KR20000041979A - Automatic device for adjusting gain of micro wave receiver - Google Patents

Abstract

PURPOSE: An automatic gain adjustor of a micro wave receiver is provided to receive an optimal receiving sensibility of a micro wave through the automatic gain adjustor, without considering external surrounding change in a communication device. CONSTITUTION: An automatic gain adjustor of a micro wave receiver comprises a receiving level detector(50), a microcomputer(60), and an amplifying controller(70). The receiver has a coupler(10), a duplexer(20), a micro wave amplifier(30), an Automatic Gain Controller(AGC)(40). The detector(50) converts to output a signal level of a micro wave extracted from the coupler(10) into a Direct Current(DC) level. The microcomputer(60) outputs a control signal for adjusting amplification corresponding a difference, by comparing the DC level with an optimal level supplied and stored to an internal Analog to Digital port. The amplifying controller(70) outputs the control signal to the micro wave amplifier(30). The coupler(10) matches to extract the micro wave received from an antenna without power loss. The duplexer(20) receives/transmits the micro wave with bidirectional separation. The micro wave amplifier(30) amplifies to output the micro wave. The AGC(40) controls an output signal with feedback without changing to a fixed level.

Description

Automatic gain controlling apparatus of microwave communication system

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic gain adjusting device of a microwave receiver. In particular, in a communication device using a microwave having characteristics very sensitive to an external environment, the reception sensitivity of the microwave is adjusted through automatic gain adjustment regardless of such an external environment change. The present invention relates to an automatic gain adjusting device of a microwave receiver that can be optimally maintained.

In general, microwaves have a frequency range ranging from about 1 GHz to 300 GHz in a broad sense, in which the wavelength of the electromagnetic waves is close to the size of the equipment to be handled, corresponding to 30 cm to 1 mm. As a result, normal paired wires are inadequate as means for transmitting low-frequency waves, and transmission lines specific to the microwave region are used.

In addition, in the case of applying the microwave to the wireless communication, the microwave in the frequency band of 3GHz to 30GHz is used, and the relay system includes a heterodyne relay method, a detection relay method, and a direct relay method. The weak microwaves are amplified and raised to a specified level of output and transmitted from the transmitting antenna to the next station.

On the other hand, the microwave is attenuated severely due to the influence of atmospheric changes during the propagation of free space, and the call quality using the microwave is a very important problem, so countermeasures have to be prepared.

In particular, by adopting a large-capacity digital modulation scheme, the economy, reliability, and quality deterioration have been overcome to some extent, but in this frequency band, there is a problem in that the relay interval is shortened to form a stable line due to large attenuation of radio waves due to rainfall.

1 is a block diagram of a general microwave receiver, and includes a coupler 10, a duplexer 20, a microwave amplifying unit 30, and an AGC unit 40.

In this configuration, the coupler 10 extracts and outputs microwaves, which are induced and input from the antenna ANT, without power loss.

In addition, the duplexer 20 is a coupler for efficiently radiating microwaves without mutual interference by sharing antennas with two transceivers having different bands.

In addition, the microwave amplification unit 30 is a means for amplifying the power of the microwave applied from the duplexer 20, and includes a traveling wave tube, a silicon bipolar transistor, an imperial diode, and the like, and recently, gallium arsenide (GaAs) Use a field effect transistor or use a metal-ceramic traveling waveguide in a long-distance large-capacity system.

The AGC (automatic gain control) unit 40 prevents the output from fluctuating in response to a change in the input level due to fading of the microwave applied from the microwave amplifying unit 30 as the automatic gain adjusting unit.

Meanwhile, in the microwave receiver having the above-described configuration, microwaves are induced through the antenna ANT and transmitted to the microwave amplification unit 30 through the coupler 10 and the duplexer 20.

At this time, the microwave amplifying unit 30 amplifies and outputs the applied microwave by a predetermined predetermined amplification degree regardless of the signal strength, and the AGC unit 40 is amplified by the microwave amplifying unit 30 and output. The signal strength of the microwave is controlled to be kept constant.

However, as described above, the microphone wave is very sensitive to the environmental conditions of the external spatial medium, so when the external environment changes suddenly due to rain or cold, the received sensitivity is weak and the desired call quality cannot be obtained. This will occur.

Accordingly, the present invention is to propose a method for maintaining a constant call quality by receiving at a certain level or more sensitivity regardless of the external environment when receiving a microwave.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object thereof is to obtain a desired call quality by maintaining an optimal reception sensitivity regardless of an external environment as a transmission medium when receiving a microwave in a microwave receiver. In addition, the present invention provides an automatic gain adjusting device of a microwave receiver to extend a relay distance.

1 is a block diagram of a typical microwave receiver.

2 is a block diagram of a receiver including an automatic gain adjustment apparatus of a microwave receiver according to the present invention.

<Explanation of symbols for the main parts of the drawings>

10: coupler 20: duplexer

30: microwave amplification unit 40: AGC unit

50: reception level detector 60: microcomputer

70: amplification control unit

The automatic gain adjustment apparatus of the microwave receiver according to the present invention includes a coupler for matching and extracting microwaves received from an antenna ANT without power loss, a duplexer for bidirectionally separating and transmitting microwaves from the coupler, and a duplexer A microwave receiver comprising a microwave amplifying unit for amplifying and outputting microwaves from an AGC unit, and an AGC unit for controlling feedback of an output signal to a predetermined level without change based on an input / output signal of the microwave amplifying unit, the extractor being extracted from the coupler. A reception level detector that detects the signal level of the microwave and converts the signal into a DC level, and outputs the DC level from the reception level detector to an internal A / D port to compare the optimum level with a pre-stored optimal level. Amplification Control And an amplification controller for outputting a signal to the microwave amplifier and a control signal for amplifying control in response to the control signal of the microcomputer.

The above objects and various advantages of the present invention will become more apparent from the preferred embodiments of the invention described below with reference to the accompanying drawings by those skilled in the art.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a block diagram of an automatic amplification adjustment device of a microwave receiver according to the present invention, which includes a coupler 10, a duplexer 20, a microwave amplifier 30, an AGC unit 40, and a reception level detector 50. ), The microcomputer 60 and the amplification control unit 70 is configured.

In the figure, the coupler 10 is matched with the antenna ANT and outputs microwaves applied from the antenna ANT H without power loss.

The duplexer 20 uses a bidirectional transceiver to share the antenna ANT to radiate microwaves efficiently without mutual interference.

In addition, the microwave amplification unit 30 is a means for amplifying the power of the microwave applied from the duplexer 20, in particular, the amplification process to output the microwave applied from the duplexer 20 to a predetermined amplification, which will be described later Microwaves applied to the amplification degree corresponding to the control of the control unit 70 is amplified and output.

On the other hand, the AGC unit 40, as an automatic gain adjusting means, prevents the output from changing according to a change in the input level resulting from fading of the microwaves applied from the microwave amplifying unit 30 and the like.

Then, the reception level detector 50 detects the level of the microwave signal extracted from the coupler 10 without power loss, converts it to a DC level, and applies it to the A / D port of the microcomputer 60 which will be described later.

In addition, the microcomputer 60 is a DC level signal representing the signal level of the received microwave signal applied from the reception level detector 50 through the internal A / D port to compensate for the reception sensitivity generated on the microwave transmission. Is compared with a preset reference level stored therein and outputs a control signal for amplification adjustment corresponding to the difference.

On the other hand, the amplification control unit 70 converts the control signal for amplification control applied from the microcomputer 60 into an analog signal and applies the converted control signal to the microwave amplification unit 30.

Next, an operation process of the automatic gain amplifier of the microwave receiver according to the present invention having the above-described configuration will be described in detail.

First, when the microwave is input through the antenna ANT, the coupler 10 separates the power of the microwave. That is, the coupler 10 extracts the microwaves without power loss from the input of the microwaves induced through the antenna ANT.

Next, the microwave extracted through the coupler 10 is applied to the microwave amplifying unit 30 through the duplexer 20.

Then, the microwave amplification unit 30 amplifies and outputs the microwaves applied from the duplexer 20 by a predetermined amplification. At this time, the AGC unit 40 is configured to output the microwaves from the microwave amplifying unit 30. The feedback control of the predetermined signal level component to the microwave input to the microwave amplifying unit 30 is prevented from changing the output of the microwave amplifying unit 30.

In addition, the microwave output from the coupler 10 without power loss is applied to the reception level detector 50. In this case, the reception level detector 50 detects the signal level of the microwave applied from the coupler 10 and detects the signal level. The level is converted into a DC level signal and applied to the A / D port of the microcomputer 60.

Then, the microcomputer 60 receives the DC level signal applied from the reception level detector 50 through the internal A / D port, converts the signal into a digital signal, and compares the converted digital signal with a preset reference level.

In this case, the preset reference level is a stored level for optimally maintaining the call quality, and the microcomputer 60 calculates a difference between the reference level and the reception level applied from the reception level detector 50. In order to amplify the reception sensitivity in response to the difference, an amplification control signal corresponding to the calculated difference is applied to the amplification control unit 70.

Then, the amplification control unit 70 outputs an analog DC voltage for adjusting the amplification degree of the microwave amplification unit 60 based on the amplification control signal applied from the microcomputer 60.

Next, the microwave amplifier 60 amplifies and outputs the power of the microwave applied from the duplexer 20 by varying the degree of amplification based on the analog DC voltage applied from the amplification control unit 70.

Accordingly, when the present invention is applied, high quality communication can be performed regardless of external environmental conditions in a communication system using microwaves.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

As described above, according to the present invention, when performing microwave communication that reacts sensitively to the external environment, it is possible to make a high quality call regardless of the external environment such as rainfall, and to increase the relay distance. have.

Claims (1)

Coupler 10 for matching and extracting microwaves received from the antenna ANT without power loss, a duplexer 20 for bidirectionally separating and transmitting the microwaves from the coupler 10, and the duplexer 20 Microwave including a microwave amplification unit 30 for amplifying and outputting a microwave and the AGC unit 40 for feedback control without change to a predetermined level based on the input and output signals of the microwave amplification unit 30 For wave receiver, A reception level detector (50) for detecting a signal level of the microwave extracted from the coupler (10), converting the signal into a DC level, and outputting the signal; A microcomputer (60) which receives the DC level from the reception level detector (50) to an internal A / D port and compares it with a pre-stored optimum level and outputs an amplification adjustment control signal corresponding to the difference; And an amplification control unit 70 outputting a control signal for amplifying control of the microwave amplifying unit 30 to the microwave amplifying unit 30 in response to the control signal of the microcomputer 60. Automatic gain amplification adjustment device of the microwave receiver.