JPH02121423A - Band narrowing system for spread spectrum radio communication - Google Patents
Band narrowing system for spread spectrum radio communicationInfo
- Publication number
- JPH02121423A JPH02121423A JP63272978A JP27297888A JPH02121423A JP H02121423 A JPH02121423 A JP H02121423A JP 63272978 A JP63272978 A JP 63272978A JP 27297888 A JP27297888 A JP 27297888A JP H02121423 A JPH02121423 A JP H02121423A
- Authority
- JP
- Japan
- Prior art keywords
- spread spectrum
- information
- modulation
- multiple access
- spread
- 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.)
- Pending
Links
- 238000001228 spectrum Methods 0.000 title claims abstract description 20
- 238000004891 communication Methods 0.000 title claims abstract description 15
- 230000005540 biological transmission Effects 0.000 claims abstract description 16
- 238000005516 engineering process Methods 0.000 claims abstract description 7
- 238000000034 method Methods 0.000 claims description 10
- 238000006243 chemical reaction Methods 0.000 abstract description 4
- 238000010586 diagram Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 3
- 230000001360 synchronised effect Effects 0.000 description 2
- 235000008694 Humulus lupulus Nutrition 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
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- Transmission Systems Not Characterized By The Medium Used For Transmission (AREA)
- Reduction Or Emphasis Of Bandwidth Of Signals (AREA)
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を用いた無線通信
に係り、特に周波数帯域幅の狭帯域化に好適な方法とこ
れを実現するための装置に関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to wireless communication using a spread spectrum communication method, and in particular to a method suitable for narrowing the frequency bandwidth and an apparatus for realizing this method. Regarding.
従来のスペクトラム拡散通信（周波数ポツピング方式）
については、スプレッド スペクトラムシステムズ（１
９８４年）第２８頁から第４２頁（ＳＰＲＥＡＤ Ｓ
ＰＥＣＴＲＵＭ ＳＹＳＴＥＭＳ （１９８４）ＰＰ
２８−４２３において論じられている。Conventional spread spectrum communication (frequency popping method)
For more information, please refer to Spread Spectrum Systems (1
984) pages 28 to 42 (SPREAD S
PECTRUM SYSTEMS (1984)PP
28-423.
前記従来技術は、スペクトラム拡散通信の広帯域通信に
よって得られる拡散復調時の処理利得の確保に主眼がお
かれており、一連の情報列を伝送するために必要な占有
周波数帯域幅の狭帯域化、またそれを補うための多元接
続については配慮がなされておらず、現在日本国内の電
波法との関連で、スペクトラム拡散通信の実用化のネッ
クになっている占有周波数帯域幅の拡大の問題は解決さ
れていない。The above-mentioned conventional technology mainly focuses on securing processing gain during spread demodulation obtained by wideband communication of spread spectrum communication, and narrows the occupied frequency bandwidth necessary for transmitting a series of information sequences. Furthermore, no consideration was given to multiple access to compensate for this, and the problem of expanding the occupied frequency bandwidth, which is currently a bottleneck to the practical application of spread spectrum communications in relation to Japan's Radio Law, has been resolved. It has not been.
本発明の目的は、多元接続の技術を応用して、スペクト
ラム拡散通信の中の周波数ポツピング方式を用いた時の
占有周波数帯域幅の狭帯域化をはかり、現行の国内電波
法の制約下でスペクトラム拡散通信の実用化への道を開
くことにある。The purpose of the present invention is to apply multiple access technology to narrow the occupied frequency bandwidth when using the frequency popping method in spread spectrum communication, and to narrow the occupied frequency bandwidth under the constraints of the current domestic radio law. The aim is to pave the way for the practical application of diffuse communication.
上記目的は、一連の伝送情報列を複数の回線に分割し、
多元接続の技術を用いてスペクトラム拡散変調をかける
ことにより、達成される。The above purpose is to divide a series of transmission information strings into multiple lines,
This is achieved by applying spread spectrum modulation using multiple access techniques.
伝送する一連のディジタル情報列を直／並列変換するこ
とにより、複数の情報列に分割する。この分割された情
報列に各々異なる拡散符号によって、スペクトラム拡散
変調をかける。この時の変調後の帯域帳は、もとの情報
列を分割しないで同じ処理利得を得るように拡散変調を
行なった場合に比べ、情報の伝送速度が遅い分だけ狭く
てよい。A series of digital information strings to be transmitted is divided into a plurality of information strings by performing serial/parallel conversion. Spread spectrum modulation is applied to each of the divided information strings using different spreading codes. The band book after modulation at this time may be narrower because the information transmission speed is slower than when spread modulation is performed to obtain the same processing gain without dividing the original information string.
もとの情報を完全に伝送するためには分割された各情報
列を全て多重化して受信側に伝送する必要があるが、こ
こで多元接続による多重を行なうことにより、分割され
た各情報列をそのまま拡散変調して伝送する場合に比べ
、狭帯域化が可能になる。In order to completely transmit the original information, it is necessary to multiplex all of the divided information strings and transmit them to the receiving side, but by performing multiplexing using multiple access, each divided information string Compared to the case where the signal is spread-modulated and transmitted as is, it is possible to narrow the band.
以下５本発明の一実施例を図面を用いて説明する。 An embodiment of the present invention will be described below with reference to the drawings.
第１図は本発明を適用した場合の伝送系の概咄を示す図
である。第１図に於いて入力するデータは例えば１５ｋ
ｂｐｓの情報列である。FIG. 1 is a diagram showing an outline of a transmission system when the present invention is applied. For example, the input data in Figure 1 is 15k.
This is an information string of bps.
送信機１の直／並列変換部５で、５ｋｂｐｓの伝送速度
を持つ３つの情報列に分配される。これに変調部３で２
７ｄＢの拡散処理利得が得られるよう周波数ホッピング
方式で拡散変調をかけると占有周波数帯域幅は２．５Ｍ
Ｈｚになる。これを伝送路上にのせて送信するが、ここ
で多元接続の技術を使い分割した各情報列を同一の周波
数帯域に重畳するので伝送路上の占有周波数帯域幅２゜
５ＭＨｚでよい。The serial/parallel converter 5 of the transmitter 1 distributes the information into three information streams having a transmission rate of 5 kbps. To this, the modulation section 3
If spreading modulation is applied using the frequency hopping method to obtain a spreading processing gain of 7 dB, the occupied frequency bandwidth will be 2.5M.
It becomes Hz. This is transmitted on a transmission path, and since each divided information string is superimposed on the same frequency band using multiple access technology, the occupied frequency bandwidth on the transmission path may be 2.5 MHz.
なお従来のスペクトラム拡散変調（周波数ホッピング変
調）を用いた無線通信系にいおいて、例えば前述の伝送
速度の情報に２７ ｄ Ｂの拡散処理利得を得られるよ
うに周波数ホッピング方式を用いた拡散変調をかけると
、伝送路上の占有周波数数帯域幅は７．５ＭＨｚになる
。In addition, in a wireless communication system using conventional spread spectrum modulation (frequency hopping modulation), spread modulation using a frequency hopping method is used to obtain a spreading processing gain of 27 dB for the above-mentioned transmission rate information, for example. When multiplied by , the occupied frequency bandwidth on the transmission path becomes 7.5 MHz.
受信機２に於いて、受信波は３チャンネル分用意されて
いる復調部４に送られる。復調部４では、各チャンネル
毎に固有の拡散符号を用いて、周波数シンセサイザの出
力周波数を可変し、周波数ホッピングされた受信信号を
復調する。復調された情報は並／直列変換部６により元
の１５ｋｂｐｓの情報に復元され出力される。In the receiver 2, the received waves are sent to a demodulator 4 prepared for three channels. The demodulator 4 varies the output frequency of the frequency synthesizer using a unique spreading code for each channel, and demodulates the frequency-hopped received signal. The demodulated information is restored to the original 15 kbps information by the parallel/serial converter 6 and output.
第２図は第１図で示した送信機１で、直／並列変換部５
．変調部３．高周波部７ＣＰＵ８から構成されている。FIG. 2 shows the transmitter 1 shown in FIG. 1, with the serial/parallel converter 5
．． Modulation section 3. It consists of a high frequency section 7 CPU8.
直／並列変換部５は、入力されたシリアルデータを３ｂ
ｉｔのパラレルデータに変換する。これによって１５ｋ
ｂｐｓで入力されてきた情報列は３本の５ｋｂｐｓ （
１５ｋｂｐｓ÷３）の情報列となり変調部３に送られる
。変調部３は、変調器１３．アップコンバータ１２２周
波数シンセサイザ１１．拡散符号発生器１０を各々３チ
ャネル分並列に持っており、ここでは分割された情報列
に変調器１３でディジタル変調をかけると同時にｃｐｕ
ｓからのコントロール信号によってタイミング発生器９
で各チャンネル毎タイミングパルスを発生する。各チャ
ンネルの拡散符号直交した拡散符号を発生する。周波数
シンセサイザ１１はその拡散符号にて出力周波数を高速
でホッピングさせ、変調のかかった情報を７ツプコンハ
ー１・すると同時に周波数ホッピング拡散を行なう。周
波数ホッピング拡散後の占有周波数帯域幅は処理利得を
２７ｃｌＢとすると２．５Ｍｌ−１ｚになる。このよう
に周波数ホッピング拡散でみかけ七２．５ＭＩ（ｚの占
有周波数帯域幅をもつ信号となり、その信号は高周波部
７に送られる。ここではまず最初に３本の２．５ＭＨｚ
の情報列は混合器１４によって占有周波数帯域幅２．５
Ｍ Ｈｚの１つの伝送帯域の中に混合させる。周波数
ホッピングに用いられた各情報の各拡散符号は各チャン
ネル毎に直交しているため、占有周波数帯域幅を広げる
ことなく多元接続が可能である。こうして多重化された
送信信号は、所要の送信電力を得るための高周波電力増
幅器１５．不要な帯域のノイズを除去する空中線フィル
タ１６．信号を空中に電磁波として放出する為の空中線
１７を経て、電波どして放出される。この高周波部７に
用いられる高周波電力増幅器１５．空中線フィルタ１６
．空中線１７は、スペクトラム拡散による広帯域に適応
できるものであれば通常の高周波回路用のもので良い。The serial/parallel converter 5 converts the input serial data into 3b
Convert it to parallel data. This will result in 15k
The information string input at bps is three 5kbps (
This becomes an information string of 15 kbps ÷ 3) and is sent to the modulator 3. The modulator 3 includes a modulator 13. Upconverter 122 Frequency Synthesizer 11. Each spread code generator 10 has 3 channels in parallel, and here the divided information string is digitally modulated by the modulator 13 and at the same time the CPU
The timing generator 9 is controlled by the control signal from s.
generates a timing pulse for each channel. A spreading code orthogonal to the spreading code of each channel is generated. The frequency synthesizer 11 hops the output frequency at high speed using its spreading code, and simultaneously performs frequency hopping spreading on the modulated information. The occupied frequency bandwidth after frequency hopping spreading is 2.5 Ml-1z when the processing gain is 27 clB. In this way, frequency hopping spreading results in a signal with an apparent occupied frequency bandwidth of 2.5 MI (z), and that signal is sent to the high frequency section 7. Here, first, three 2.5 MHz
The information string is processed by the mixer 14 into the occupied frequency bandwidth 2.5
Mix into one transmission band of MHz. Since the spreading codes of each piece of information used for frequency hopping are orthogonal for each channel, multiple access is possible without expanding the occupied frequency bandwidth. The multiplexed transmission signal is sent to a high frequency power amplifier 15 to obtain the required transmission power. Antenna filter 16 that removes noise in unnecessary bands. The signal is emitted as a radio wave through an antenna 17 for emitting the signal into the air as an electromagnetic wave. High frequency power amplifier 15 used in this high frequency section 7. antenna filter 16
．． The antenna 17 may be one for ordinary high frequency circuits as long as it can be applied to a wide band by spread spectrum.
ＣＰＵ８は操作パネルのスイッチ等の設定をもとにタイ
ミング発生器９等をコントロールするものである。The CPU 8 controls the timing generator 9 and the like based on the settings of switches and the like on the operation panel.
第３図は受信機２の構成図である。この装置は高周波部
７′、復調部４．並／直列変換部６．ＣＰＵ８ ’から
構成されている。FIG. 3 is a block diagram of the receiver 2. This device includes a high frequency section 7', a demodulation section 4. Parallel/serial converter 6. It consists of a CPU 8'.
空中線１７′によりキャッチされた受信波は受信帯域フ
ィルタ１８で帯域制限を受は不要な帯域のノイズを゛カ
ットし、低雑音増幅器１９で増幅される。ここで用いら
れる各構成品も送信機１の高周波部７と同様にスペクト
ラム拡散による広帯域に適用できるものであれば通常の
高周波回路用のもので良い。受信波は、高周波部７′と
復調部４の間で３つに分配されるがこれに対応して復調
部４の同期検出器２０．ダウンコンバータ２１１周波数
シンセサイザ１１′、拡散符号発生器１０′は各チャン
ネル分並列に持っている。分配された各受信波は同期検
出器２０によって周波数ホッピングの同期を検出しダウ
ンコンバータへ送られる。The received wave caught by the antenna 17' is band-limited by a reception band filter 18 to cut unnecessary band noise, and is amplified by a low-noise amplifier 19. Each component used here may be one for ordinary high frequency circuits as long as it can be applied to a wide band by spread spectrum, similar to the high frequency section 7 of the transmitter 1. The received wave is divided into three parts between the high frequency section 7' and the demodulation section 4, and the synchronous detector 20. A down converter 211, frequency synthesizer 11', and spreading code generator 10' are provided in parallel for each channel. Each distributed received wave detects frequency hopping synchronization by a synchronization detector 20 and is sent to a down converter.
タイミング発生器９′はＣＰＵ８ ’からのコントロー
ル信号に基づき送信機上の変調部３と同様にタイミング
パルスを発生する。拡散符号発生器１０′はタイミング
パルスを受けると同時に送信機１の変調部３と同様に拡
散符号を発生し周波数シンセサイザ１１′をその拡散符
号にて動作させる。The timing generator 9' generates timing pulses in the same way as the modulation section 3 on the transmitter based on the control signal from the CPU 8'. Upon receiving the timing pulse, the spreading code generator 10' generates a spreading code in the same way as the modulating section 3 of the transmitter 1, and operates the frequency synthesizer 11' using the spreading code.
この時各チャンネルの逆拡散のキーとなる拡散符号は各
チャンネル毎に直交しているため、この時点まで３チャ
ンネル分の情報を含んでいた受信波から必要とする受信
波のみダウンコンバートすることができる。こうしてダ
ウンコンバートされＩＦバンドに落された受信波は復調
器２２によってディジタル復調され、３本の情報列とな
る。この３本情報列は並／直列変換部６に送られて、こ
こで元のＬ５ｋｂｐｓの情報に復元され出力される。At this time, since the spreading codes that are the keys for despreading each channel are orthogonal for each channel, it is possible to down-convert only the necessary received waves from the received waves that have included information for three channels up to this point. can. The received wave thus down-converted and dropped into the IF band is digitally demodulated by the demodulator 22 and becomes three information streams. These three information streams are sent to the parallel/serial converter 6, where they are restored to the original L5 kbps information and output.
本実施例によれば、従来の方式で復調時にスペクトラム
拡散処理利得２７ｄＢ得ようとした場合、占有周波数帯
域幅として７．５ＭＨｚが必要であったものが、２．５
ＭＨｚに狭めることができる等の効果がある。According to this embodiment, when attempting to obtain a spread spectrum processing gain of 27 dB during demodulation using the conventional method, the occupied frequency bandwidth of 7.5 MHz is reduced to 2.5 MHz.
There are effects such as being able to narrow the frequency to MHz.
なお、実施例では情報列を３分割したため、占有周波数
帯域幅を１／３にすることができたが、理論的には情報
の分割数を増やせばより狭帯域化が可能になる。つまり
、本発明によれば元の情報列の分割数をｎとすれば占有
周波数帯域幅は本発明を用いない場合の１ ／ ｎにす
ることができる。Note that in the embodiment, the information string was divided into three, so the occupied frequency bandwidth could be reduced to one-third, but theoretically, if the number of information divisions is increased, the band can be made narrower. That is, according to the present invention, if the number of divisions of the original information string is n, the occupied frequency bandwidth can be reduced to 1/n of that in the case where the present invention is not used.
〔発明の効果〕
本発明によれば、スペクトラム拡散を用いた無線通信に
おける占有周波数帯域幅を狭帯域化できる。[Effects of the Invention] According to the present invention, the occupied frequency bandwidth in wireless communication using spread spectrum can be narrowed.
この結果、無線回線の狭帯域化による電波資源の有効活
用が図れ、また現行電波法の制約下でもスペクトラム拡
散通信の実用化が図れる。更に、この狭帯域化により、
より低い周波数帯でスペクトラム拡散通信を使用するこ
ともできる。As a result, it is possible to effectively utilize radio wave resources by narrowing the band of the wireless line, and it is also possible to put spread spectrum communication into practical use even under the restrictions of the current radio law. Furthermore, due to this narrow band,
Spread spectrum communications can also be used in lower frequency bands.
第１図は本発明を適用した場合の伝送系の概念図、第２
図は本実施例の送信機の構成図、第３図は同受信機の構
成図である。
１・・・送信機、２・・・受信機、３・・・変調部、４
・・・復調部、５・・直／並列変換部、６・・・並／直
列変換部、７．７’−・・高周波部、８．８ ’＝−Ｃ
ＰＵ、９．９・タイミング発生器、１０．１０’・・・
拡散符号発生器、１１．１１’・・・周波数シンセサイ
ザ、１２・・・アップコンバータ、１３・・・変調器、
１４・・・混合器、１５・・・高周波電力増幅器、１６
・・・空中線フィルタ、１７．１７’・・・空中線、１
８・・・受信帯域フィルタ、１９・・・低雑音増幅器、
２０・・・同期検出器、２１ダウンコンバータ、２２・
・・復調器。
１−ｍ−ΩＬイ乞斗）（
２−ｍ−受イ訂シ（
３−ｍ−更訓音μ
４−−− ＫＬ耐邦
ターーー
亘／Ｌｆ−戊槙邦
乙−−一
並、／直夕１ｊりと１奥＃ρ
″ｊ！！：、３図Figure 1 is a conceptual diagram of the transmission system when the present invention is applied, Figure 2
The figure is a block diagram of the transmitter of this embodiment, and FIG. 3 is a block diagram of the receiver. 1... Transmitter, 2... Receiver, 3... Modulation section, 4
...Demodulation section, 5..Serial/parallel conversion section, 6..Parallel/serial conversion section, 7.7'-..High frequency section, 8.8'=-C
PU, 9.9・Timing generator, 10.10'...
Spreading code generator, 11.11'... Frequency synthesizer, 12... Up converter, 13... Modulator,
14...Mixer, 15...High frequency power amplifier, 16
...Antenna filter, 17.17'...Antenna, 1
8... Reception band filter, 19... Low noise amplifier,
20... synchronous detector, 21 down converter, 22...
...Demodulator. 1-m-ΩL i begged) (2-m-revision (3-m-furry sound μ) 4--- KL Taibokuta--Wataru/Lf-Bomakikunitsu--Ichinami, /Nao Evening 1j Rito 1 Oku #ρ ″j!!:, 3 figures
Claims (1)
より絶対的に必要な占有周波数帯域幅より広い占有周波
数帯域幅を使用する拡散変調方式において伝送情報を複
数に分割し、各々異なる前記拡散符号によって前記搬送
波を周波数ホッピングさせたうえで、多元接続技術を用
い同一無線周波数帯で伝送することを特徴とするスペク
トラム拡散無線通信の狭帯域化方式。1. In a spreading modulation method that uses an occupied frequency bandwidth wider than the absolutely necessary occupied frequency bandwidth by hopping the carrier wave with a spreading code, transmission information is divided into multiple parts, and the carrier wave is divided into multiple parts, each using a different spreading code. A narrowband spread spectrum wireless communication method that uses frequency hopping and then transmits in the same radio frequency band using multiple access technology.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63272978A JPH02121423A (en) | 1988-10-31 | 1988-10-31 | Band narrowing system for spread spectrum radio communication |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63272978A JPH02121423A (en) | 1988-10-31 | 1988-10-31 | Band narrowing system for spread spectrum radio communication |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH02121423A true JPH02121423A (en) | 1990-05-09 |
Family
ID=17521444
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63272978A Pending JPH02121423A (en) | 1988-10-31 | 1988-10-31 | Band narrowing system for spread spectrum radio communication |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02121423A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04324729A (en) * | 1991-04-24 | 1992-11-13 | Victor Co Of Japan Ltd | Modulation and demodulation method for digital radio communication and its equipment |
| JPH04360494A (en) * | 1991-06-07 | 1992-12-14 | Canon Inc | Telephone exchange |
| JPH05347599A (en) * | 1992-06-15 | 1993-12-27 | Matsushita Electric Ind Co Ltd | High speed data transmitting device |
| JPH10178369A (en) * | 1996-12-18 | 1998-06-30 | Nec Corp | Receiver |
| JP2003191075A (en) * | 2001-12-25 | 2003-07-08 | Daihen Corp | Consumable electrode type arc welding equipment |
| JP2003236663A (en) * | 2002-02-19 | 2003-08-26 | Daihen Corp | Nonconsumable electrode type arc welding equipment |
-
1988
- 1988-10-31 JP JP63272978A patent/JPH02121423A/en active Pending
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04324729A (en) * | 1991-04-24 | 1992-11-13 | Victor Co Of Japan Ltd | Modulation and demodulation method for digital radio communication and its equipment |
| JPH04360494A (en) * | 1991-06-07 | 1992-12-14 | Canon Inc | Telephone exchange |
| JPH05347599A (en) * | 1992-06-15 | 1993-12-27 | Matsushita Electric Ind Co Ltd | High speed data transmitting device |
| JPH10178369A (en) * | 1996-12-18 | 1998-06-30 | Nec Corp | Receiver |
| JP2003191075A (en) * | 2001-12-25 | 2003-07-08 | Daihen Corp | Consumable electrode type arc welding equipment |
| JP4739621B2 (en) * | 2001-12-25 | 2011-08-03 | 株式会社ダイヘン | Consumable electrode arc welding equipment |
| JP2003236663A (en) * | 2002-02-19 | 2003-08-26 | Daihen Corp | Nonconsumable electrode type arc welding equipment |
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