・
・復調器、５，６・・・ＰＮ符号発生器、７・・伝送路
、８．９−・・相関器、１０．１０ａ、１０ｂ、１０Ｃ
，１０ｄ・・・ＰＮ符号発生器、１１・・・クロツタ発
生器、１２・・・同期捕捉制御部、］３・・受信信号入
力端子、１．４ａ、１４ｂ、１４ｃ、１４ｄ−・掛算器
、１５ａ、１５ｂ、 コ５ｃ、］、５ｄ・−積分器、
１６・・・リセット回路、２０〜２７・処理ステツーつ
プ。
興シリFIG. 1 is a block diagram of a synchronization acquisition section of a spread spectrum receiver to which an embodiment of the present invention is applied, FIG. 2 is a block diagram of a modulation/demodulation section involved in spread spectrum communication in FIG. FIG. 2 is a characteristic diagram showing the cross-correlation value of the receiving side demodulator with respect to the relative phase of the transmitting/receiving PN code, FIG. 4 is an operation flow diagram of the synchronization acquisition control section of FIG. 1, and FIG.
1 is a block diagram of a synchronization acquisition unit of a spectrum spread receiver which is an embodiment of 1. Transmitter, 2. Receiver, 3. Modulator, 4.
・Demodulator, 5, 6...PN code generator, 7...Transmission line, 8.9-...Correlator, 10.10a, 10b, 10C
, 10d...PN code generator, 11... Crochet generator, 12... Synchronization acquisition control unit, ]3... Received signal input terminal, 1.4a, 14b, 14c, 14d-- Multiplier, 15a, 15b, 5c, ], 5d - integrator,
16...Reset circuit, 20-27. Processing steps. Kosiri
Claims (1)
ダム（以下ＰＮという）符号をクロックに同期して発生
するＰＮ符号発生手段と、前記複数のＰＮ符号と受信信
号との相互相関をそれぞれ求める複数の相関手段と、前
記受信信号のクロック速度を送信側のクロックと異なら
せることにより、送受信機のＰＮ符号間の相対位置を変
化させる位相可変手段と、前記位相を可変させて相互相
関のピークを検出するピーク検出手段と、このピーク検
出手段が一方の相互相関のピークを検出した時の符号位
相差に等しい送受信機のＰＮ符号の相対位相をずらして
他方の相互相関のピークを検出した時、前記クロック速
度を送信側と一致させるクロック速度制御手段とを含む
ことを特徴とするスペクトラム拡散通信の同期捕捉方式
。 ２、符号位相の異なる複数のＰＮ符号が２系列または４
系列である請求項１記載のスペクトラム拡散通信の同期
捕捉方式。[Claims] 1. A PN code generating means for generating a plurality of pseudorandom (hereinafter referred to as PN) codes having the same code sequence and different code phases in synchronization with a clock, and a method for generating a plurality of pseudorandom (hereinafter referred to as PN) codes having the same code sequence and different code phases; a plurality of correlation means for respectively calculating cross-correlation of the signals; a phase variable means for changing the relative position between the PN codes of the transmitter and receiver by making the clock speed of the received signal different from the clock on the transmitting side; and the phase variable means for varying the phase. a peak detection means for detecting the peak of the cross-correlation by shifting the relative phase of the PN code of the transmitter/receiver equal to the code phase difference when the peak detection means detects the peak of the other cross-correlation; 1. A synchronous acquisition method for spread spectrum communication, comprising: clock speed control means for making the clock speed match that of a transmitting side when a peak of the clock speed is detected. 2. Two or four sequences of multiple PN codes with different code phases
2. The synchronization acquisition method for spread spectrum communication according to claim 1, wherein the synchronization acquisition method is a spread spectrum communication system.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19027790A JP2890723B2 (en) | 1990-07-18 | 1990-07-18 | Synchronous acquisition method for spread spectrum communication |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19027790A JP2890723B2 (en) | 1990-07-18 | 1990-07-18 | Synchronous acquisition method for spread spectrum communication |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0479438A true JPH0479438A (en) | 1992-03-12 |
| JP2890723B2 JP2890723B2 (en) | 1999-05-17 |
Family
ID=16255486
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP19027790A Expired - Lifetime JP2890723B2 (en) | 1990-07-18 | 1990-07-18 | Synchronous acquisition method for spread spectrum communication |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2890723B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5859875A (en) * | 1996-10-01 | 1999-01-12 | Uniden Corporation | Transmitter, receiver, communication system, and communication method employing spread spectrum communication technique |
| WO1999059280A1 (en) * | 1998-05-14 | 1999-11-18 | Masahichi Kishi | Code division multiple access (cdma) transmission system |
| US8265126B2 (en) | 2008-02-20 | 2012-09-11 | Denso Corporation | Receiving device for spread spectrum communication |
-
1990
- 1990-07-18 JP JP19027790A patent/JP2890723B2/en not_active Expired - Lifetime
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5859875A (en) * | 1996-10-01 | 1999-01-12 | Uniden Corporation | Transmitter, receiver, communication system, and communication method employing spread spectrum communication technique |
| WO1999059280A1 (en) * | 1998-05-14 | 1999-11-18 | Masahichi Kishi | Code division multiple access (cdma) transmission system |
| US6888813B1 (en) | 1998-05-14 | 2005-05-03 | Masahichi Kishi | Code division multiple access (CDMA) transmission system |
| US8265126B2 (en) | 2008-02-20 | 2012-09-11 | Denso Corporation | Receiving device for spread spectrum communication |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2890723B2 (en) | 1999-05-17 |
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