JPH0588014B2 - - Google Patents

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Publication number
JPH0588014B2
JPH0588014B2 JP1936580A JP1936580A JPH0588014B2 JP H0588014 B2 JPH0588014 B2 JP H0588014B2 JP 1936580 A JP1936580 A JP 1936580A JP 1936580 A JP1936580 A JP 1936580A JP H0588014 B2 JPH0588014 B2 JP H0588014B2
Authority
JP
Japan
Prior art keywords
frequency
receiving
local oscillator
transmission
transmitting
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 - Lifetime
Application number
JP1936580A
Other languages
Japanese (ja)
Other versions
JPS56116348A (en
Inventor
Shigeru Aono
Michiaki Myazono
Osamu Oonada
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.)
Fujitsu Ltd
Original Assignee
Fujitsu Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP1936580A priority Critical patent/JPS56116348A/en
Publication of JPS56116348A publication Critical patent/JPS56116348A/en
Publication of JPH0588014B2 publication Critical patent/JPH0588014B2/ja
Granted legal-status Critical Current

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Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04JMULTIPLEX COMMUNICATION
    • H04J1/00Frequency-division multiplex systems

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Transceivers (AREA)

Description

【発明の詳細な説明】 本発明はマイクロ波多重無線装置に関する。[Detailed description of the invention] The present invention relates to a microwave multiplex radio device.

一般にマイクロ波多重無線装置の送信周波数と
受信周波数は、複数のマイクロ多重無線装置で構
成されるマイクロ多重無線システムで予め決めら
れた周波数帯域内の1の周波数にそれぞれ固定さ
れており、従つて当該装置内の送信系および受信
系を構成する部品、例えばフイルタ素子等はその
1つの周波数にのみ適合すれば十分その機能を果
すことができる。ところが、近時、前記送信周波
数ならびに受信周波数を1つの周波数に固定する
のではなく、前記決められた周波数帯域内で可変
にしたいという要求が生じてきた。この場合、前
記決められた周波数帯域内で送・受信周波数を任
意に変更することは例えば960チヤネルにも及ぶ
多重通信を行なう場合においては最早、送・受信
周波数を単純に変更することは困難となる。とい
うのは、前述したフイルタ素子等の部品が、変更
が予定される各送・受信周波数の全てに適合し得
る機能を発揮しなければならなくなるからであ
る。勿論、各該送・受信周波数に適合する部品群
を、送信系ならびに受信系に予め具備させておけ
ば当該要求は簡単に満足される。然し、これは不
経済極りない、従つて本発明の目的は、前述の問
題を排除して送・受信周波数の変更が行なえる、
マイクロ波多重無線装置を提供することである。
Generally, the transmission frequency and reception frequency of a microwave multiplex radio device are each fixed at one frequency within a predetermined frequency band in a micro multiplex radio system composed of a plurality of micro multiplex radio devices. The components constituting the transmitting system and receiving system within the device, such as filter elements, can sufficiently perform their functions if they are compatible with only one frequency. However, recently, there has been a demand for making the transmission frequency and reception frequency variable within the determined frequency band, rather than fixing them to one frequency. In this case, it is no longer possible to simply change the transmitting and receiving frequencies arbitrarily within the determined frequency band, for example when performing multiplex communication with as many as 960 channels. Become. This is because components such as the filter elements described above must perform functions that can be adapted to all of the transmission and reception frequencies that are planned to be changed. Of course, this requirement can be easily met if the transmitting system and the receiving system are equipped in advance with a group of parts that are compatible with each of the transmitting and receiving frequencies. However, this is extremely uneconomical, so the object of the present invention is to eliminate the above-mentioned problems and to be able to change the transmitting and receiving frequencies.
An object of the present invention is to provide a microwave multiplex radio device.

上記目的に従い本発明は、送信系において送信
すべきベースバンド信号で変調された送信系中間
周波数を送信周波数の略数分の1とし、一方、受
信系においては受信周波数の略数分の1の第1受
信系中間周波数と、これを周波数変換した第2受
信系中間周波数とを存在せしめ、さらに前記送信
系および受信系局部発振器は共用とし、さらにま
た、送信系送信周波数および受信系受信周波数の
周波数差の2倍の周波数差をもつた第1および第
2の受信系局部発振器を備えることにより、前記
の周波数変換が、該第1または第2の受信系局部
発振器からの出力周波数のいずれか一方の周波数
混合によつて行なわれるようにしたことを特徴と
するものである。
In accordance with the above object, the present invention sets the transmitting system intermediate frequency modulated by the baseband signal to be transmitted in the transmitting system to approximately one fraction of the transmitting frequency, while in the receiving system, the transmitting system intermediate frequency is approximately one fraction of the receiving frequency. A first receiving system intermediate frequency and a second receiving system intermediate frequency obtained by converting the frequency of the first receiving system intermediate frequency are provided, the transmitting system and the receiving system local oscillator are shared, and furthermore, the transmitting system transmitting frequency and the receiving system receiving frequency are By providing the first and second receiving system local oscillators with a frequency difference twice the frequency difference, the frequency conversion can be performed on either the output frequency from the first or second receiving system local oscillator. This is characterized in that it is performed by one frequency mixing.

以下図面に従つて本発明を説明する。 The present invention will be explained below with reference to the drawings.

添付図は本発明に基づくマイクロ波無線通信方
式を実施する装置の一実施例を示すブロツク図で
ある。本図において、Binは送信すべきベースバ
ンド信号であり、変調器11において所定のの周
波数で変調され、送信系中間周波信号IFtを得る。
信号IFtは周波数変換器12において局部発振出
力信号μtと周波数混合される。こで信号IFt信号
μtおよび送信信号FTの周波数をそれぞれ
(IFt)、(μt)および(Ft)とすれば、例えば
(IFt)+(μt)=(Ft)の信号成分のみがフイ
ルタ13で抽出され、増幅器14にて所定レベル
まで増幅された後、送受共用器15を介してアン
テナ16より送信される。
The attached figure is a block diagram showing an embodiment of a device implementing a microwave wireless communication system according to the present invention. In this figure, Bin is a baseband signal to be transmitted, which is modulated by a modulator 11 at a predetermined frequency to obtain a transmission intermediate frequency signal IFt.
The signal IFt is frequency mixed with the local oscillation output signal μt in the frequency converter 12. Here, if the frequencies of the signal IFt signal μt and the transmission signal FT are (IFt), (μt), and (Ft), respectively, only the signal component of (IFt) + (μt) = (Ft) is extracted by the filter 13. After being amplified to a predetermined level by an amplifier 14, it is transmitted from an antenna 16 via a duplexer 15.

上述したブロツク11〜16の構成は従来と何
ら異なるところが無い。ただし、信号IFtの周波
数(IFt)の設定が従来と異なる。この周波数
(IFt)は、本発明においては従来のそれより遥か
に高く、例えばGHzオーダに選ぶ。
The configurations of the blocks 11 to 16 described above are no different from the conventional ones. However, the setting of the frequency (IFt) of the signal IFt is different from the conventional one. In the present invention, this frequency (IFt) is much higher than the conventional one, for example, on the order of GHz.

本発明の主題は、既述の如く、送信周波数
(Ft)を任意に変更することである。すなわち、
前記信号μtの周波数(μt)を前記決められた周
波数帯域内で変更することである。この変更に対
処する場合、フイルタ13の機能が問題となる。
言うまでもなくフイルタ13は周波数変換器12
からの出力のうち送信信号とならない不要波を除
去することにあるが、従来の様に100MHz前後の
IFtが重畳された信号FTを例えば数100MHzの範
囲で変更した後も、なおかつ単一のフイルタ13
に不要波の除去操作を行なわしめることは困難で
ある。ところが、本発明の様に高い周波数のIFt
が重畳された信号FTであれば、数100MHz程度の
範囲で該信号μtを変更しても、フイルタ13にと
つて不要波の除去操作は容易である。ただし、フ
イルタ13には予め前記決められた周波数帯域で
の通過特性を持たせておく。また、増幅器14も
同様の周波数特性を持たせておく。かくして、送
信系では送信系中間周波数(IFt)を一定周波数
とし、該局部発振出力信号μtの周波数(μt)だ
けを変更することにより所望の周波数変更が行な
えることになる。
As mentioned above, the subject matter of the present invention is to arbitrarily change the transmission frequency (Ft). That is,
The purpose is to change the frequency (μt) of the signal μt within the determined frequency band. When dealing with this change, the function of the filter 13 becomes a problem.
Needless to say, the filter 13 is the frequency converter 12.
The purpose is to remove unnecessary waves that do not become transmission signals from the output from the
Even after changing the signal FT on which IFt is superimposed, for example, in the range of several 100 MHz, still only a single filter 13
It is difficult to perform an operation to remove unnecessary waves. However, as in the present invention, high frequency IFt
If the signal FT is a superimposed signal, it is easy for the filter 13 to remove unnecessary waves even if the signal μt is changed within a range of several hundred MHz. However, the filter 13 is provided with a pass characteristic in the predetermined frequency band. Further, the amplifier 14 is also provided with similar frequency characteristics. Thus, in the transmission system, the desired frequency can be changed by setting the transmission system intermediate frequency (IFt) to a constant frequency and changing only the frequency (μt) of the local oscillation output signal μt.

一方、相手局(図示しないが、本図と同一の構
成を有する)からの信号は、受信信号Frとして
アンテナ16に入力され、送受共用器15および
受信分波器31を介して増幅器32により、所定
レベルまで増幅される。さらにフイルタ33にお
いて所望の受信信号Frのみが抽出され、第1周
波数変換器34に印加される、ここに受信分波器
31およびフイルタ33には予め前記規定周波数
帯域での通過特性を持たせておき、また増幅器3
2も同様の周波数特性を持たせておく。第1周波
数変換器34において受信信号Frは局部発信出
力信号μrと周波数混合され、ここに第1受信系中
間周波信号IFr1を得る。この信号IFr1の周波数
(IFr1)は前述の(IFt)に相当しGHzオーダの
高い周波数である。この第1受信系中間周波数信
号IFr1は、増幅器35ならびにフイルタ36を経
由することにより、所定レベルで且つ不要波を除
去した信号となる。ここに、増幅器35およびフ
イルタ36が前記決められた周波数帯域で所望の
特性を発揮することは、既に増幅器14,32お
よびフイルタ13,33に関して述べたのと同様
である。送・受信周波数は如何なる周波数に変更
されようとも、両者は常に一定の関係を保つてい
ることが必要であるから、前述した送信系局部発
振出力信号μtおよび受信系局部発振出力信号μr
は、単一の局部発振器22を共用して出力され、
分割器23によつて送信系または受信系に分配さ
れる。このように、単一の局部部発振器を共用す
ることは本発明の実施上重要なことである。
On the other hand, a signal from a partner station (not shown, but having the same configuration as in this figure) is input to the antenna 16 as a received signal Fr, and transmitted by the amplifier 32 via the duplexer 15 and the receiver duplexer 31. is amplified to a predetermined level. Further, in the filter 33, only the desired received signal Fr is extracted and applied to the first frequency converter 34. Next, amplifier 3
2 has similar frequency characteristics. In the first frequency converter 34, the received signal Fr is frequency-mixed with the local oscillation output signal μr, thereby obtaining the first receiving system intermediate frequency signal IFr1 . The frequency (IFr 1 ) of this signal IFr 1 corresponds to the above-mentioned (IFt) and is a high frequency on the order of GHz. This first receiving system intermediate frequency signal IFr 1 passes through an amplifier 35 and a filter 36 to become a signal at a predetermined level and from which unnecessary waves have been removed. Here, the fact that the amplifier 35 and the filter 36 exhibit desired characteristics in the determined frequency band is similar to what has already been stated regarding the amplifiers 14 and 32 and the filters 13 and 33. No matter how the transmitting and receiving frequencies are changed, it is necessary that they always maintain a constant relationship, so the above-mentioned transmitting system local oscillation output signal μt and receiving system local oscillation output signal μr
are output using a single local oscillator 22,
The signal is distributed by the divider 23 to the transmitting system or the receiving system. Thus, sharing a single local oscillator is important in implementing the present invention.

上述したとおり、送・受信周波数は常に一定の
関係を保つことが必要である。この一定の関係と
は、第1に(Ft)−(Fr)=Δを満足すること
である。周知の如く、Δなる差を持たせるのは、
同一局内での送・受信信号の廻り込みを防止する
ためである。また、第2には、同一局において
(Ft)で送信する場合には(Fr)で受信し、逆
に(Fr)と同じ周波数で送信する場合には
(Ft)と同じ周波数で受信し、且ついずれの形態
になるか任意的である。上述の関係を勘案する
と、受信系においてフイルタ36から出力される
第1受信系中間周波信号IFr1の周波数(IFr1
と、送信系中間周波信号IFtの周波数(IFt)と
の間には、(IFr1)=(IFt)+Δまたは
(IFr1)=(IFt)−Δなる関係が成立する。結
局、フイルタ36の出力には上記2式のいずれか
一方で表わされる信号が現われることになる。そ
こで、さらに、第2周波数変換器41を新設す
る。その出力は第2受信系中間周波信号IFr2であ
り、単一且つ低周波の中間周波信号である。とい
うのは、変換器41がスイツチ42を介し、第1
局部発振器43または第2局部発振器44と択一
的に協働するからである。もし、フイルタ36か
らの出力の周波数(IFr1)が(IFr1)=(IFt)
+Δであれば、(IFt)+(IFr2)+Δなる第

局部発振器43の出力が選択され、第2中間周波
信号の周波数は(IFr2)となる。逆に、もしフ
イルタ36からの出力の周波数(IFr1)が
(IFr1)=(IFt)−Δであれば、(IFt)+
(IFr2)−Δなる第2局部発振器44の出力が選
択され、同じく第2中間周波信号の周波数は
(IFr2)となる。即ち、(It)+(IFr2)+Δ

{(It)+(IFr2)−Δ}=2Δなる周波数
差を
持つた第1、第2の局部発振器を用いることによ
り受信周波数にかかわらず一定の第2中間周波信
号の周波数(IFr2)を得ることができる。第1
または第2の局部発振器のいずれを選択するかは
スイツチ42で操作され、スイツチ42は周波数
検出器あるいは等価的に周波数を検出できる検出
器21により制御される。すなわち、局部発振器
22が送信信号の周波数として、(Ft)−
(Fr)=Δなる周波数を、設定しているか、ある
いは(Fr)−(Ft)=Δなる周波数を設定して
いるから送信周波数と受信周波数とは一定の周波
数差を持つて一義的に決まつている。つまり、周
波数帯域内で送信周波数が高い周波数に属すれ
ば、受信周波数が送信周波数に比べ一定の周波数
差分低い周波数を持ち、送信周波数が低い周波数
に属すれば受信周波数が送信周波数に比べ一定の
周波数差分高い周波数を持つ。そのことから、送
信周波数を決めている局部発振器22の周波数を
検出することにより受信周波数が高い周波数に属
するか、低い周波数に属するかが一義的に決める
事が出来る。よつて、局部発振器22の出力を検
出器21で検出することにより、第1あるいは第
2の局部発振器43,44のどちらか一方の出力
を選択する。以後、単一且つ低周波の第2中間周
波信号IFr2は、増幅器45、フイルタ46および
復調器47を通してベースバンド信号Boutに変
換される。
As mentioned above, it is necessary to always maintain a constant relationship between the transmitting and receiving frequencies. This constant relationship firstly means that (Ft)-(Fr)=Δ is satisfied. As is well known, the reason for having a difference of Δ is
This is to prevent transmission and reception signals from going around within the same station. Secondly, when transmitting on (Ft) on the same station, it is received on (Fr), and conversely, when transmitting on the same frequency as (Fr), it is received on the same frequency as (Ft), Moreover, the form is arbitrary. Considering the above relationship, the frequency (IFr 1 ) of the first receiving system intermediate frequency signal IFr 1 output from the filter 36 in the receiving system
and the frequency (IFt) of the transmission intermediate frequency signal IFt, the following relationship holds true: (IFr 1 )=(IFt)+Δ or (IFr 1 )=(IFt)−Δ. As a result, a signal expressed by one of the above two equations will appear at the output of the filter 36. Therefore, a second frequency converter 41 is additionally installed. The output is the second receiving system intermediate frequency signal IFr2 , which is a single low frequency intermediate frequency signal. This is because the converter 41, via the switch 42,
This is because it selectively cooperates with the local oscillator 43 or the second local oscillator 44. If the frequency (IFr 1 ) of the output from the filter 36 is (IFr 1 ) = (IFt)
If +Δ, then (IFt) + (IFr 2 ) + Δ, the first
The output of the local oscillator 43 is selected, and the frequency of the second intermediate frequency signal becomes (IFr 2 ). Conversely, if the frequency (IFr 1 ) of the output from the filter 36 is (IFr 1 ) = (IFt) - Δ, then (IFt) +
The output of the second local oscillator 44 of (IFr 2 )−Δ is selected, and the frequency of the second intermediate frequency signal is also (IFr 2 ). That is, (It) + (IFr 2 ) + Δ

By using the first and second local oscillators with a frequency difference of {(It) + (IFr 2 ) - Δ} = 2Δ, the frequency of the second intermediate frequency signal (IFr 2 ) is constant regardless of the reception frequency. can be obtained. 1st
The switch 42 is used to select either the local oscillator or the second local oscillator, and the switch 42 is controlled by the frequency detector or equivalently the detector 21 capable of detecting the frequency. That is, the local oscillator 22 uses (Ft)- as the frequency of the transmission signal.
Since the frequency is set such that (Fr) = Δ, or the frequency is set such that (Fr) - (Ft) = Δ, the transmitting frequency and receiving frequency are uniquely determined by having a certain frequency difference. It is worshiped. In other words, if the transmission frequency belongs to a high frequency within the frequency band, the reception frequency will have a certain frequency difference lower than the transmission frequency, and if the transmission frequency belongs to a lower frequency, the reception frequency will have a fixed frequency difference compared to the transmission frequency. Frequency difference has higher frequency. Therefore, by detecting the frequency of the local oscillator 22 that determines the transmission frequency, it is possible to uniquely determine whether the reception frequency belongs to a high frequency or a low frequency. Therefore, by detecting the output of the local oscillator 22 with the detector 21, the output of either the first or second local oscillator 43, 44 is selected. Thereafter, the single low-frequency second intermediate frequency signal IFr 2 is converted into a baseband signal Bout through an amplifier 45, a filter 46, and a demodulator 47.

以上説明したように本発明によれば、フイルタ
素子等を交換することなく、前記決められた周波
数帯の送・受信周波数を任意に変更することので
きるマイクロ波多重無線装置が実現される。
As described above, according to the present invention, a microwave multiplexing radio device is realized that can arbitrarily change the transmission/reception frequency of the determined frequency band without replacing filter elements or the like.

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

添付図は本発明に基づくマイクロ波多重無線通
信方式を実施する装置の一実施例を示すブロツク
図である。 図において11は変調器、12,34,41は
それぞれ周波数変換器、13,33,36,46
はそれぞれフイルタ、14,32,35,45は
それぞれ増幅器、21は周波数検出器かあるいは
等価的に周波数を検出できる検出器、22,4
3,44はそれぞれ局部発振器である。
The attached figure is a block diagram showing one embodiment of a device implementing a microwave multiplex wireless communication system based on the present invention. In the figure, 11 is a modulator, 12, 34, 41 are frequency converters, 13, 33, 36, 46, respectively.
are filters, 14, 32, 35, and 45 are amplifiers, 21 is a frequency detector or equivalently a detector capable of detecting frequencies, and 22, 4 are respectively filters.
3 and 44 are local oscillators, respectively.

Claims (1)

【特許請求の範囲】 1 送信周波数及び受信周波数が予め定められた
周波数帯域内にあり、且つ送信周波数と受信周波
数との差が一定であり、一義的に決められている
マイクロ波多重無線システムに使用され、送信系
および受信系ならびにこれらと接続しているアン
テナ装置を有するマイクロ波多重装置において、 前記送信系には前記周波数帯域の幅の周波数よ
り1桁高い送信系中間周波数を送信周波数に周波
数変換するための送信周波数変換器と、局部発振
器と、該周波数変換器出力信号のうち前記周波数
帯域内の送信周波数だけ取り出せるように前記周
波数帯域を通過帯域とする送信帯域通過ろ波器を
もち、 前記受信系には受信周波数を前記周波数帯域の
幅の周波数より1桁高い第1受信系中間周波数に
変換するための第1受信周波数変換器と局部発振
器をもち、該局部発振器は該送信系の局部発振器
と共用し、 さらに該受信系には第1受信系中間周波数を第
2受信中間周波数に変換するための第2受信周波
数変換器と第1受信局部発振器および第2受信局
部発振器をもち、該第1受信局部発振器と該第2
受信局部発振器の周波数差を送信系の送信周波数
と受信系の受信周波数の周波数差の2倍に等しく
し、前記局部発振器の出力周波数によつて該第1
または第2の受信局部発振器の周波数を選択して
用いることを特徴とするマイクロ波多重無線装
置。
[Claims] 1. A microwave multiplex radio system in which the transmitting frequency and the receiving frequency are within a predetermined frequency band, and the difference between the transmitting frequency and the receiving frequency is constant and uniquely determined. In a microwave multiplexing device that is used and has a transmission system, a reception system, and an antenna device connected to these, the transmission system has a transmission system intermediate frequency that is one order of magnitude higher than the frequency of the width of the frequency band. It has a transmission frequency converter for conversion, a local oscillator, and a transmission bandpass filter whose passband is the frequency band so that only the transmission frequency within the frequency band can be extracted from the output signal of the frequency converter, The receiving system includes a first receiving frequency converter and a local oscillator for converting the receiving frequency to a first receiving system intermediate frequency that is one order of magnitude higher than the frequency of the width of the frequency band, and the local oscillator shared with the local oscillator, and the receiving system further includes a second receiving frequency converter for converting the first receiving system intermediate frequency to a second receiving intermediate frequency, a first receiving local oscillator, and a second receiving local oscillator; the first receiving local oscillator and the second receiving local oscillator;
The frequency difference of the receiving local oscillator is made equal to twice the frequency difference between the transmitting frequency of the transmitting system and the receiving frequency of the receiving system, and the output frequency of the local oscillator is
Alternatively, a microwave multiplex radio device characterized in that the frequency of the second receiving local oscillator is selectively used.
JP1936580A 1980-02-19 1980-02-19 Microwave multiplex radio device Granted JPS56116348A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP1936580A JPS56116348A (en) 1980-02-19 1980-02-19 Microwave multiplex radio device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP1936580A JPS56116348A (en) 1980-02-19 1980-02-19 Microwave multiplex radio device

Publications (2)

Publication Number Publication Date
JPS56116348A JPS56116348A (en) 1981-09-12
JPH0588014B2 true JPH0588014B2 (en) 1993-12-20

Family

ID=11997321

Family Applications (1)

Application Number Title Priority Date Filing Date
JP1936580A Granted JPS56116348A (en) 1980-02-19 1980-02-19 Microwave multiplex radio device

Country Status (1)

Country Link
JP (1) JPS56116348A (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2780713B2 (en) * 1987-11-27 1998-07-30 ソニー株式会社 Communication equipment

Also Published As

Publication number Publication date
JPS56116348A (en) 1981-09-12

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