JPH02207626A - Microwave repeater - Google Patents

Abstract

PURPOSE:To selectively transmit a signal in the arbitrary direction of incoming and outgoing by a simple frequency modulation system even when shift frequencies in incoming and outgoing direction are different by providing the transmitter of an auxiliary signal such as the monitor information of a station itself together with the repeating operation of a main body. CONSTITUTION:Frequency conversion is executed by a frequency mixer 5(7) to a received signal guided from one of a pair of devices 3 and 4 shared for transmission and reception and the signal is amplified up to a necessary level by a microwave amplifier 6(8). After that, this signal is guided to the other one of the devices 3(4) shared for transmission and reception as a transmission signal. As a local oscillation source for frequency conversion, frequencies, for which the frequencies of a main oscillator 10 and an auxiliary oscillator 9 with the different frequencies are added and subtracted by a frequency mixer 11, are respectively used and frequency modulation can be loaded through a switcher 16, which can mutually select either a reverse phase or the same phase, to these two oscillators. Thus, even when the shift frequencies in the incoming and outgoing direction are different, the transmission function can be provided in the arbitrary direction of the incoming and outgoing.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a microwave repeater used in a microwave communication line, and in particular to a frequency shift type microwave direct repeater, in which main signal relay operation is performed. The present invention also relates to a microwave repeater having a function of transmitting auxiliary signals such as monitoring information of its own station.

[Conventional technology]

Conventionally, this type of frequency shift type microwave direct repeater has either one oscillation source common to uplink/downlink as a local oscillator for frequency shifting (in the case of the same shift frequency for upper and lower lines), or 2 independent upstream/downstream lines
The conventional method was to have two oscillation sources (upper and lower, with the same shift frequency, or upper and lower, with different shift frequencies).

[Problem to be solved by the invention]

In the conventional microwave direct repeater described above, when the uplink/downlink shift frequencies are different (particularly in a multi-directional multiplex microwave wireless communication system, etc., in order to avoid radio frequency interference, the relay station shifts the shift frequency in the up and down directions. Since two oscillators with different shift frequencies are required, the structure becomes complicated and the device becomes expensive.

[Means to solve the problem]

The microwave repeater of the present invention frequency-converts a received signal guided from one of a pair of transmitting/receiving duplexers each equipped with a band-pass p-wave device and a circulator corresponding to each of the transmitting and receiving frequencies, and amplifies it to a required level. Later, in a frequency shift type microwave direct repeater configured to guide this as a transmission signal to the other of the pair of duplexers, the frequencies of the main excavator and auxiliary oscillator with different frequencies are used as local oscillation sources for frequency conversion. Using a frequency mixer, the added and subtracted oscillators are used, and frequency modulation can be applied to these two oscillators via a switch that allows you to select either the opposite phase or the same phase. It is something.

[Function] The present invention has a function of transmitting auxiliary signals such as monitoring information of its own station as well as a main signal relay operation.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

The figure is a block diagram showing one embodiment of the present invention.

In the figure, 1 is an upward direction transmitting and receiving antenna, 2 is a downward direction transmitting and receiving antenna, and 3 and 4 are bandpass filters 3-1, 3-2, circulators 3-3, and bandpass filters corresponding to each of the transmitting and receiving frequencies. 4-1. A pair of duplexers including 4-2 and a circulator 4-3, 5 a frequency mixer, 6 a microwave amplifier, 7 a frequency mixer,
8 is a microwave amplifier.

A pair of transmitting/receiving duplexers 3, each including bandpass filters 3-1, 3-2 (4-1, 4-2) and a circulator 3-3 (4-3) corresponding to each of the transmitting and receiving frequencies, 4
The received signal guided from one of the transmitter/receivers 3 (4) is frequency-converted by the frequency mixer 5 (7), amplified to a required level by the microwave amplifier 6 (8), and then used as a transmit signal to be transmitted to the pair of transmitter/receiver duplexers 3 (4). ), and these constitute a frequency-shifted microwave direct repeater.

9 is the main oscillator (fl), 10 is the auxiliary oscillator (f4), 1
1 is a frequency mixer, 12 is a band pass filter (S30F4
), 12 is a band pass filter (fs f4), 14 is a modulation signal input terminal, 15 is an inverter, and 16 is a switch.

Then, as a local oscillation source for frequency conversion, the frequencies of the main excavator 9 and the auxiliary oscillator 10 having different frequencies are added and subtracted by the frequency mixer 11, respectively, and
These two oscillators are configured so that frequency modulation can be applied to them via a switch 16 that can select either mutually opposite phase or in-phase.

Next, the operation of the embodiment shown in this figure will be explained.

First, f is the receiving frequency in the downward direction coming from the upper station, which is shifted to a frequency f2' and retransmitted to the lower station. On the contrary, fl is an upstream reception frequency arriving from a lower station, which is shifted to a frequency fl1 and retransmitted to an upper station. On the other hand, fl is the main oscillation source of the shift frequency, f4 is the auxiliary oscillation source, and in the example shown in the figure, (f3+f4) is the shift frequency in the downward direction, and (f, ~ f4) is the shift frequency in the upward direction. . That is, frequency 'l+'l' Ill
+'1Zf3 +f4 has the following relationship.

1) f2' = fl + (fB + f4) II)
r,' = r, ±(fl-f4)Ill) f,'
-f1=f2'-f2=f3IV) f2-fl=f2'
−f,' = f4 and the receiving frequency f1 which is the signal received by the uplink transmitting/receiving antenna 1 facing in the upstream direction.
has one circulator 3-3 and a center frequency of f
It passes through a duplexer 3 consisting of two band transmitters 3-1 and 3-2, 1 and f1', and is added, for example, to the downstream shift frequency Cf3+f<) in a frequency mixer 5. After being amplified to the required level by the microwave amplifier 6, there is also a circulator 4-3 and two bandpass filters 4-1.4- with center frequencies f,',f.
2, the frequency is f2'
Only the signals are transmitted via the transmitting/receiving antenna 2 in the downward direction. Here, although the explanation will be omitted, the same operation is performed in the up direction as well.

That is, the received signal f! →f2, shift frequency (fs+
f4) → (fs) - (f4), transmission signal f2' → f1'
, frequency mixer 5→7, and microwave amplifier 6→8.

Next, the shift frequency component is generated by mixing the output signals of the main oscillator 9 with an oscillation frequency fs and the auxiliary oscillator 10 with an oscillation frequency f4 in a frequency mixer 11, and then in a bandpass p-wave generator 12 (
The component of f3+f4) is filtered by the bandpass filter 13 into (fs
It is obtained by extracting the component of f4). Further, the main oscillator 9 can be frequency modulated by a control signal inputted through the modulation signal input terminal 14, and the control signal can also be applied to the auxiliary oscillator 10 as it is by the switch 16. Alternatively, frequency modulation can be applied by inverting the signal using an inverter 15 and adding the signal.

Here, if the modulation sensitivities of the main oscillator 9 and the auxiliary oscillator 10 are adjusted to be equal, the switch 16 is connected to the output of the inverter 15, for example, as shown in the embodiment of the figure. In this case, modulation is applied to fs and f4 in opposite phases to each other, so the modulation signal input terminal 14
The control signal from the terminal is canceled in the downward direction and is transmitted only in the upward direction. Also, on the contrary,
When the switch 16 is switched, modulation is applied to fs and f4 in the same phase, so that the upstream direction of the control signal is canceled and the control signal is transmitted only in the downstream direction.

〔Effect of the invention〕

As explained above, the present invention has the function of transmitting auxiliary signals such as own station monitoring information in addition to the main signal relay operation, so that even when the vertical shift frequencies are different, an expensive shift frequency mixer is not required. There is no need to prepare two types of oscillators; one main oscillator, one auxiliary oscillator, which is inexpensive because its oscillation frequency is relatively low, and the outputs of these two types of oscillators are simply mixed. It can be configured with a simple band-pass filter to extract the necessary components, and is relatively inexpensive compared to conventional methods. Moreover, it can generate shifted frequency components by adding and subtracting the outputs of the main and auxiliary oscillators. By utilizing this fact, for example, a state monitoring signal of a microwave relay station can be selectively transmitted in any up/down direction using a simple frequency modulation method. .

[Brief explanation of the drawing]

The figure is a block diagram showing one embodiment of the present invention. 1...Uplink transmitting/receiving antenna, 2...Downward transmitting/receiving antenna, 3...Transmitting/receiving duplexer, 3-1.3
-2...Band pass p-wave device, 3-3...Circulator, 4ken...Transmitter/receiver duplexer, 4-1.4-2...
・Band pass filter, 4-3...Circulator, 5
...Frequency mixer, 6...Microwave amplifier,
7... Frequency mixer, 8... Φ microwave amplifier, 9... Main oscillator, 10... Auxiliary oscillator, 11
・・・Frequency mixer, 12.13・φ・・bandpass p
14...Modulation signal input terminal, 15...φ inverter, 16...Switcher.

Claims (1)

[Claims] After converting the frequency of the received signal led from one of the pair of duplexers equipped with a bandpass filter and a circulator corresponding to each of the transmitting and receiving frequencies and amplifying it to a required level, this is used as the transmitting signal to transmit the signal to the pair of transmitting/receiving frequencies. In a frequency shift type microwave direct repeater configured to lead to the other side of the transmitter/receiver, the frequencies of the main oscillator and auxiliary oscillator with different frequencies are added and subtracted by a frequency mixer as a local oscillation source for frequency conversion. use each item,
A microwave repeater characterized in that the two oscillators are configured so that frequency modulation can be applied to them via a switch that can select either mutually opposite phase or in-phase.