JPH0461534A - Store and forward simultaneous demodulator - Google Patents

Store and forward simultaneous demodulator

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Publication number
JPH0461534A
JPH0461534A JP17291590A JP17291590A JPH0461534A JP H0461534 A JPH0461534 A JP H0461534A JP 17291590 A JP17291590 A JP 17291590A JP 17291590 A JP17291590 A JP 17291590A JP H0461534 A JPH0461534 A JP H0461534A
Authority
JP
Japan
Prior art keywords
signal
phase
output
time
storage circuit
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.)
Granted
Application number
JP17291590A
Other languages
Japanese (ja)
Other versions
JP2586697B2 (en
Inventor
Tomoyoshi Osawa
智喜 大澤
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NEC Corp
Original Assignee
NEC Corp
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Filing date
Publication date
Application filed by NEC Corp filed Critical NEC Corp
Priority to JP2172915A priority Critical patent/JP2586697B2/en
Publication of JPH0461534A publication Critical patent/JPH0461534A/en
Application granted granted Critical
Publication of JP2586697B2 publication Critical patent/JP2586697B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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  • Filters That Use Time-Delay Elements (AREA)
  • Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)

Abstract

PURPOSE:To demodulate a signal without use of a preamble even in a burst signal having a large carrier frequency offset by outputting a reception signal of a storage circuit whose phase is rotated in the opposite order, entering the reception signal and a carrier signal to a product detector and demodulating a burst signal. CONSTITUTION:A counter 6 is counted synchronously with a data input and a switch 51 is changed over when the count reaches N, temporary switches 52, 53 are turned on to give an output of an adaptive bright line emphasizer 12 to inverse time converters 3, 4, which respectively set each output value. The data inputted from a terminal 2001 is entered in a phase modulation signal demodulator 1 and a stack memory 21 of a storage circuit 2. An output of the stack memory 21 is multiplied with an output of the inverse time converter 4 at a complex multiplier 23. When a value of the stack memory 21 is outputted to the phase modulation signal demodulator 1 in succession to the input data, a demodulation signal of the burst signal is outputted from a terminal 2002.

Description

【発明の詳細な説明】 (産業上の利用分野) 本発明は、位相変調されたバースト信号を復調する蓄積
一括復調器に関する6 (従来の技術) 従来、位相変調されたバースト信号を復調するものとし
ては、バースト信号を仮復調してメモリに蓄え、該メモ
リに蓄えた信号からデータシーゲンスによってキャリア
位相・周波数を推定して前記バースト信号を復調する蓄
積一括復調器がある。
Detailed Description of the Invention (Industrial Application Field) The present invention relates to a storage batch demodulator that demodulates a phase-modulated burst signal.6 (Prior Art) Conventionally, a device that demodulates a phase-modulated burst signal As an example, there is a storage batch demodulator which temporarily demodulates a burst signal and stores it in a memory, and demodulates the burst signal by estimating the carrier phase and frequency from the signal stored in the memory by data sequence.

この蓄積一括復調器としては、文献(並木淳治:無線短
パゲット用蓄積一括復調方式”、信学論(B ) 、 
J67−B、pp54−61(昭59−01) :電子
情報通信学会)、文献(本田輝度、小林英雄:”PSK
信号の計算的復調法に関する検討”、信字技報、C38
7−109(1987) :電子情報通信学会)、文献
(大澤智喜;”逐次回帰推定法を用いた蓄積一括復調方
式”、信学論(B−IL J72−8−1. No、 
6. pp540−512 (昭64−06) >等に
記載されているものがあり、これらは全て、バースト全
体に渡り8%なキャリア位相・周波数を求めるものであ
った。
This storage batch demodulator is described in the literature (Junji Namiki: "Storage batch demodulation method for wireless short paget", IEICE theory (B),
J67-B, pp54-61 (Sho 59-01: Institute of Electronics, Information and Communication Engineers), literature (Honda Luminance, Kobayashi Hideo: “PSK
“Study on computational demodulation of signals”, Shinji Giho, C38
7-109 (1987): Institute of Electronics, Information and Communication Engineers), Literature (Tomoyoshi Osawa; “Accumulation batch demodulation method using successive regression estimation method”, IEICE theory (B-IL J72-8-1. No.
6. pp. 540-512 (Sho 64-06)>, etc., and all of these methods seek a carrier phase and frequency of 8% over the entire burst.

また、逐次復調技術を用いた蓄積一括復調器としては、
文献(大澤智喜、並木漂泊;”プリアンプルレス復調方
式”昭59信学総全大、2395 :電子情報通信学会
)に示されるようにスイッチバック方式を用いたものが
ある。しかしながら、このスイッチバック方式の蓄積一
括復調器はPLLを用いたものであり、搬送波周波数オ
フセットが大きくなると引き込み時間が長くなって一往
復では位相引き込み、信号復調を行うことができなくな
っていた。
In addition, as a storage batch demodulator using successive demodulation technology,
There is a method using the switchback method as shown in the literature (Tomoyoshi Osawa, Norihari Namiki, "Preambleless demodulation method", IEICE Sozen University, 1982, 2395: Institute of Electronics, Information and Communication Engineers). However, this switchback storage batch demodulator uses a PLL, and as the carrier frequency offset increases, the pull-in time becomes longer, making it impossible to pull in the phase and demodulate the signal in one round trip.

(発明が解決しようとする課題) 上述した従来の蓄積一括復調器では、低C速度の移動体
衛星通信のような搬送波周波数オフセットが大きく、か
つフェーディング等による時間的周波数変動がある場合
、復調特性が大きく劣化するという間趙がある。また、
スイッチバック方式を用いる蓄積一括復調器は時間的周
波数変動を追従できるが、搬送波周波数オフセットの値
が大きい場合、収束しないという問題がある。そこで本
発明の目的は、以上の2つの問題点を同時に解決するこ
とにある。
(Problem to be Solved by the Invention) In the conventional storage batch demodulator described above, when the carrier wave frequency offset is large and there is temporal frequency fluctuation due to fading etc., as in mobile satellite communication with low C speed, demodulation is difficult. There is a time when the characteristics are greatly deteriorated. Also,
Although the storage batch demodulator using the switchback method can track temporal frequency fluctuations, there is a problem in that it does not converge when the value of the carrier frequency offset is large. Therefore, an object of the present invention is to simultaneously solve the above two problems.

(課題を解決するための手段) 本発明の蓄積一括復調器は、 ある一定時間における位相変調されたバースト信号の受
信信号を記憶する記憶回路と、該記憶回路が記憶する前
記受信信号を同時に入力して当該受信信号の周波数をあ
る整数倍に高める周波数逓倍器と、トランスバーサルフ
ィルタでなり前記周波数逓倍器の出力信号から搬送波成
分を抽出する適応輝線強調器と、前記搬送波成分から前
記受信信号の搬送波信号を再生して出力する周波数分周
器と、乗積検波器と、前記一定時間が経過した時点に前
記適応輝線強調器から出力される前記搬送波成分の位相
を用いて前記適応輝線強調器のトランスバーサルフィル
タのタップデータを位相回転させる第1の逆時間変換器
と、前記一定時間が経過した時点に前記適応輝線強調器
から出力される前記搬送波成分の位相を用いて前記記憶
回路に記憶してある前記受信信号を位相回転させる第2
の逆時間変換器とから構成され、前記一定時間が経過し
た時点に位相回転された前記記憶回路の前記受信信号を
逆順で出力し、当該位相回転された前記受信信号と前記
搬送波信号とを前記乗積検波器に入力して前記バースト
信号を復調することを特徴とする。
(Means for Solving the Problems) The storage batch demodulator of the present invention includes a storage circuit that stores a received signal of a phase-modulated burst signal over a certain period of time, and the received signal stored in the storage circuit is input simultaneously. a frequency multiplier that increases the frequency of the received signal by a certain integer multiple; an adaptive bright line enhancer that is a transversal filter and extracts a carrier component from the output signal of the frequency multiplier; a frequency divider that reproduces and outputs a carrier signal, a product detector, and the adaptive bright line enhancer using the phase of the carrier component output from the adaptive bright line enhancer at the time when the certain period of time has elapsed. a first inverse time converter that rotates the phase of the tap data of the transversal filter; and a phase of the carrier component outputted from the adaptive bright line enhancer at the time when the predetermined time has elapsed is used to store the phase in the storage circuit. A second step for rotating the phase of the received signal.
and a reverse time converter, which outputs the phase-rotated received signal of the storage circuit in reverse order when the certain period of time has elapsed, and outputs the phase-rotated received signal and the carrier wave signal to the It is characterized in that the burst signal is demodulated by inputting it to a product detector.

(作用) 第1図は本発明の蓄積一括復調器の構成を示す図である
。タロツク同期がとれておりアイの開いたボー間隔のバ
ースト信号である受信信号r<i>は、端子2001か
ら入力して記憶回路2に格納されるとともに、位相変調
信号復調器1にも入力する。位相変調信号復調器1は、
周波数逓倍器11、適応輝線強調器12、周波数分周器
13、乗積検波器14とから構成されている0周波数逓
倍器11はM相位相変調されたバースト信号の受信信号
r(i)に対して、 x (t ) = r (i ) ’        
−−−(1)の操作を行う。この位相変調信号復調器1
は適応輝線強調器を用いた復調器を指す。ここで、適応
輝線強調器12は第3図に示すように、相関分離器12
1、トランスバーサルフィルタ122、加算器123、
係数演算器124とから構成される。
(Function) FIG. 1 is a diagram showing the configuration of a collective storage demodulator of the present invention. The received signal r<i>, which is a baud interval burst signal with an open eye and which is synchronized with the tarock, is input from the terminal 2001 and stored in the memory circuit 2, and is also input to the phase modulation signal demodulator 1. . The phase modulation signal demodulator 1 is
The zero frequency multiplier 11, which is composed of a frequency multiplier 11, an adaptive bright line enhancer 12, a frequency divider 13, and a product detector 14, converts the received signal r(i) of the M-phase phase modulated burst signal into the received signal r(i). On the other hand, x (t) = r (i)'
--- Perform operation (1). This phase modulation signal demodulator 1
refers to a demodulator using an adaptive bright line enhancer. Here, the adaptive bright line enhancer 12 includes a correlation separator 12 as shown in FIG.
1, transversal filter 122, adder 123,
It is composed of a coefficient calculator 124.

受信信号の位相変化の例を第2図に示す、第2図におい
て、線201が受信信号の位相変化である。
An example of the phase change of the received signal is shown in FIG. 2. In FIG. 2, a line 201 is the phase change of the received signal.

一定の時間に受信された信号のシンボル数をN個とする
と、−点鎖線207で示されるシンボル数Nの時点にお
いて位相同期は終了している。またこのとき、トランス
バーサルフィルタ122の各タップのデータは2重線2
05で占められた部分であるとする(x(N−L)から
x(N)のデー夕;但し1−はタップの数)。このとき
適、応ff線強調器12の出力信号である搬送波成分を
y。とすると、第1の逆時間変換器3によりトランスバ
ーサルフィルタ122の各タップのデータを×(1)・
x(i)exp(−j−arg(yc))    ・・
・(2)但し、N−1<i<N 、 jは虚数、arg
()は複索数()の位相角を示す。
Assuming that the number of symbols of the signal received in a certain period of time is N, the phase synchronization ends at the point in time when the number of symbols is N, which is indicated by the - dotted chain line 207. Also, at this time, the data of each tap of the transversal filter 122 is the double line 2
05 (data from x(NL) to x(N); where 1- is the number of taps). At this time, it is appropriate to set the carrier wave component which is the output signal of the corresponding FF line enhancer 12 to y. Then, the first inverse time converter 3 converts the data of each tap of the transversal filter 122 into ×(1)・
x(i)exp(-j-arg(yc))...
・(2) However, N-1<i<N, j is an imaginary number, arg
() indicates the phase angle of the number of multiple lines ().

と設定し直す。このように逆時間変換されたデータは、
第2図の2重線2′06に値する。続いて記憶回路2に
格納されているデータ(r (1)からr (N) )
の位相変化をトランスバーサルフィルタ122の各タッ
プのデータの位相変化(2重線206)と連続にするた
めに、第2の逆時間変換器4により r(iJ =r(i)” exp(j−arg(y。)
/Hフ ・< 3 )但し、AoはAの共役複素数を示
す。
Set it again. The data transformed in this way is
This corresponds to double line 2'06 in FIG. Subsequently, the data stored in the memory circuit 2 (r (1) to r (N))
In order to make the phase change continuous with the phase change (double line 206) of the data of each tap of the transversal filter 122, the second inverse time converter 4 converts r(iJ = r(i)'' exp(j -arg(y.)
/Hfu・<3) However, Ao indicates the conjugate complex number of A.

の操作を行う、この操作により記憶回路2にあるデータ
の位相は、第2図の線202を共役複素数にすることに
より線203に変換され、続いて線204に変換される
。これらの操作によりトランスバーサルフィルタ122
の各タップのデータと記憶回路2のデータとは位相3!
!続となる。この逆時間変換操作を施した記憶器!i@
2のデータを位相変調信号復調器1内の乗積検波器14
に入力することによりバースト信号の受信信号は復調さ
れる。
By this operation, the phase of the data in the storage circuit 2 is converted to a line 203 by making the line 202 in FIG. 2 a conjugate complex number, and then converted to a line 204. Through these operations, the transversal filter 122
The data of each tap and the data of memory circuit 2 are in phase 3!
! To be continued. A memory device with this reverse time conversion operation! i@
2 data to the product detector 14 in the phase modulation signal demodulator 1.
The received signal of the burst signal is demodulated.

(実施例) 第4図に本発明をBPSK信号の復調に応用した一実施
例を示す。本発明の蓄積一括復調器は往F、(位相同期
過程)と復路(復調過程)の切り替えをカウンタ6を用
いてスイッチ51を切り替えることにより行っている。
(Embodiment) FIG. 4 shows an embodiment in which the present invention is applied to demodulation of a BPSK signal. The storage collective demodulator of the present invention performs switching between the forward path (phase locking process) and the backward path (demodulation process) by using the counter 6 and switching the switch 51.

このカウンタ6はスタートと同時にデータの入力に同期
してカウントを始め、カウント数がNになったときにス
イッチ51を切り替えるとともにテンポラリスイッチ5
253をオンして逆時間変換器3.4に適応輝線強調器
12の出力を渡し、逆時間変換器3,4はそれぞれの出
力値を設定する。端子2001より入力したデータはス
イッチ51を通り位相変調信号復調器1へ入力する。ま
たその入力データは記憶回路2のスタックメモリ21に
も入力する。位相変調信号復調器1は、自乗回路でなる
周波数逓信器11、適応輝線強調器12、周波数分周器
13、複素″#算器でなる乗積検波器14とで構成され
ている。適応輝線強調器12のトランスバーサルフィル
タ122は、通常、遅延回路1221、複素係数乗算器
1223.加算器1224で轡吠かれるが、本発明では
各タップのデータを式(2)に従って変換するから、複
素乗算器1222を挿入している。通常、複素乗算器1
222で乗算される係数はスイッチ52により係数記憶
器54の値(1+JO)に設定されている。また、本実
施例ではトランスバーサルフィルタのアルゴリズムにL
MSを用いているから、複素乗算器1227゜1228
、係数記憶器1226、遅延回路1220、複素加算器
1229を投けている。カウンタ6の値がNになったと
き、スイッチ51は51b側に切り替わる。また、スイ
ッチ53を瞬間的にいれて、適応輝線強調器12の出力
値ycを逆時間変換器3,4に引き渡す、逆時間変換器
3,4はROM (Read 0nly Henory
)でできており、それぞれ式(2)、<3)の指数部分
の演算結果を出力し続ける。スタックメモリ21の出力
は、複素共役回R22を通り、複素乗算器23で逆時間
変換器4の出力と乗算されることにより式(3)の演算
を行う、これらの操作により′i!l応輝線強調器12
のトランスバーサルフィルタの各タップのデータと、ス
タックメモリ21のデータとは位相31!続となり、位
相変調信号復調器1に入力データに続いてスタックメモ
リ21の値を出力することにより、端子2002よりバ
ースト信号の復調信号が出力される。第5図に本実施例
のスイッチのタイミングチャートを示す。
This counter 6 starts counting in synchronization with data input at the same time as the start, and when the count reaches N, the switch 51 is switched and the temporary switch 5
253 is turned on to pass the output of the adaptive bright line enhancer 12 to the inverse time converter 3.4, and the inverse time converters 3 and 4 set their respective output values. Data input from the terminal 2001 passes through the switch 51 and is input to the phase modulation signal demodulator 1. The input data is also input to the stack memory 21 of the storage circuit 2. The phase modulation signal demodulator 1 is composed of a frequency transmitter 11 which is a square circuit, an adaptive bright line emphasizer 12, a frequency divider 13, and a product detector 14 which is a complex "#" multiplier. The transversal filter 122 of the emphasizer 12 normally includes a delay circuit 1221, a complex coefficient multiplier 1223, and an adder 1224, but in the present invention, since the data of each tap is converted according to equation (2), complex multiplication is performed. A complex multiplier 1222 is inserted.Usually, a complex multiplier 1
The coefficient to be multiplied by 222 is set to the value (1+JO) in the coefficient memory 54 by the switch 52. In addition, in this embodiment, the algorithm of the transversal filter is
Since MS is used, complex multipliers 1227°1228
, a coefficient storage 1226, a delay circuit 1220, and a complex adder 1229. When the value of the counter 6 reaches N, the switch 51 is switched to the 51b side. Further, the switch 53 is turned on momentarily to transfer the output value yc of the adaptive bright line enhancer 12 to the inverse time converters 3 and 4.
) and continue to output the calculation results of the exponent parts of equations (2) and <3), respectively. The output of the stack memory 21 passes through the complex conjugate circuit R22 and is multiplied by the output of the inverse time converter 4 in the complex multiplier 23, thereby performing the calculation of equation (3). Through these operations, 'i! l Emission line enhancer 12
The data of each tap of the transversal filter and the data of the stack memory 21 have a phase of 31! By outputting the value of the stack memory 21 following the input data to the phase modulation signal demodulator 1, a demodulated signal of the burst signal is output from the terminal 2002. FIG. 5 shows a timing chart of the switch of this embodiment.

(発明の効果) 以上に説明したように、本発明によれば、搬送波周波数
オフセットの値が大きいバースト信号でもプリアンプル
を用いずに信号を復調できるという効果がある。
(Effects of the Invention) As described above, according to the present invention, even a burst signal having a large carrier frequency offset value can be demodulated without using a preamplifier.

【図面の簡単な説明】[Brief explanation of drawings]

第1図は本発明の蓄積一括復調器の構成を示す図、第2
図は本発明のスイッチバックにおける位相の連続を説明
するための図、第3図は適応輝線強調器12の構成を示
す図、第4図は本発明の一実施例を示す図、第5図は本
実施例のスイッチのタイムチャートを示す図である。 1・・・位相変調信号復調器、2・・・記憶回路、3゜
4・・・逆時間変換器、6・・・カウンタ、11・・・
周波数逓倍器、12・・・適応輝線強調器、13・・・
周波数分周器、14・・・乗積検波器、121・・・相
関分離器、122・・・トランスバーサルフィルタ、1
23゜1224.1225・・・加算器、124・・・
係数演算器、21・・・スタックメモリ、22・・・複
素共役回路、23,1222,1227.1228・・
・複素乗算器、51,52.53・・・スイッチ、54
゜1226・・・係数記憶器、1220.1221・・
・遅延回路、1223・・・複素係数乗算器、1229
・・・複素加算器。
FIG. 1 is a diagram showing the configuration of the storage collective demodulator of the present invention, and FIG.
3 is a diagram showing the configuration of the adaptive bright line enhancer 12, FIG. 4 is a diagram showing an embodiment of the invention, and FIG. FIG. 2 is a diagram showing a time chart of the switch of this embodiment. DESCRIPTION OF SYMBOLS 1... Phase modulation signal demodulator, 2... Memory circuit, 3° 4... Inverse time converter, 6... Counter, 11...
Frequency multiplier, 12...Adaptive bright line enhancer, 13...
Frequency divider, 14... Product detector, 121... Correlation separator, 122... Transversal filter, 1
23°1224.1225... Adder, 124...
Coefficient calculator, 21...Stack memory, 22...Complex conjugate circuit, 23,1222,1227.1228...
・Complex multiplier, 51, 52.53... switch, 54
゜1226... Coefficient storage, 1220.1221...
・Delay circuit, 1223... Complex coefficient multiplier, 1229
...Complex adder.

Claims (1)

【特許請求の範囲】[Claims] ある一定時間における位相変調されたバースト信号の受
信信号を記憶する記憶回路と、該記憶回路が記憶する前
記受信信号を同時に入力して当該受信信号の周波数をあ
る整数倍に高める周波数逓倍器と、トランスバーサルフ
ィルタでなり前記周波数逓倍器の出力信号から搬送波成
分を抽出する適応輝線強調器と、前記搬送波成分から前
記受信信号の搬送波信号を再生して出力する周波数分周
器と、乗積検波器と、前記一定時間が経過した時点に前
記適応輝線強調器から出力される前記搬送波成分の位相
を用いて前記適応輝線強調器のトランスバーサルフィル
タのタップデータを位相回転させる第1の逆時間変換器
と、前記一定時間が経過した時点に前記適応輝線強調器
から出力される前記搬送波成分の位相を用いて前記記憶
回路に記憶してある前記受信信号を位相回転させる第2
の逆時間変換器とから構成され、前記一定時間が経過し
た時点に位相回転された前記記憶回路の前記受信信号を
逆順で出力し、当該位相回転された前記受信信号と前記
搬送波信号とを前記乗積検波器に入力して前記バースト
信号を復調することを特徴とする蓄積一括復調器。
a storage circuit that stores a reception signal of a phase-modulated burst signal over a certain period of time; a frequency multiplier that simultaneously inputs the reception signal stored in the storage circuit and increases the frequency of the reception signal to a certain integral multiple; an adaptive bright line enhancer that is a transversal filter and extracts a carrier wave component from the output signal of the frequency multiplier; a frequency divider that reproduces and outputs a carrier wave signal of the received signal from the carrier wave component; and a product detector. and a first inverse time converter that rotates the phase of the tap data of the transversal filter of the adaptive bright line enhancer using the phase of the carrier component output from the adaptive bright line enhancer after the certain period of time has elapsed. and a second step of rotating the phase of the received signal stored in the storage circuit using the phase of the carrier component output from the adaptive bright line enhancer after the predetermined period of time has elapsed.
and a reverse time converter, which outputs the phase-rotated received signal of the storage circuit in reverse order when the certain period of time has elapsed, and outputs the phase-rotated received signal and the carrier wave signal to the 1. A collective accumulation demodulator, characterized in that the burst signal is demodulated by inputting it to a product detector.
JP2172915A 1990-06-29 1990-06-29 Storage batch demodulator Expired - Lifetime JP2586697B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2172915A JP2586697B2 (en) 1990-06-29 1990-06-29 Storage batch demodulator

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2172915A JP2586697B2 (en) 1990-06-29 1990-06-29 Storage batch demodulator

Publications (2)

Publication Number Publication Date
JPH0461534A true JPH0461534A (en) 1992-02-27
JP2586697B2 JP2586697B2 (en) 1997-03-05

Family

ID=15950709

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2172915A Expired - Lifetime JP2586697B2 (en) 1990-06-29 1990-06-29 Storage batch demodulator

Country Status (1)

Country Link
JP (1) JP2586697B2 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08251244A (en) * 1995-03-11 1996-09-27 Nec Corp Carrier regenerating circuit

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08251244A (en) * 1995-03-11 1996-09-27 Nec Corp Carrier regenerating circuit
US6125151A (en) * 1995-03-11 2000-09-26 Nec Corporation Carrier recovery circuit

Also Published As

Publication number Publication date
JP2586697B2 (en) 1997-03-05

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