JPS632383B2 - - Google Patents
Info
- Publication number
- JPS632383B2 JPS632383B2 JP2506381A JP2506381A JPS632383B2 JP S632383 B2 JPS632383 B2 JP S632383B2 JP 2506381 A JP2506381 A JP 2506381A JP 2506381 A JP2506381 A JP 2506381A JP S632383 B2 JPS632383 B2 JP S632383B2
- Authority
- JP
- Japan
- Prior art keywords
- frequency
- master station
- station
- slave
- slave station
- 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
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Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/10—Frequency-modulated carrier systems, i.e. using frequency-shift keying
- H04L27/16—Frequency regulation arrangements
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/0014—Carrier regulation
- H04L2027/0083—Signalling arrangements
- H04L2027/0089—In-band signals
- H04L2027/0093—Intermittant signals
- H04L2027/0095—Intermittant signals in a preamble or similar structure
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Time-Division Multiplex Systems (AREA)
- Mobile Radio Communication Systems (AREA)
Description
【発明の詳細な説明】
本発明は散在する複数の子局とこれらに共通の
１つの親局とで形成される時分割多方向通信網に
おける子局の送信周波数を安定化する通信方式に
関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a communication method for stabilizing the transmission frequency of a slave station in a time-division multidirectional communication network formed by a plurality of scattered slave stations and one master station common to them. It is.
従来の時分割多方向通信方式の１例を第１図に
示す。 An example of a conventional time division multidirectional communication system is shown in FIG.
すなわち、親局１から多重化されたPCM信号
を多方向に一斉に発射し、各子局(1)２1〜（ｎ）
２oでは親局から送信されたPCM信号のうちの自
局割当分の時分割信号を取り出して受信する。各
子局から親局１に向け信号が自局に割当てられた
時間帯においてまたは信号伝播遅延時間について
修正を加えて送信が行なわれ、親局１には各子局
からの信号が送信順に到着するようにする。すな
わち、親局においては各子局からの受信信号が
各々重ならず１，２，…，ｎと時間軸上に整然と
配列される。 In other words, multiplexed PCM signals are emitted from the master station 1 in multiple directions all at once, and each slave station (1)2 1 to (n)
2 o extracts and receives the time-division signal allocated to the local station from among the PCM signals transmitted from the master station. Signals from each slave station to master station 1 are transmitted during the time slot assigned to the own station or with corrections made to the signal propagation delay time, and signals from each slave station arrive at master station 1 in the order in which they were sent. I'll do what I do. That is, in the master station, the received signals from the respective slave stations are arranged neatly on the time axis as 1, 2, . . . , n without overlapping each other.
この場合、親局１と子局２1〜２oとの間でたと
えば20GHzのようなマイクロ波による通信方式を
考えると、親局からは１周波数fTが一斉に発射す
る場合、各子局が独立した発振源を有して周波数
fRで送信する。そして、親局１では１つの復調器
で各子局の信号を復調するため、各子局の周波数
に図のように△f1、△f2、△foのようにずれを生
じ、第２図に示すように、周波数fn→fn′の場合
出力電圧がVn→Vn′となりずれ誤りが増加して
しまう。これは各子局の送信周波数を決める発振
源として空胴共振器を用いているため、周波数安
定度が十分でなく周波数ずれが生じるものであ
る。この送信周波数安定度を高めるため水晶発振
器等を用いることも行なわれているが、安定度を
高めると変調感度が落ちるという欠点があつた。 In this case, considering a communication method using microwaves such as 20 GHz between the master station 1 and the slave stations 2 1 to 2 o , if one frequency f T is emitted from the master station all at once, each slave station has an independent oscillation source and the frequency
f Send with R. Since the master station 1 demodulates the signal of each slave station with one demodulator, the frequency of each slave station is shifted as △f 1 , △f 2 , △ fo as shown in the figure. As shown in FIG. 2, when the frequency f n →f n ', the output voltage becomes V n →V n ', and the deviation error increases. Since this uses a cavity resonator as an oscillation source that determines the transmission frequency of each slave station, frequency stability is insufficient and frequency deviation occurs. Crystal oscillators and the like have been used to improve the stability of the transmission frequency, but this has the disadvantage that increasing the stability reduces modulation sensitivity.
一方、PCM信号を送信するため符号変調する
方式としては、振幅変調方式、パルスシフトキイ
ーング（PSK）変調方式、周波数シフトキイー
ング（FSK）変調方式等が考えられる。これら
のうち、最初の振幅変調方式は周知のように雑音
に対し問題があり、次のPSK方式では各子局の
送信周波数の基準として親局１からのPSK信号
から搬送波を抽出して用いることは容易である
が、周波数が不安定であるため位相同期確立させ
るのがバースト状の信号の場合困難である。その
ため本発明には用いられない。FSK方式では周
知のように、周波数差のみでキイーングが行なわ
れ最も簡単な変調方式であるが、このままでは搬
送波を直接抽出することができず、正負方向の周
波数差の平均値から求められている。この場合複
雑な構成を要しかつ時間遅れを生じる。そこで
FSK変調方式を用いてしかも搬送波を直接抽出
できることが望ましい。 On the other hand, possible methods of code modulation for transmitting PCM signals include amplitude modulation, pulse shift keying (PSK) modulation, and frequency shift keying (FSK) modulation. Among these, the first amplitude modulation method has a problem with noise as is well known, and the next PSK method extracts a carrier wave from the PSK signal from the master station 1 and uses it as a reference for the transmission frequency of each slave station. However, it is difficult to establish phase synchronization for burst-like signals because the frequency is unstable. Therefore, it is not used in the present invention. As is well known, in the FSK method, keying is performed using only the frequency difference and is the simplest modulation method, but as it is, it is not possible to directly extract the carrier wave, and it is determined from the average value of the frequency difference in the positive and negative directions. . In this case, a complicated configuration is required and a time delay occurs. Therefore
It is desirable to be able to directly extract the carrier wave using the FSK modulation method.
本発明の目的はFSK変調方式を用い簡単な方
法で搬送波を再生し子局の送信周波数を安定化す
る時分割多方向通信方式を提供することである。 An object of the present invention is to provide a time-division multidirectional communication system that uses the FSK modulation system to regenerate carrier waves in a simple manner and stabilize the transmission frequency of slave stations.
前記目的を達成するため、本発明の時分割多方
向通信方式は周波数シフトキイーング（FSK）
変調方式を用いて複数の子局と１つの親局とで多
方向通信網を形成し、親局は各子局向けの信号を
時分割により各方面に一斉に送信し、各子局は親
局クロツクに同期して、自局割当時間帯に親局に
向けて送信を行なう時分割多方向通信方式におい
て、親局から子局向けの信号中に無変調搬送波を
挿入するとともに、子局の送信時親局からの無変
調搬送波を抽出する手段と、該搬送周波数を基準
周波数として子局送信周波数を安定化する手段と
を具えたことを特徴とするものである。 In order to achieve the above object, the time division multidirectional communication system of the present invention uses frequency shift keying (FSK).
A multidirectional communication network is formed between multiple slave stations and one master station using a modulation method, and the master station transmits signals for each slave station simultaneously in all directions by time division. In a time-division multidirectional communication system that synchronizes with the station clock and transmits to the master station during its own allocated time slot, an unmodulated carrier wave is inserted into the signal from the master station to the slave station, and the The present invention is characterized by comprising means for extracting an unmodulated carrier wave from a master station during transmission, and means for stabilizing a slave station transmission frequency using the carrier frequency as a reference frequency.
以下本発明は実施例につき詳述する。 The present invention will be described in detail below with reference to examples.
第３図、第４図および第５図ａ〜ｃは従来例と
比較した本発明の原理説明図である。 FIG. 3, FIG. 4, and FIG. 5 a to c are explanatory views of the principle of the present invention in comparison with a conventional example.
第３図は従来例の構成説明図であり、子局がそ
れぞれ独立にFSK信号の発振源を具えたもので
ある。すなわち、PCM信号を変調器１１に入力
してFSK信号を出力し、これを分岐して空胴共
振器を有する周波数デイスクリミネータ１２に戻
す。そして共振周波数に同調するように制御信号
を変調器１１に与え、FSK信号の周波数を修正
して出力する。この場合前述のように各子局によ
り周波数ずれを生ずることは避けられない。 FIG. 3 is a diagram illustrating the configuration of a conventional example, in which each slave station is independently provided with an oscillation source for an FSK signal. That is, a PCM signal is input to a modulator 11 to output an FSK signal, which is branched and returned to a frequency discriminator 12 having a cavity resonator. Then, a control signal is given to the modulator 11 so as to be tuned to the resonance frequency, and the frequency of the FSK signal is corrected and output. In this case, as mentioned above, it is unavoidable that frequency deviations occur between each slave station.
第４図は本発明の原理説明図である。 FIG. 4 is a diagram explaining the principle of the present invention.
本発明では、周波数デイスクリミネータ１３と
して第３図のように空胴共振器を用いることな
く、後述するような位相同期ループを用いること
により、該ループに親局からのFSK信号を与え
て搬送波を抽出するが、前述のとおりFSK信号
から直接抽出することはできない。そこで本発明
では第５図ａ，ｂに示すように、親局からの
FSK信号１〜ｎのフレームの先頭または後部に
無変調搬送波（CAR）を挿入しておく。通常、
親局から子局へのFSK信号は逆方向の子局から
親局へのFSK信号より必要なフレームビツト数
は少ないにも拘らず、同一のフレームビツト数が
与えられ空所にはダミービツトが充当されてい
る。すなわち、第５図ｃに示すように、子局から
親局へのフレームには必ず各フレームF1〜F3の
それぞれの領域C1〜C3に補助信号ビツトが挿入
されている。従つて、とくにデータフレームを増
加する必要がない。そしてこのCARの位置は明
確であるから周波数デイスクリミネータ１３で搬
送波が検出される。これが制御器１４でたとえば
AFC回路により変調器１１を制御し、子局から
送信するFSK信号に対する基準周波数として所
定の周波数に安定化して出力する。 In the present invention, instead of using a cavity resonator as shown in FIG. 3 as the frequency discriminator 13, by using a phase-locked loop as described later, an FSK signal from a master station is applied to the loop to generate a carrier wave. However, as mentioned above, it cannot be extracted directly from the FSK signal. Therefore, in the present invention, as shown in Fig. 5a and b,
An unmodulated carrier wave (CAR) is inserted at the beginning or end of the frame of FSK signals 1 to n. usually,
Even though the FSK signal from the master station to the slave station requires fewer frame bits than the FSK signal from the slave station to the master station in the opposite direction, the same number of frame bits are given, and dummy bits are filled in the blank spaces. has been done. That is, as shown in FIG. 5c, auxiliary signal bits are always inserted into the respective areas C1 to C3 of each frame F1 to F3 in the frame from the slave station to the master station. Therefore, there is no particular need to increase the number of data frames. Since the position of this CAR is clear, the frequency discriminator 13 detects the carrier wave. This is the controller 14, for example
The modulator 11 is controlled by the AFC circuit, and is stabilized to a predetermined frequency as a reference frequency for the FSK signal transmitted from the slave station and output.
第６図ａ，ｂは上述の本発明の原理に従う実施
例説明図である。 FIGS. 6a and 6b are explanatory diagrams of an embodiment according to the principle of the present invention described above.
同図ａにおいて、第５図ａ，ｂに示した親局か
らのFSK信号を位相器（PD）１５、低域通過フ
イルタ１６および電圧制御発振器１７より成る位
相同期ループのPD１５に入力し、子局側にPCM
信号を検出するとともに、たとえば第８図で後述
するように、親局からのFSK信号の搬送波を検
出し、これをAFC回路１８に与えて変調器１１
からのFSK信号との差周波数△ｆに対応する制
御信号を変調器１１に戻して制御し、子局からの
FSK信号を所定周波数に安定化する。 In FIG. 5a, the FSK signal from the master station shown in FIGS. PCM on station side
In addition to detecting the signal, for example, as will be described later in FIG.
The control signal corresponding to the difference frequency △f with the FSK signal from the slave station is returned to the modulator 11 for control, and
Stabilizes the FSK signal to a predetermined frequency.
同図ｂは同図ａのAFC回路１８の具体回路例
である。すなわち、親局からのFSK信号より検
出した搬送波の受信周波数と、変調器１１からの
FSK信号の送信周波数とを位相器１８−１に入
れ位相差に相当する電圧を低域通過フイルタ１８
−２を通して水晶デイスクリミネータ１８−５内
の位相器１８−３に入れ、水晶発振器１８−４か
ら受信周波数と送信周波数の差の周波数△ｆに相
当する固定周波数を位相器１８−３に入れ、その
差を送信周波数制御信号として変調器１１に送
る。 Figure b shows a specific circuit example of the AFC circuit 18 shown in figure a. In other words, the reception frequency of the carrier wave detected from the FSK signal from the master station and the signal from the modulator 11 are
The transmission frequency of the FSK signal is put into the phase shifter 18-1, and the voltage corresponding to the phase difference is passed through the low-pass filter 18.
-2 to the phase shifter 18-3 in the crystal discriminator 18-5, and a fixed frequency corresponding to the frequency △f, which is the difference between the reception frequency and the transmission frequency, from the crystal oscillator 18-4 is input to the phase shifter 18-3. , the difference is sent to the modulator 11 as a transmission frequency control signal.
第７図は本発明の他の実施例の構成を示す説明
図である。 FIG. 7 is an explanatory diagram showing the configuration of another embodiment of the present invention.
同図において、親局からのFSK信号を入力す
る位相器（PD）１５、低域通過フイルタ１６お
よび電圧制御発振器（VCO）１７より成る位相
同期ループを、子局より送信するFSK信号を発
生する局部発振器として用いる。すなわち、
PCM信号を△ｆ周波数変調器２１に入力し、送
信周波数を受信周波数との差の周波数△ｆを変調
し、変調器２２でVCO１７から出力する局部発
振周波数と混合してFSK信号として子局より送
信する。 In the figure, a phase-locked loop consisting of a phase shifter (PD) 15, a low-pass filter 16, and a voltage controlled oscillator (VCO) 17, which inputs the FSK signal from the master station, generates the FSK signal to be transmitted from the slave station. Used as a local oscillator. That is,
The PCM signal is input to the △f frequency modulator 21, and the frequency △f, which is the difference between the transmitting frequency and the receiving frequency, is modulated, and the modulator 22 mixes it with the local oscillation frequency output from the VCO 17 as an FSK signal from the slave station. Send.
第８図は本発明のさらに他の実施例の構成を示
す説明図であり、親局からのFSK信号の搬送波
検出回路を示す。 FIG. 8 is an explanatory diagram showing the configuration of still another embodiment of the present invention, and shows a carrier wave detection circuit for an FSK signal from a master station.
すなわち、上述の実施例の位相器１５、低域通
過フイルタ１６、および電圧制御発振器（VCO）
１７より成る位相同基ループに対し、低域通過フ
イルタ１６とVCO１７の間に第２図ａ〜ｃから
のFSKフレームの無変調搬送波（CAR）を検出
するCAR検出器２３とこれを記憶しておくサン
プルホールド（Ｓ／Ｈ）回路２４を挿入したもの
である。 That is, the phase shifter 15, low pass filter 16, and voltage controlled oscillator (VCO) of the above-described embodiment
17, there is a CAR detector 23 between the low-pass filter 16 and the VCO 17 that detects the unmodulated carrier wave (CAR) of the FSK frame from FIG. In this example, a sample hold (S/H) circuit 24 is inserted.
以上説明したように、本発明によれば、FSK
変調方式を用いて複数の子局と１つの親局とで形
成される時分割多方向通信方式において、親局か
ら子局向けのFSK信号に無変調搬送波を挿入し
ておき、子局の送信時この無変調搬送波を抽出
し、これを基準周波数として子局送信周波数を安
定化するものである。これにより従来困難であつ
たFSK信号から容易に搬送波を再生することが
でき、多方向の子局から親局に対し誤りのないデ
ータ送出を確実に行なうことができる。 As explained above, according to the present invention, FSK
In a time-division multidirectional communication system that uses a modulation method to form multiple slave stations and one master station, an unmodulated carrier wave is inserted into the FSK signal from the master station to the slave station, and the slave station transmits This unmodulated carrier wave is then extracted and used as a reference frequency to stabilize the slave station transmission frequency. This makes it possible to easily recover a carrier wave from an FSK signal, which has been difficult in the past, and it is possible to reliably transmit error-free data from a slave station to a master station in multiple directions.
第１図、第２図は時分割多方向通信方式の一般
説明図、第３図、第４図、第５図ａ，ｂは従来例
と比較した本発明の原理説明図、第６図ａ，ｂは
本発明の実施例の構成を示す説明図、第７図、第
８図はそれぞれ本発明の他の実施例の構成を示す
説明図であり、図中、１１は変調器、１５は位相
器、１６は低域通過フイルタ、１７は電圧制御発
振器、１８はAFC回路、２１は△ｆ周波数変調
器、２２は変換器、２３はCAR検出器、２４は
サンプルホールド回路を示す。
Figures 1 and 2 are general explanatory diagrams of the time-division multidirectional communication system, Figures 3, 4, and 5 a and b are diagrams that explain the principles of the present invention in comparison with the conventional example, and Figure 6 a. , b are explanatory diagrams showing the configuration of an embodiment of the present invention, and FIGS. 7 and 8 are explanatory diagrams showing the configuration of other embodiments of the present invention, respectively. In the figure, 11 is a modulator, 15 is an explanatory diagram 16 is a low pass filter, 17 is a voltage controlled oscillator, 18 is an AFC circuit, 21 is a Δf frequency modulator, 22 is a converter, 23 is a CAR detector, and 24 is a sample and hold circuit.
Claims (1)
を用いて複数の子局と１つの親局とで多方向通信
網を形成し、親局は各子局向けの信号を時分割に
より各方向に一斉に送信し、各子局は親局クロツ
クに同期して、自局割当時間帯に親局に向けて送
信を行なう時分割多方向通信方式において、親局
から子局向けの信号中に無変調搬送波を挿入する
とともに、子局の送信時親局からの無変調搬送波
を抽出する手段と、該搬送周波数を基準周波数と
して子局送信周波数を安定化する手段とを具えた
ことを特徴とする時分割多方向通信方式。1 Using the frequency shift keying (FSK) modulation method, multiple slave stations and one master station form a multidirectional communication network, and the master station transmits signals for each slave station simultaneously in each direction by time division. In a time-division multidirectional communication system in which each slave station synchronizes with the master station's clock and transmits to the master station during its own assigned time slot, an unmodulated carrier is used in the signal from the master station to the slave stations. , a means for extracting an unmodulated carrier wave from a master station during transmission by a slave station, and a means for stabilizing a slave station transmission frequency using the carrier frequency as a reference frequency. Multidirectional communication method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2506381A JPS57140049A (en) | 1981-02-23 | 1981-02-23 | Time division multi-direction communication system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2506381A JPS57140049A (en) | 1981-02-23 | 1981-02-23 | Time division multi-direction communication system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS57140049A JPS57140049A (en) | 1982-08-30 |
| JPS632383B2 true JPS632383B2 (en) | 1988-01-19 |
Family
ID=12155453
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2506381A Granted JPS57140049A (en) | 1981-02-23 | 1981-02-23 | Time division multi-direction communication system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS57140049A (en) |
-
1981
- 1981-02-23 JP JP2506381A patent/JPS57140049A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS57140049A (en) | 1982-08-30 |
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