JPH01213041A - Digital microwave communication equipment - Google Patents
Digital microwave communication equipmentInfo
- Publication number
- JPH01213041A JPH01213041A JP3744388A JP3744388A JPH01213041A JP H01213041 A JPH01213041 A JP H01213041A JP 3744388 A JP3744388 A JP 3744388A JP 3744388 A JP3744388 A JP 3744388A JP H01213041 A JPH01213041 A JP H01213041A
- Authority
- JP
- Japan
- Prior art keywords
- band
- filter
- digital microwave
- microwave communication
- modulation spectrum
- 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 claims abstract description 15
- 230000005540 biological transmission Effects 0.000 description 6
- 238000010586 diagram Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 2
- 238000003379 elimination reaction Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
Landscapes
- Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
Abstract
Description
【発明の詳細な説明】
［産業上の利用分野］
本発明は、デジタルマイクロ波通信装置に間し、特に、
マイクロ波通信方式における周波数利用効率を低下させ
ないで隣接チャンネル間干渉を小さくしたデジタルマイ
クロ波通信装置に関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a digital microwave communication device, and in particular,
The present invention relates to a digital microwave communication device that reduces interference between adjacent channels without reducing frequency utilization efficiency in a microwave communication system.
［従来の技術］
一般に、ｎ値ＰＳＫ、ＱＡＭ変調方式を用いたデジタル
マイクロ波通信では、隣接チャンネル間干渉が生しる。[Prior Art] Generally, in digital microwave communication using n-value PSK and QAM modulation methods, interference between adjacent channels occurs.
第３図は、従来のデジタルマイクロ波通信装置における
変調スペクトラムを示す図である。FIG. 3 is a diagram showing a modulation spectrum in a conventional digital microwave communication device.
同図に示すように隣接チャンネル間で、変調スペクトラ
ムの帯域端が重複するため、干渉が生じるのである。As shown in the figure, interference occurs because the band edges of the modulation spectra overlap between adjacent channels.
従って、従来のデジタルマイクロ波通信装置では、隣接
チャンネル間干渉を考えて伝送容量が決定されていた。Therefore, in conventional digital microwave communication devices, transmission capacity has been determined by taking into account interference between adjacent channels.
［解決すべき問題点］
上述した従来のデジタルマイクロ波通信装置は、伝送容
量を大きくすると変調スペクトラムが広がるため、シス
テム上必要とされる隣接チャンネル間干渉に対する許容
信号対雑音比を確保することが難しいという問題点があ
った。[Problems to be solved] In the conventional digital microwave communication device described above, as the transmission capacity increases, the modulation spectrum widens, so it is difficult to secure an acceptable signal-to-noise ratio against interference between adjacent channels, which is required for the system. The problem was that it was difficult.
また、システム上必要とされる許容信号対雑音比は、多
値になればなるほど大きくなるため、多値化によって伝
送容量を大きくしようとする場合であっても、必要十分
な許容信号対雑音比を確保すること困難となるという問
題点があった。In addition, the allowable signal-to-noise ratio required for a system increases as the number of values increases. There was a problem in that it was difficult to secure.
本発明は、上記問題点にかんがみてなされたもので、周
波数利用効率を低下させないで隣接チャンネル間干渉を
小さくするデジタルマイクロ波通信装置の提供を目的と
する。The present invention has been made in view of the above problems, and aims to provide a digital microwave communication device that reduces interference between adjacent channels without reducing frequency utilization efficiency.
［問題点の解決手段］
上記目的を達成するため、本発明のデジタルマイクロ波
通信装置は、送信側に変調スペクトラムの帯域端を削る
ろ波器を備えた構成としである。[Means for Solving Problems] In order to achieve the above object, the digital microwave communication device of the present invention is configured to include a filter on the transmitting side that cuts the band edge of the modulation spectrum.
すなわち、ｎ （直Ｐ Ｓ Ｋ、 ＱＡＭ変調方式を用
いたデジタルマイクロ波通信において、システムの伝送
特性に影響を与えない程度にその変調スペクトラムの帯
域端を削り、隣接チャンネル間干渉を小さくしている。In other words, in digital microwave communication using direct PSK, QAM modulation, the band edge of the modulation spectrum is shaved to the extent that it does not affect the transmission characteristics of the system, reducing interference between adjacent channels. .
［実施例コ 以下、図面にもとづいて本発明の詳細な説明する。[Example code] Hereinafter, the present invention will be explained in detail based on the drawings.
第１図は、本発明の一実施例に係るデジタルマイクロ波
通信装置の送信側主要部のフロック図である。FIG. 1 is a block diagram of the main parts on the transmitting side of a digital microwave communication device according to an embodiment of the present invention.
本発明は、伝送容量を大きくしていくと、システム上必
要とされる隣接チャンネル間干渉に対する許容信号対雑
音比を確保することが難しくなるため、伝送特性に影響
を与えない程度に変調器の変調スペクトラムの帯域端を
削り、規定の隣接チャンネル間干渉に対する許容信号対
雑音比を確保するものである。As the transmission capacity increases, it becomes difficult to secure an acceptable signal-to-noise ratio against interference between adjacent channels, which is required for the system. It cuts the band edges of the modulation spectrum to ensure an acceptable signal-to-noise ratio for specified adjacent channel interference.
第１図において、１は変調波信号ａを帯域制限するため
の帯域ろ波器である。また、２は帯域消去る波器であり
、帯域ろ波器１の出力端に結線され、この帯域ろ波器１
によって帯域制限された変調波信号の帯域端を削る。In FIG. 1, reference numeral 1 denotes a bandpass filter for band-limiting the modulated wave signal a. Further, reference numeral 2 denotes a band canceling filter, which is connected to the output end of the band filter 1.
The band edge of the modulated wave signal that has been band-limited by is removed.
そして、３は送信器であり、帯域消去る波器２を通った
変調波信号が、この送信器３から出力される。3 is a transmitter, and the modulated wave signal that has passed through the band canceling wave device 2 is outputted from the transmitter 3.
また、第２図は第１図における変調スペクトラムを示す
図であり、帯域端を削った後の変調スペクトラムである
。Moreover, FIG. 2 is a diagram showing the modulation spectrum in FIG. 1, and is the modulation spectrum after the band edges have been removed.
同図に示すように、本実施例の場合は、隣接チャンネル
間で変調スペクトラムの帯域端が重複することがなくな
るため、干渉が生じることもない。As shown in the figure, in this embodiment, the band edges of modulation spectra do not overlap between adjacent channels, so no interference occurs.
従って、伝送容量を大きくすることができ、周波数利用
効率も向上する。Therefore, the transmission capacity can be increased and the frequency usage efficiency can also be improved.
なお、本発明は上記実施例に限定されるものでなく、要
旨の範囲内における種々変形例を含むものである。例え
ば、上述の実施例では、帯域消去ろ波器を使用している
が、伝送特性に影響が無い程度に帯域端を削ることがで
きればよい。従って、帯域消去ろ波器以外のものでも良
い。It should be noted that the present invention is not limited to the above embodiments, but includes various modifications within the scope of the gist. For example, in the above-described embodiment, a band-elimination filter is used, but it is only necessary to reduce the band edge to the extent that the transmission characteristics are not affected. Therefore, something other than a band-stop filter may be used.
［発明の効果］
以上説明したように本発明は、隣接チャンネル間干渉を
減少させることにより、周波数利用効率を向上せしめる
ことが可能なデジタルマイクロ波通信装置を提供できる
という効果がある。[Effects of the Invention] As described above, the present invention has the effect of providing a digital microwave communication device that can improve frequency usage efficiency by reducing interference between adjacent channels.
第１図は本発明の一実施例に係るデジタルマイクロ波通
信装置のブロック図、第２図は第１図に示すデジタルマ
イクロ波通信装置における変調スペクトラムを示す図、
第３図は従来のデジタルマイクロ波通信装置における変
調スペクトラムを示す図である。
１：帯域ろ波器
２：帯域消去ろ波器
３：送信器FIG. 1 is a block diagram of a digital microwave communication device according to an embodiment of the present invention, and FIG. 2 is a diagram showing a modulation spectrum in the digital microwave communication device shown in FIG.
FIG. 3 is a diagram showing a modulation spectrum in a conventional digital microwave communication device. 1: Bandpass filter 2: Band-stop filter 3: Transmitter
Claims (1)
することを特徴とするデジタルマイクロ波通信装置。A digital microwave communication device characterized in that a transmitting side is equipped with a filter that cuts the band edge of a modulation spectrum.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3744388A JPH01213041A (en) | 1988-02-22 | 1988-02-22 | Digital microwave communication equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3744388A JPH01213041A (en) | 1988-02-22 | 1988-02-22 | Digital microwave communication equipment |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01213041A true JPH01213041A (en) | 1989-08-25 |
Family
ID=12497650
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3744388A Pending JPH01213041A (en) | 1988-02-22 | 1988-02-22 | Digital microwave communication equipment |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01213041A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6000505A (en) * | 1998-03-31 | 1999-12-14 | Allen; Thomas H. | Multiple level building with an elevator system operable as a means of emergency egress and evacuation during a fire incident |
-
1988
- 1988-02-22 JP JP3744388A patent/JPH01213041A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6000505A (en) * | 1998-03-31 | 1999-12-14 | Allen; Thomas H. | Multiple level building with an elevator system operable as a means of emergency egress and evacuation during a fire incident |
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