JP2812278B2 - Data transmission method and data transmission device - Google Patents
Data transmission method and data transmission deviceInfo
- Publication number
- JP2812278B2 JP2812278B2 JP467696A JP467696A JP2812278B2 JP 2812278 B2 JP2812278 B2 JP 2812278B2 JP 467696 A JP467696 A JP 467696A JP 467696 A JP467696 A JP 467696A JP 2812278 B2 JP2812278 B2 JP 2812278B2
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- Prior art keywords
- transmission
- data transmission
- frequency
- signal
- data
- Prior art date
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- Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
Description
【0001】[0001]
【発明の属する技術分野】本発明はデータ伝送装置に関
し、特に伝送情報に対して予め広帯域伝送を行うスペク
トラム拡散変調方式によるデータ伝送装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data transmission apparatus, and more particularly, to a data transmission apparatus using a spread spectrum modulation method for performing wideband transmission of transmission information in advance.
【0002】[0002]
【従来の技術】従来のスペクトラム拡散変調方式は、基
本的には図4に示すような構成を採用している。同図に
おいて拡散変調器16は、送信データを広帯域のスペク
トラム拡散変調信号に変調する。拡散変調器16の出力
は送信高周波部14及び送受切換器12を介して空中線
11から電磁波として空間に輻射される。また、空間の
受信すべき電磁波を空中線11で高周波信号に変換入力
し、送受切替器12及び受信高周波部13を介して逆拡
散変調器15に印加される。逆拡散復調器15は、受信
高周波信号を拡散信号により逆拡散変調して受信データ
を復調する。2. Description of the Related Art A conventional spread spectrum modulation system basically employs a configuration as shown in FIG. In the figure, a spread modulator 16 modulates transmission data into a wideband spread spectrum modulated signal. The output of the spread modulator 16 is radiated as electromagnetic waves from the antenna 11 to space via the transmission high-frequency unit 14 and the transmission / reception switch 12. An electromagnetic wave to be received in space is converted into a high-frequency signal by the antenna 11 and applied to the despread modulator 15 via the transmission / reception switch 12 and the reception high-frequency unit 13. The despread demodulator 15 despread modulates the received high-frequency signal with the spread signal and demodulates the received data.
【0003】スペクトラム拡散変調方式は本来伝送すべ
きデータの伝送周波数帯域幅に対して、数10〜100
0倍程度の広い周波数帯域でデータ伝送を行う方式であ
り、送信側では拡散符号により周波数拡散変調するた
め、単位周波数帯域幅あたりの伝送電力密度が低く他の
通信系への混信・妨害が少なく、且つ受信側では周波数
逆拡散復調することによる鋭い相関特性のため他の通信
系からの混信・妨害等の影響が少ない特徴を有するデー
タ伝送方式である。従来のスペクトラム拡散変調方式に
よるデータ伝送装置においては、受信側即ち周波数逆拡
散復調の構成の簡略化及び高速化を図る例が存在する
が、送信側即ち周波数拡散変調については予め定められ
た広い周波数帯域幅で送信し、データ伝送を行ってい
る。[0003] Spread-spectrum modulation is based on several tens to 100 of the transmission frequency bandwidth of data to be transmitted.
This is a method of transmitting data in a wide frequency band of about 0 times. Since the transmitting side performs frequency spread modulation with a spreading code, the transmission power density per unit frequency bandwidth is low and interference / interference to other communication systems is reduced. In addition, on the receiving side, the data transmission method has a characteristic that the influence of interference and interference from other communication systems is small due to sharp correlation characteristics due to frequency despread demodulation. In a conventional data transmission apparatus using the spread spectrum modulation method, there is an example of simplifying and increasing the speed of the receiving side, that is, the structure of the frequency despread demodulation. Data is transmitted by transmitting at the bandwidth.
【0004】一方、スペクトラム拡散変調方式はCDM
(符号分割多重)方式の一種あり、同一の伝送空間即ち
周波数帯を複数の利用者(加入者)が同時に使用するこ
とを前提としている場合もある。この場合には、複数の
利用者のデータ伝送装置間で相互に干渉し合うことにな
る。On the other hand, the spread spectrum modulation system uses the CDM
There is a type of (code division multiplexing) system, which may be based on the premise that a plurality of users (subscribers) use the same transmission space, that is, the same frequency band, at the same time. In this case, the data transmission devices of a plurality of users interfere with each other.
【0005】[0005]
【発明が解決しようとする課題】従来のスペクトラム拡
散変調方式によるデータ伝送装置においては、以下の問
題点が挙げられる。The following problems are raised in the data transmission apparatus based on the conventional spread spectrum modulation method.
【0006】第1の問題点は、同一の周波数帯域を複数
の利用者(加入者)によって使用される場合には、相互
の干渉を避けることが困難である。The first problem is that when the same frequency band is used by a plurality of users (subscribers), it is difficult to avoid mutual interference.
【0007】その理由は、周波数特性の落ち込んだ周波
数帯域での電力送出は、別の利用者(装置)間にとって
周波数特性が落ち込んでいるとは限らず、干渉及び妨害
を与えることになり、結果として、相互の干渉を避ける
ことが困難となる。[0007] The reason is that the power transmission in the frequency band where the frequency characteristic is degraded does not necessarily mean that the frequency characteristic is degraded for another user (device), and causes interference and interference. As a result, it is difficult to avoid mutual interference.
【0008】第2の問題点は、振幅周波数特性が平坦で
ない伝送路を介して、データ伝送を行う場合でも、不必
要な送信電力を送出してしまい、データ伝送を盗聴しよ
うとする第3者による被探知確率を低減し、秘匿性を確
保することが困難である。[0008] The second problem is that even when data transmission is performed via a transmission line whose amplitude frequency characteristic is not flat, unnecessary transmission power is sent out, and a third party who tries to eavesdrop on data transmission. Therefore, it is difficult to reduce the probability of being detected by the system and secure confidentiality.
【0009】その理由は、周波数特性の落ち込んだ周波
数帯域での電力送出は、傍受及び盗聴等を企てる第3者
(装置間)にとって周波数特性が落ち込んでいるとは限
らず、逆に信号電力密度が大となることもあり得、傍受
及び盗聴に対して第3者による被探知確率を低減し、秘
匿性を確保することが困難となる。[0009] The reason is that the power transmission in the frequency band where the frequency characteristics are degraded does not necessarily mean that the frequency characteristics are degraded by a third party (between devices) who intends to intercept and eavesdrop, and conversely, the signal power density Can be large, and it is difficult to reduce the probability of detection by a third party for eavesdropping and eavesdropping, and to ensure confidentiality.
【0010】第3の問題点は、振幅周波数特性が平坦で
ない伝送路を介して、データ伝送を行う場合でも、不必
要な送信電力を送出してしまい装置の消費電力の低減化
が困難である。A third problem is that even when data transmission is performed via a transmission line whose amplitude frequency characteristic is not flat, unnecessary transmission power is transmitted, and it is difficult to reduce the power consumption of the device. .
【0011】その理由は、スペクトラム拡散変調方式で
は、データ伝送に本来必要な周波数帯域に対して数10
〜1000倍程度の広い周波数帯域を使用しており、一
方送信機と受信機間の伝送路の振幅周波数特性は、送信
及び受信側の空中線の利得周波数特性及び実際の伝送電
波伝搬空間で生ずるマルチパス干渉等によって電波伝搬
特性が平坦でなく、振幅特性の落ち込む周波数帯域が生
ずる。このような周波数特性に対して従来のデータ伝送
装置では伝送路の周波数特性を一様とみなし、送信して
いる。従って、周波数特性が落ち込んで受信側に十分に
到達し得ない無駄な送信電力を送出してしまい、装置の
消費電力の低減化が困難である。The reason is that, in the spread spectrum modulation method, several tens of
A wide frequency band of about 1000 times is used. On the other hand, the amplitude frequency characteristic of the transmission line between the transmitter and the receiver depends on the gain frequency characteristic of the transmitting and receiving antennas and the multiplicity generated in the actual transmission radio wave propagation space. Radio wave propagation characteristics are not flat due to path interference or the like, and a frequency band in which amplitude characteristics fall is generated. With respect to such frequency characteristics, the conventional data transmission apparatus transmits the signal while assuming that the frequency characteristics of the transmission path are uniform. Therefore, useless transmission power that cannot reach the receiving side sufficiently due to a drop in frequency characteristics is transmitted, and it is difficult to reduce the power consumption of the device.
【0012】本発明では、伝送路において、振幅周波数
特性の落ち込んだ帯域での電力送出を抑えるために、無
駄な周波数帯域での信号送出が低減出来るために、伝送
効率向上、セキュリティ向上及び装置の低消費電力化を
計る。According to the present invention, in order to suppress power transmission in a band with reduced amplitude frequency characteristics in a transmission path, it is possible to reduce signal transmission in a useless frequency band. Measure low power consumption.
【0013】[0013]
【課題を解決するための手段】本発明のデータ伝送方法
は、相互にデータを送受信するデータ伝送方法におい
て、データ伝送の初期段階に広帯域信号を伝送し前記広
帯域信号の受信により伝送路の周波数振幅特性情報を測
定して相互に伝送し、前記周波数振幅特性情報に基づき
送信信号の周波数特性及びデータ伝送速度を設定して伝
送を行うことを特徴とする。A data transmission method according to the present invention is a data transmission method for mutually transmitting and receiving data, comprising: transmitting a wideband signal at an initial stage of data transmission; Characteristic information is measured and mutually transmitted, and transmission is performed by setting a frequency characteristic and a data transmission rate of a transmission signal based on the frequency amplitude characteristic information.
【0014】また、本発明のデータ伝送装置は、相互に
データを送受信するデータ伝送装置において、初期同期
確立段階にデータ伝送装置の予め定められた周波数帯域
全体を使用して初期同期信号を相互に送信し、初期同期
信号の受信信号から周波数振幅特性を検出し、前記周波
数振幅特性の落ち込んだ周波数帯域の送信エネルギーを
低減してデータ伝送を行うことを特徴とする。In a data transmission apparatus for transmitting and receiving data to and from each other, an initial synchronization signal is mutually transmitted using an entire predetermined frequency band of the data transmission apparatus in an initial synchronization establishment stage. Transmitting, detecting a frequency amplitude characteristic from a received signal of the initial synchronization signal, and performing data transmission by reducing transmission energy in a frequency band in which the frequency amplitude characteristic has dropped.
【0015】そして、前記伝送路の周波数振幅特性が一
部落ち込んだ場合は、データ伝送速度を低減し周波数振
幅特性の落ち込んでいない周波数帯域においてデータ伝
送を行うと好適である。また、前記データ伝送装置はス
ペクトラム拡散変調によるデータ伝送を行うように構成
することができる。[0015] When the frequency amplitude characteristics of the transmission path are partially reduced, it is preferable to reduce the data transmission speed and perform data transmission in a frequency band where the frequency amplitude characteristics are not reduced. Further, the data transmission device can be configured to perform data transmission by spread spectrum modulation.
【0016】更に、本発明のデータ伝送装置は、受信信
号を受信用の可変帯域瀘波器を介して逆拡散復調器で復
調する受信系と、送信データを拡散変調器で変調し送信
用の可変帯域瀘波器を介して送信する送信系とからなる
データ伝送装置において、前記受信信号の周波数振幅特
性を検出するスペクトラム分析部(スペクトラム検出/
判定器)と、前記スペクトラム分析部から得られた周波
数振幅特性情報に基づき受信用の可変帯域瀘波器の通過
特性を受信側伝送路の特性に適合させるように制御する
とともに、前記周波数振幅特性の情報を送信信号に重畳
し、且つ送信側伝送路の周波数振幅特性の情報に基づき
送信用の可変帯域瀘波器の特性を送信側伝送路の特性に
適合させるように制御する判定制御部とを有することを
特徴とする。Further, the data transmission apparatus of the present invention has a receiving system for demodulating a received signal with a despread demodulator via a variable band pass filter for reception, and a transmitting system for modulating transmission data with a spread modulator and transmitting. In a data transmission device comprising a transmission system for transmitting via a variable bandpass filter, a spectrum analyzer (spectrum detector / spectrum) for detecting a frequency amplitude characteristic of the received signal.
And a control unit that controls the pass characteristics of the variable band pass filter for reception to match the characteristics of the transmission line on the receiving side based on the frequency amplitude characteristic information obtained from the spectrum analysis unit. A decision control unit for superimposing the information on the transmission signal and controlling the characteristics of the variable band pass filter for transmission to match the characteristics of the transmission side transmission line based on the information of the frequency amplitude characteristics of the transmission side transmission line; and It is characterized by having.
【0017】データ伝送の送受信の初期段階に送信側か
らは、予め定められた全周波数帯域にわたって初期同期
信号を送出し、受信側では判定制御部により初期同期信
号を検出し、スペクトラム検出/判定器により広帯域に
拡散された受信信号のスペクトラム分析を行い伝送路の
周波数特性情報を出力し、判定制御器へ伝送路の周波数
特性情報を入力し、可変帯域瀘波器1、可変帯域瀘波器
2及び拡散変調の中心周波数及び拡散変調速度を制御
し、受信側で設定した可変瀘波器等の諸元を送信側に伝
送することにより、伝送路の特性に適したデータ伝送を
行うことができる。At the initial stage of data transmission / reception, the transmitting side transmits an initial synchronization signal over a predetermined entire frequency band, and the receiving side detects the initial synchronization signal by a determination control unit, and a spectrum detector / determiner. Performs spectrum analysis of the received signal spread over a wide band, outputs frequency characteristic information of the transmission line, inputs the frequency characteristic information of the transmission line to the decision controller, and outputs a variable bandpass filter 1 and a variable bandpass filter 2 By controlling the center frequency and spread modulation speed of the spread modulation and transmitting the data of the variable filter and the like set on the reception side to the transmission side, data transmission suitable for the characteristics of the transmission path can be performed. .
【0018】[0018]
【発明の実施の形態】本発明のデータ伝送方式の一実施
の形態について図面を参照して、その構成及び動作につ
いて詳細に説明する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a data transmission system according to the present invention will be described in detail with reference to the drawings.
【0019】図1は本発明の一実施の形態を示すブロッ
ク図である。図1を参照すると、本実施の形態も従来の
スペクトラム拡散変調方式の基本構成の、空中線11、
送受切換器12、受信高周波部13、送信高周波部1
4、逆拡散復調器15及び拡散変調器16から成る構成
を有し、更に、スペクトラム検出/判定器17、可変帯
域瀘波器18、可変帯域瀘波器19及び判定制御器20
を有している。FIG. 1 is a block diagram showing an embodiment of the present invention. Referring to FIG. 1, the present embodiment also has the antenna 11, the basic configuration of the conventional spread spectrum modulation system.
Transmission / reception switch 12, reception high frequency unit 13, transmission high frequency unit 1
4, a despread demodulator 15 and a spread modulator 16; a spectrum detector / determiner 17; a variable bandpass filter 18; a variable bandpass filter 19;
have.
【0020】図1において、空中線11はデータ伝送装
置の高周波信号出力を電磁波として空間に輻射し、ま
た、空間の受信すべき電磁波を高周波信号に変換入力す
る。送受切換器12は空中線を送信時には送信高周波部
に受信時には受信高周波部に切り換え接続する。In FIG. 1, an antenna 11 radiates a high-frequency signal output of a data transmission device into space as an electromagnetic wave, and converts and inputs an electromagnetic wave to be received in space into a high-frequency signal. The transmission / reception switch 12 switches and connects the antenna to the transmission high-frequency unit during transmission and to the reception high-frequency unit during reception.
【0021】受信高周波部13は、空中線からの信号を
増幅して可変帯域瀘波器(1)18及びスペクトラム検
出/判定器17に出力し、送信高周波部14は、可変帯
域瀘波器(2)19の出力を増幅して空中線の送受切換
器に出力する。The receiving high frequency section 13 amplifies the signal from the antenna and outputs the amplified signal to the variable bandpass filter (1) 18 and the spectrum detecting / determining section 17, and the transmitting high frequency section 14 receives the variable bandpass filter (2). A) Amplify the output of 19 and output it to the antenna duplexer.
【0022】可変帯域瀘波器(1)18は、受信信号の
受信信号帯域幅を判定制御器20からの制御により変化
でき所定の帯域の信号を通過させる。同様に可変帯域瀘
波器(2)19は、送信信号の送信信号帯域幅を判定制
御器20からの制御により変化でき所定の帯域の信号を
通過させる。The variable bandpass filter (1) 18 can change the reception signal bandwidth of the reception signal under the control of the judgment controller 20, and passes a signal of a predetermined band. Similarly, the variable bandpass filter (2) 19 can change the transmission signal bandwidth of the transmission signal under the control of the judgment controller 20, and passes a signal of a predetermined band.
【0023】逆拡散復調器15は、受信高周波信号を拡
散信号によって逆拡散復調して広帯域なスペクトラム変
調信号から受信データ出力信号を復調出力する。また、
拡散変調器16は、送信データ入力信号を拡散信号によ
り拡散変調して広帯域なスペクトラム変調信号を出力す
る。The despread demodulator 15 despread demodulates the received high-frequency signal with a spread signal and demodulates and outputs a received data output signal from a wideband spectrum modulated signal. Also,
The spread modulator 16 spread-modulates the transmission data input signal with the spread signal and outputs a wideband spectrum modulated signal.
【0024】スペクトラム検出/判定器17は、高周波
受信部からの信号を入力し、入力信号の周波数帯域毎の
信号強度の情報を出力する。The spectrum detector / determiner 17 receives a signal from the high-frequency receiver and outputs information on the signal strength of the input signal for each frequency band.
【0025】判定制御器20は、データ伝送の初期同期
信号受信時において、前記可変帯域瀘波器(1)の通過
帯域幅をスペクトラム拡散変調の予め設定した使用周波
数帯域の全帯域となるように制御するとともに、スペク
トラム検出/判定器の出力情報によりデータ受信時の前
記可変帯域瀘波器(1)の通過帯域制御情報を出力し、
且つ前記通過帯域制御情報を送信側に伝送するためデー
タ伝送装置の送信信号に重畳する信号を出力する。The decision controller 20 sets the pass band width of the variable bandpass filter (1) to be the whole of the preset use frequency band of the spread spectrum modulation when receiving the initial synchronization signal for data transmission. Controlling, and outputting pass band control information of the variable band pass filter (1) at the time of data reception based on output information of the spectrum detector / determiner,
And outputting a signal to be superimposed on a transmission signal of the data transmission device in order to transmit the passband control information to a transmission side.
【0026】図2に本発明の一実施の形態におけるスペ
クトラム検出/判定部17、可変帯域瀘波器(1)18
及び可変帯域瀘波器(2)19の具体的構成、及び判定
制御器20との接続構成を示す。FIG. 2 shows a spectrum detection / judgment section 17 and a variable bandpass filter (1) 18 according to an embodiment of the present invention.
2 shows a specific configuration of the variable bandpass filter (2) 19 and a connection configuration with the decision controller 20.
【0027】同図において、可変帯域瀘波器18,19
及びスペクトラム検出/判定器17は、通過帯域瀘波器
(1)21、通過帯域瀘波器(2)22、通過帯域瀘波
器(3)23、通過帯域瀘波器(4)24、通過帯域瀘
波器(5)25、通過帯域瀘波器(6)26、振幅検出
器(1)27、振幅検出器(2)28、振幅検出器
(3)29、通過帯域瀘波器(7)30、通過帯域瀘波
器(8)31及び通過帯域瀘波器(9)32を有してい
る。In the figure, variable bandpass filters 18, 19
And the spectrum detector / determiner 17 includes a pass band filter (1) 21, a pass band filter (2) 22, a pass band filter (3) 23, a pass band filter (4) 24, and a pass band. Band-pass filter (5) 25, pass-band filter (6) 26, amplitude detector (1) 27, amplitude detector (2) 28, amplitude detector (3) 29, pass-band filter (7) ) 30, a pass band filter (8) 31 and a pass band filter (9) 32.
【0028】図2において、スペクトラム検出/判定器
17は、受信信号の前記全帯域を複数の帯域別に分割す
る前記複数の帯域通過瀘波器(4)〜(6)BPF
(4)〜(6)とその出力のレベルを検出する振幅検出
器(1)〜(3)DET(1)〜(3)により、受信高
周波部13からの信号の周波数帯毎の信号強度の情報を
出力する。In FIG. 2, the spectrum detector / judgment unit 17 includes a plurality of band-pass filters (4) to (6) for dividing the entire band of the received signal into a plurality of bands.
(4) to (6) and amplitude detectors (1) to (3) for detecting the level of the output. Output information.
【0029】可変帯域瀘波器18は、前記帯域と同一帯
域を前記と同様の複数の帯域別に分割する複数の帯域通
過瀘波器(1)〜(3)BPF(1)〜(3)により、
受信信号の受信帯域幅を判定制御器20からの制御によ
り変化でき所定の帯域の信号を通過させる。可変帯域瀘
波器19は、同様の帯域通過瀘波器の構成により、送信
信号の送信帯域幅を判定制御器20からの制御により変
化させ所定の帯域の信号を通過させる。The variable bandpass filter 18 is composed of a plurality of bandpass filters (1) to (3) and BPFs (1) to (3) for dividing the same band as the above band into a plurality of bands similar to the above. ,
The reception bandwidth of the reception signal can be changed under the control of the judgment controller 20, and a signal of a predetermined band is passed. The variable bandpass filter 19 changes the transmission bandwidth of the transmission signal under the control of the judgment controller 20 and transmits a signal of a predetermined band by the same bandpass filter configuration.
【0030】即ち、図2の場合、帯域通過瀘波器(1)
〜(3)、(7)〜(9)は、各々通過帯域の中心周波
数が異なり予め定められた全受信帯域の3分の1の帯域
幅を有し、判定制御器20からの帯域通過瀘波器の接続
情報により3個の帯域通過瀘波器が接続された場合には
全送受信帯域幅を通過させる周波数特性を有し、また各
帯域通過瀘波器の接続の切替えにより全体として帯域阻
止瀘波器又は可変帯域通過瀘波器として機能する。That is, in the case of FIG. 2, the band-pass filter (1)
((3), (7) 〜 (9) have different center frequencies of the passbands and have a bandwidth of one third of the predetermined reception band. When three band-pass filters are connected according to the connection information of the filters, they have a frequency characteristic of passing the entire transmission / reception bandwidth, and the whole band is rejected by switching the connection of each band-pass filter. It functions as a filter or a variable bandpass filter.
【0031】判定制御器20は、データ伝送の初期同期
信号受信時のデータ伝送初期等において前記可変帯域瀘
波器(1)18の通過帯域幅を全帯域幅を有するように
制御すると共に、スペクトラム検出/判定器17からの
検出出力である前記一定の伝送帯域の内周波数振幅特性
の落ち込み帯域等の情報に基づき、データ受信時の前記
可変帯域瀘波器1の前記落ち込み帯域を阻止する通過帯
域の制御信号を出力し、且つ前記通過帯域制御情報を相
手側のデータ伝送装置に送るため自データ伝送装置の送
信信号に重畳するための信号を拡散変調器に出力する。The decision controller 20 controls the pass bandwidth of the variable bandpass filter (1) 18 so as to have the entire bandwidth at the beginning of data transmission at the time of receiving the initial synchronization signal of data transmission, and also has a spectrum. A pass band for blocking the dip band of the variable band pass filter 1 at the time of data reception based on information such as a dip band of an internal frequency amplitude characteristic of the predetermined transmission band, which is a detection output from the detection / determination unit 17. , And a signal to be superimposed on the transmission signal of the own data transmission apparatus to send the passband control information to the data transmission apparatus of the other party, and outputs the signal to the spread modulator.
【0032】図3は本発明の一実施の形態における前記
逆拡散復調器15及び拡散変調器16の詳細構成を示す
ブロック図である。図3を参照すると、逆拡散変調器1
5及び拡散変調器16は周波数変換器(1)34、局部
発振器(1)35、平衡変調器(1)36、拡散信号発
生器(1)37、周波数変換器(2)39、局部発振器
(2)38、平衡変調器(2)41及び拡散信号発生器
(2)40を有している。FIG. 3 is a block diagram showing a detailed configuration of the despread demodulator 15 and the spread modulator 16 in one embodiment of the present invention. Referring to FIG. 3, despread modulator 1
5 and the spread modulator 16 include a frequency converter (1) 34, a local oscillator (1) 35, a balanced modulator (1) 36, a spread signal generator (1) 37, a frequency converter (2) 39, and a local oscillator ( 2) 38, a balanced modulator (2) 41, and a spread signal generator (2) 40.
【0033】図3において、可変帯域瀘波器(1)18
からの受信高周波信号は周波数変換器(1)において局
部発振器の出力により周波数変換され、更に平衡変調器
(1)36において拡散信号発生器(1)37からの拡
散信号によって逆拡散して受信データを出力する。In FIG. 3, a variable bandpass filter (1) 18
The received high-frequency signal is frequency-converted by the output of the local oscillator in the frequency converter (1), and further de-spread by the spread signal from the spread signal generator (1) 37 in the balanced modulator (1) 36 to obtain the received data. Is output.
【0034】また、前記送信データ信号は、平衡変調器
(2)41において拡散信号発生器(2)40からの拡
散信号によって拡散して変調信号を出力する。前記変調
信号は周波数変換器(2)39において局部発振器
(2)38の出力により周波数変換され高周波信号とし
て可変帯域瀘波器19に出力される。The transmission data signal is spread by the spread signal from the spread signal generator (2) 40 in the balanced modulator (2) 41 to output a modulated signal. The modulated signal is frequency-converted in the frequency converter (2) 39 by the output of the local oscillator (2) 38, and output to the variable bandpass filter 19 as a high-frequency signal.
【0035】周波数変換器34は局部発振器(1)35
の出力信号により、受信信号を逆拡散変調するため必要
な処理周波数帯域に周波数変換する。このため局部発振
器(1)35は判定制御器20により制御される。The frequency converter 34 is a local oscillator (1) 35
, The received signal is frequency-converted into a processing frequency band required for despread modulation. Therefore, the local oscillator (1) 35 is controlled by the decision controller 20.
【0036】平衡変調器36は、周波数変換器(1)3
4の出力を入力し、拡散信号発生器37の出力信号によ
り平衡変調し受信データを復調する。このため拡散信号
発生器(1)37は、判定制御器20により拡散信号の
発生信号パターン及びその発生速度の制御が行われる。
平衡変調器(2)41は、送信データ信号を入力し、拡
散信号発生器(2)40の出力信号により平衡変調す
る。このため拡散信号発生器(2)40は判定制御器2
0により発生信号パターン及び発生速度の制御がおこな
われる。The balanced modulator 36 includes a frequency converter (1) 3
4 is input and balanced modulation is performed by the output signal of the spread signal generator 37 to demodulate the received data. Therefore, in the spread signal generator (1) 37, the determination controller 20 controls the generated signal pattern of the spread signal and the generation speed thereof.
The balanced modulator (2) 41 receives the transmission data signal, and performs balanced modulation by the output signal of the spread signal generator (2) 40. For this reason, the spread signal generator (2) 40
0 controls the generated signal pattern and the generated speed.
【0037】周波数変換器(2)39は、局部発振器
(2)38の出力信号により拡散変調信号を送信周波数
帯に周波数変換する。このため局部発振器(2)39
は、判定制御器20の制御により周波数変換器(2)に
対して必要な周波数の局部発振信号を出力する。The frequency converter (2) 39 converts the frequency of the spread modulation signal into a transmission frequency band based on the output signal of the local oscillator (2) 38. Therefore, the local oscillator (2) 39
Outputs a local oscillation signal of a required frequency to the frequency converter (2) under the control of the determination controller 20.
【0038】即ち、前述のように初期同期信号受信時等
のデータ伝送の初期段階において検出した、スペクトラ
ム検出/判定器17からの通過帯域制御情報(伝送路の
周波数振幅特性)に応じて、自データ伝送装置は受信系
では受信系統の可変帯域瀘波器の特性をその落ち込み等
に合わせて阻止するように制御する。また、自データ伝
送装置の送信系では送信側の伝送路の伝送特性の落ち込
み等による通過帯域制御情報が相手データ伝送装置から
通知された場合に伝送可能な帯域において必要な伝送を
実現できるように伝送帯域幅に合わせて送信系統の可変
帯域瀘波器の特性をその落ち込みに合わせて阻止するよ
うに制御し、また、伝送可能帯域の変調信号を生成する
ため伝送速度を制御し、周波数変換器の変換周波数を制
御する。このため、判定制御器20は自データ伝送装置
の可変帯域瀘波器の特性及び局部発振器の発振周波数を
制御し、また拡散信号発生器の発生信号パターン及びそ
の発生速度を制御する。なお、相手データ伝送装置にお
いてもその判定制御器において前記と同様の制御が行な
われる。That is, according to the pass band control information (frequency amplitude characteristic of the transmission path) from the spectrum detector / determiner 17 detected at the initial stage of data transmission such as at the time of receiving the initial synchronization signal as described above. The data transmission device controls the receiving system so as to block the characteristics of the variable bandpass filter of the receiving system in accordance with the drop or the like. Also, in the transmission system of the own data transmission device, it is possible to realize necessary transmission in a transmittable band when passband control information is notified from a partner data transmission device due to a drop in transmission characteristics of a transmission path on the transmission side. The frequency converter controls the characteristics of the variable bandpass filter of the transmission system in accordance with the transmission bandwidth so as to block the characteristics in accordance with the drop, controls the transmission speed in order to generate a modulated signal in a transmittable band, To control the conversion frequency. For this purpose, the decision controller 20 controls the characteristics of the variable bandpass filter of the data transmission apparatus and the oscillation frequency of the local oscillator, and also controls the generated signal pattern of the spread signal generator and its generation speed. It should be noted that the same control as described above is performed by the determination controller in the partner data transmission device.
【0039】図1、図3において受信データが判定制御
器20へ供給される信号ラインは、自データ伝送装置
(送信系)から相手装置(受信系)に向けた伝送路に関
して相手データ伝送装置(送信系)から受けた前記通過
帯域制御情報を判定制御器20へ取り入れるラインであ
る。また、同図において送信データが判定制御器20へ
供給される信号ラインは、データ伝送のスタート情報、
初期同期情報及び拡散符号の発生に必要な送信データの
データ速度等の情報を取り入れるラインである。In FIGS. 1 and 3, the signal line through which the received data is supplied to the decision controller 20 is connected to the transmission line from the own data transmission device (transmission system) to the other device (reception system). This is a line for taking the passband control information received from the transmission system) into the decision controller 20. Also, in the figure, the signal line on which the transmission data is supplied to the determination controller 20 is data transmission start information,
This line takes in information such as initial synchronization information and the data rate of transmission data necessary for generating a spreading code.
【0040】以上、本発明の前記実施の形態において
は、スペクトラム検出/判定器17は、受信信号に基づ
き本来のデータ伝送に必要な帯域を複数の帯域に分割し
てその周波数振幅特性の落ち込み等の周波数振幅特性を
検出し、判定制御器20は、前記情報を相手側データ伝
送装置に伝送し相手送信系統の送信帯域等の制御等に利
用するとともに、相手データ伝送装置から同様の情報を
取得して自データ伝送装置の受信系の通過帯域を制御
し、また、送信系統の可変帯域瀘波器の周波数特性等を
制御するようにしている。As described above, in the embodiment of the present invention, the spectrum detector / determiner 17 divides the band necessary for the original data transmission into a plurality of bands based on the received signal and reduces the frequency amplitude characteristics. The decision controller 20 transmits the information to the partner data transmission device and uses the information to control the transmission band of the partner transmission system, etc., and obtains the same information from the partner data transmission device. Thus, the pass band of the receiving system of the own data transmission apparatus is controlled, and the frequency characteristics and the like of the variable band pass filter of the transmitting system are controlled.
【0041】このため本発明によれば、データ伝送の前
記送受信の初期段階等に、送信側から予め定められた全
周波数帯で初期同期信号を送出し、受信側では前記初期
同期信号の検出とともに広帯域に拡散された受信信号の
スペクトラム分析を行い、伝送帯域幅及び中心周波数及
び伝送速度の諸元を伝送路の状態に応じ最適に設定する
ことができる。Therefore, according to the present invention, at the initial stage of the transmission / reception of data transmission, the transmitting side transmits an initial synchronization signal in all predetermined frequency bands, and the receiving side detects the initial synchronization signal together with the detection of the initial synchronization signal. The spectrum analysis of the received signal spread over a wide band is performed, and the specifications of the transmission bandwidth, the center frequency, and the transmission speed can be optimally set according to the state of the transmission path.
【0042】[0042]
【発明の効果】本発明のデータ伝送方法及びその装置に
よれば、第1の効果として、データ伝送の品質向上が図
れる。According to the data transmission method and apparatus of the present invention, as a first effect, the quality of data transmission can be improved.
【0043】その理由は、データ伝送において、不必要
な帯域の電力の送出が無くなり、共通の周波数帯域を使
用する場合においても、データ装置間相互の干渉が低減
するためである。The reason for this is that unnecessary transmission of power in a band is eliminated in data transmission, and interference between data devices is reduced even when a common frequency band is used.
【0044】第2の効果として、データ伝送における被
探知確率が減少し、通信の秘匿性が向上する。As a second effect, the probability of being detected in data transmission is reduced, and confidentiality of communication is improved.
【0045】その理由は、データ伝送において、不必要
な電力の送出が無くなり、第3者による盗聴及び傍受が
困難になるためである。The reason is that unnecessary transmission of power is eliminated in data transmission, which makes it difficult for a third party to eavesdrop and intercept.
【0046】第3の効果として、データ伝送装置の低消
費電力化が実現できる。As a third effect, the power consumption of the data transmission device can be reduced.
【0047】その理由は、伝送路の振幅周波数特性が部
分的に落ち込んでいる場合において無駄となる送信電力
を低減できるためである。The reason is that it is possible to reduce useless transmission power when the amplitude frequency characteristic of the transmission path is partially reduced.
【図1】本発明の一実施の形態を示すブロック図であ
る。FIG. 1 is a block diagram showing an embodiment of the present invention.
【図2】本発明の一実施の形態のスペクトラム検出/判
定器、可変帯域瀘波器(1)及び可変帯域瀘波器(2)
の詳細を示すブロック図である。FIG. 2 shows a spectrum detector / determiner, a variable bandpass filter (1) and a variable bandpass filter (2) according to an embodiment of the present invention.
FIG. 4 is a block diagram showing the details of.
【図3】本発明の一実施の形態の逆拡散復調器15及び
拡散変調器16の詳細を示すブロック図である。FIG. 3 is a block diagram illustrating details of a despread demodulator 15 and a spread modulator 16 according to an embodiment of the present invention.
【図4】従来のデータ伝送方式の一例を示すブロック図
である。FIG. 4 is a block diagram showing an example of a conventional data transmission system.
11 空中線 12 送受切換器 13 受信高周波部 14 送信高周波部 15 逆拡散復調器 16 拡散変調器 17 スペクトラム検出/判定器 18 可変帯域瀘波器1 19 可変帯域瀘波器2 20 判定制御器 21 帯域通過瀘波器(1) 22 帯域通過瀘波器(2) 23 帯域通過瀘波器(3) 24 帯域通過瀘波器(4) 25 帯域通過瀘波器(5) 26 帯域通過瀘波器(6) 27 振幅検出器(1) 28 振幅検出器(2) 29 振幅検出器(3) 30 帯域通過瀘波器(7) 31 帯域通過瀘波器(8) 32 帯域通過瀘波器(9) 34 周波数変換器(1) 35 局部発振器(1) 36 平衡変調器(1) 37 拡散信号発生器(1) 38 周波数変換器(2) 39 局部発振器(2) 40 平衡変調器(2) 41 拡散信号発生器(2) REFERENCE SIGNS LIST 11 antenna 12 transmission / reception switch 13 reception high frequency unit 14 transmission high frequency unit 15 despread demodulator 16 spread modulator 17 spectrum detector / determiner 18 variable bandpass filter 1 19 variable bandpass filter 2 20 decision controller 21 band pass Filter (1) 22 Band-pass filter (2) 23 Band-pass filter (3) 24 Band-pass filter (4) 25 Band-pass filter (5) 26 Band-pass filter (6) 27) Amplitude detector (1) 28 Amplitude detector (2) 29 Amplitude detector (3) 30 Band-pass filter (7) 31 Band-pass filter (8) 32 Band-pass filter (9) 34 Frequency converter (1) 35 Local oscillator (1) 36 Balanced modulator (1) 37 Spread signal generator (1) 38 Frequency converter (2) 39 Local oscillator (2) 40 Balanced modulator (2) 41 Spread signal Generator (2)
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.6,DB名) H04J 13/00 H04B 3/10 H04L 29/08──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. 6 , DB name) H04J 13/00 H04B 3/10 H04L 29/08
Claims (7)
して復調する受信系と、 送信データを変調し送信用の可変帯域瀘波器を介して送
信する送信系とからなるデータ伝送装置を用いた相互の
データ伝送方法において、 データ伝送の初期段階に広帯域信号を伝送し前記広帯域
信号の受信により伝送路の周波数振幅特性情報を測定し
て相互に伝送し、 前記周波数振幅特性情報が伝送路の周波数振幅特性の一
部落ち込みをしめしている場合、データ伝送速度を低減
し、周波数振幅特性の落ち込んでいない周波数帯域にお
いてデータ伝送を行う ことを特徴とするデータ伝送方
法。A received signal is passed through a variable band pass filter for reception.
And a demodulation system, which modulates the transmission data and transmits it through a variable band pass filter for transmission.
Using a data transmission device consisting of
In the data transmission method, a broadband signal is transmitted in an initial stage of data transmission, and the broadband signal is transmitted.
Measures the frequency and amplitude characteristic information of the transmission line by receiving the signal.
And the frequency amplitude characteristic information is one of the frequency amplitude characteristics of the transmission path.
Reduces data transmission speed when part drop occurs
In the frequency band where the frequency amplitude characteristics do not fall.
Data transmission method characterized in that data transmission is performed are.
数振幅特性の一部落ち込みをしめしている場合、前記送
信用の可変帯域瀘波器において、この落ち込んでいる一
部の帯域の通過を阻止することを特徴とする請求項1記
載のデータ伝送方法。 2. The method according to claim 1, wherein the frequency amplitude characteristic information is
If some of the amplitude characteristics show a drop,
In the credit variable bandpass filter, this depressed one
2. The device according to claim 1, wherein the band of the section is blocked.
Data transmission method described above.
を行うことを特徴とする請求項1又は2記載のデータ伝
送方法。 3. Data transmission by spread spectrum modulation
3. The data transmission according to claim 1, wherein the data transmission is performed.
How to send.
して復調する受信系と送信データを変調し送信用の可変
帯域瀘波器を介して送信する送信系とを含む装置間でデ
ータ伝送を行うデータ伝送装置において、 初期同期確立段階にデータ伝送装置の予め定められた周
波数帯域全体を使用して初期同期信号を相互に送信し、
初期同期信号の受信信号から周波数振幅特性を検出し、
検出された周波数振幅特性情報を相手に返し、前記周波
数振幅特性情報が伝送路の周波数振幅特性の一部落ち込
みを示している場合、データ伝送速度を低減し周波数振
幅特性の落ち込んでいない周波数帯域においてデータ伝
送を行うことを特徴とする データ伝送装置。4. A received signal is passed through a variable band pass filter for reception.
Receive and demodulate and modulate the transmission data and variable for transmission
A transmission system for transmitting via a bandpass filter.
In a data transmission apparatus that performs data transmission, a predetermined cycle of the data transmission apparatus is set in an initial synchronization establishment stage.
Transmit initial synchronization signals to each other using the entire wavenumber band,
Detect frequency amplitude characteristics from the received signal of the initial synchronization signal,
The detected frequency amplitude characteristic information is returned to the other party, and the frequency
Number amplitude characteristic information partially drops in frequency amplitude characteristics of transmission line
Data transmission rate, reduce the frequency transmission
Data transmission in frequency bands where the width characteristics do not fall
A data transmission device for transmitting data.
を行うことを特徴とする請求項4記載のデータ伝送装
置。5. Data transmission by spread spectrum modulation.
5. The data transmission device according to claim 4, wherein the data transmission is performed.
して逆拡散復調器で復調する受信系と、送信データを拡
散変調器で変調し送信用の可変帯域瀘波器を介して送信
する送信系と含むデータ伝送装置において、 前記受信信号の周波数振幅特性を検出するスペクトラム
分析部と、前記スペクトラム分析部から得られた周波数
振幅特性が一部帯域の落ち込みを示しているとき受信用
の可変帯域瀘波器の通過特性を落ち込んでいる一部帯域
を阻止するように制御するとともに、前記周波数振幅特
性の情報を前記送信系から送信される送信信号に重畳
し、且つ前記受信系で受信される受信信号に含まれる他
から送られてくる伝送路の周波数振幅特性が一部帯域の
落ち込みを示しているとき送信用の可変帯域瀘波器の通
過特性を落ち込んでいる一部帯域を阻止するように制御
する判定制御部とを有することを特徴とするデータ伝送
装置。 6. A received signal is passed through a variable band pass filter for reception.
The receiving system demodulates with the despread demodulator and the transmitted data is expanded.
Modulated by a spread modulator and transmitted through a variable bandpass filter for transmission
And a data transmission apparatus including a transmission system for detecting a frequency amplitude characteristic of the received signal.
An analysis unit, and a frequency obtained from the spectrum analysis unit.
For reception when the amplitude characteristic shows a drop in some bands
Of the variable bandpass filter
Frequency amplitude characteristics.
Information is superimposed on the transmission signal transmitted from the transmission system.
And included in the reception signal received by the reception system
The frequency amplitude characteristics of the transmission line sent from
When a drop is indicated, the transmission of the variable bandpass filter for transmission is performed.
Controls to block some bands that have degraded over-characteristics
Data transmission characterized by having a judgment control unit for performing
apparatus.
して逆拡散復調器で復調する受信系と、送信データを拡
散変調器で変調し送信用の可変帯域瀘波器を介して送信
する送信系と含むデータ伝送装置において、 前記受信信号の周波数振幅特性を検出するスペクトラム
分析部と、 前記スペクトラム分析部から得られた周波数振幅特性が
一部帯域の落ち込みを示しているとき、この周波数振幅
特性の情報を前記送信系から送信される送信信号に重畳
して送信し、前記受信系で受信される受信信号に含まれ
る他から送られてくる伝送路の周波数振幅特性の情報が
一部帯域の落ち込みを示しているとき前記送信系のデー
タ伝送速度を低減するように制御する判定制御部とを有
することを特徴とするデータ伝送装置。 7. A received signal is passed through a variable band pass filter for reception.
The receiving system demodulates with the despread demodulator and the transmitted data is expanded.
Modulated by a spread modulator and transmitted through a variable bandpass filter for transmission
And a data transmission apparatus including a transmission system for detecting a frequency amplitude characteristic of the received signal.
Analysis section, and the frequency amplitude characteristic obtained from the spectrum analysis section is
When showing a drop in some bands, this frequency amplitude
Characteristic information is superimposed on the transmission signal transmitted from the transmission system
Transmitted and included in the received signal received by the receiving system.
Information on the frequency and amplitude characteristics of the transmission path sent from other
When a drop in a part of the bandwidth is indicated,
And a decision control unit that controls to reduce the data transmission rate.
A data transmission device, comprising:
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP467696A JP2812278B2 (en) | 1996-01-16 | 1996-01-16 | Data transmission method and data transmission device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP467696A JP2812278B2 (en) | 1996-01-16 | 1996-01-16 | Data transmission method and data transmission device |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH09200079A JPH09200079A (en) | 1997-07-31 |
JP2812278B2 true JP2812278B2 (en) | 1998-10-22 |
Family
ID=11590508
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP467696A Expired - Fee Related JP2812278B2 (en) | 1996-01-16 | 1996-01-16 | Data transmission method and data transmission device |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP2812278B2 (en) |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS60197040A (en) * | 1984-03-21 | 1985-10-05 | Hitachi Ltd | Spectrum diffusion communicating device |
JPS62231527A (en) * | 1986-03-31 | 1987-10-12 | Nec Corp | Data transmission and reception equipment |
JPH01194613A (en) * | 1988-01-29 | 1989-08-04 | Hitachi Ltd | Automating equalizer initializing system |
JPH042226A (en) * | 1990-04-19 | 1992-01-07 | Nec Corp | Automatic equalizing system in communication system |
JPH04284730A (en) * | 1991-03-13 | 1992-10-09 | Nec Corp | Equalizer setting system for data transmitter-receiver |
JPH05252135A (en) * | 1992-03-03 | 1993-09-28 | Fujitsu Ltd | Spread spectrum communication system |
-
1996
- 1996-01-16 JP JP467696A patent/JP2812278B2/en not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
JPH09200079A (en) | 1997-07-31 |
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