KR950005584B1 - Channel separating circuit for microwave freq. band - Google Patents

Abstract

This circuit separates or mixes several signals of different frequency bands without signal loss. It comprises: (i) an input terminal(A); (ii) an output terminal(B); (iii) a pass terminal(C) that transmits a channel signal except for a channel signal outputted to the output terminal; (iv) an isolation terminal(D) not transmitting a channel signal; (v) a microstrip transmit line(30) connecting the input terminal and the pass terminal; (vi) a microstrip transmit line(36) connecting the output terminal and the isolation terminal; and (vii) a pair of microstrip resonators(32),(34). The circuit separates channel easily because it has no power loss of channel signal transmitted to a channel separating circuit of next stage.

Description

Channel Separation Circuit in Micro Frequency Band

1 is a block diagram illustrating an embodiment of a channel separator composed of a plurality of channel separation circuits.

2 is a block diagram showing an embodiment of the channel separation circuit of FIG.

3 is a circuit diagram showing an embodiment of a channel separation circuit of a micro frequency band according to the present invention.

4 is a graph showing frequency characteristics at each terminal in the channel separation circuit shown in FIG.

* Explanation of symbols for main parts of the drawings

10, 12, 14: channel separation circuit 22: combiner

24: filter

30, 36: microstrip transmission line

32, 34: microstrip resonator

The present invention relates to channel separation in the micro frequency band, and more particularly to a channel separation circuit in a directional micro frequency band suitable for separating or mixing several signals in different frequency bands without loss of the signal.

A channel separator is a device that uses microwaves with frequencies in the range of about 1 to 10 GHZ, to separate channels of a specific frequency band from signals including several channels having different frequency bands.

1 is a block diagram showing an embodiment of a channel separator composed of a plurality of channel separation circuits, wherein four channel signals (fa + fb + fc + fd) having different frequency bands are divided into three channel separator circuits 10, (( 12), when input through the channel separator consisting of (14) in sequence, the channel signal fa is separated by a channel separation circuit 10 that can separate the channel signal of a specific frequency band, similarly the channel separation circuit Channel signals fb, fc, and fd are separated through (12) and (14).

FIG. 2 is a block diagram showing an embodiment of the channel separation circuit of FIG. 1. The channel separation circuit includes a combiner 22 and a filter 24. As shown in FIG.

In the channel separation circuit configured as described above, first, the combiner 22 separates the signal input from the input terminal A into two paths, one signal is the filter 24 and the other is the channel of the next stage. Deliver to a separate circuit.

At this time, the channel signal of a specific band is separated from the signal input to the filter 24.

However, in this conventional technique, the channel separation circuit reduces the power of the signal transmitted to the next stage by half (3dB) due to the characteristics of the combiner 22, and two circuits, the combiner 22 and the filter 24, are used. Therefore, there was a problem that occupies a relatively large area.

SUMMARY OF THE INVENTION An object of the present invention is to provide a channel separation circuit of a micro frequency band capable of separating a channel signal without reducing signal power with a relatively small area while having a performance of a combiner and a filter.

Hereinafter, with reference to the accompanying drawings an embodiment of the present invention for achieving the above object is as follows.

Referring to FIG. 3, FIG. 3 is a circuit diagram showing an embodiment of a channel separation circuit of a micro frequency band according to the present invention, wherein an input terminal A through which channel signals of a plurality of different frequency bands are input, and an input terminal An output terminal (B) in which only a channel signal of a specific frequency band is output among the plurality of channel signals input to (A), and a channel signal output to an output terminal (B) among a plurality of channel signals input to the input terminal (A). Passing terminal (C) for transmitting the remaining channel signal to the next stage, isolation terminal (D) which does not transmit any channel signal, and microstrip transmission line connecting input terminal (A) and passing terminal (C) (30), the microstrip transmission line (36) connecting the output terminal (B) and the isolation terminal (D), and the microstrip transmission lines (30) and (36) are arranged to be input to the input terminal (A). Predesign among channel signals of many different frequency bands Channel signal of the specific frequency band is different, and that the output to the output terminal (B), and also other channel signal comprises a microstrip resonator (32, 34) of the pair such that the output terminal to pass through (C).

Here, one end and the other end of each of the microstrip resonator 32 and the microstrip resonator 34 are separated from each of the microstrip transmission line 30 and the microstrip transmission line 36 by a predetermined interval, and the microstrip resonator The distance between one end of the 32 and one end of the microstrip resonator 34 is set to λ / 4, and the distance between the other end of the microstrip resonator 32 and the other end of the microstrip resonator 34 is 3λ / 4. Set it.

Is the wavelength of the channel signal to be separated by the output terminal (B).

Referring to Figure 4 of the present invention made as described above is as follows.

First, in the four terminals A, B, C, and D, various channel signals of different frequency bands are input to the terminal A as input terminals, and as output terminals to the terminal B, respectively. A channel signal of a specific frequency band is output among the plurality of channel signals, and the terminal signal is a channel separation circuit of the next stage except for the channel signal output to the output terminal B as a pass terminal (not shown in the drawing). It is connected to the next input terminal (not shown in the figure) so that it can be transmitted to the terminal, and the terminal D is an isolated terminal, and power of the channel signal is not transmitted at all.

Next, in the two microstrip resonators 32 and 34, the interval between the two ends of the side input through the input terminal A is maintained at λ / 4 intervals, and the two other ends of the side from which the signal is output. Maintain a spacing of 3λ / 4.

4 shows the frequency pass characteristic of the channel separation circuit seen from the terminal AB and the terminal AC. The input terminal A has a band pass characteristic with respect to the center frequency ω o when viewed from the output terminal B. From the output terminal A and the pass terminal C, it can be seen that the signal exhibits a band-blocking characteristic with respect to the center frequency omega.

The impedance of the microstrip transmitters 30 and 36 is Z, the impedance of the microstrip resonators 32 and 34 is Zo, the wavelength of the channel signal to be separated is λ, and the microstrip transmitter 30 When the capacitance due to the gap between the microstrip resonators 32 and 34 is "C", the channel signal to be separated into 2? = Π-2 ω oCZo (rad) of the microstrip resonators 32 and 34 is The frequency of is designed as (ω2-ω1) / ωo = 2ωo2C2ZZo / ω.

The operation of the channel separation circuit according to the present invention can be described using the overlapping principle of the right mode and the odd mode signals, and when a sine wave having a magnitude of + V is applied to the input terminal A, In the case of the mode, it is the same as applying a wave having the magnitude + V / 2 to the reference planes T1 and T4 of the input terminal A and the output terminal B at the same time.

In the case of the previous mode, the input terminal (A) and the output terminal (B) are equal to the sine wave of magnitude + V / 2 and -V / 2 applied to the same reference plane, respectively, and the right mode signal at the center frequency (ωo). Is applied, the right microstrip resonator 34 resonates and reflects the + V / 2 wave to the input terminal A and the output terminal B, respectively. The pre-mode signal is known by the left microstrip resonator 32 The signal of -V / 2 magnitude is reflected on the input terminal A, and the signal of + V / 2 magnitude is reflected on the output terminal B.

Therefore, at the center frequency, all the channel signals through the input terminal 1 are transmitted to the output terminal B to show band pass characteristics. If the resonant frequency is out of the channel signal, the channel signals through the input terminal A are passed through the terminal C as it is. Is delivered).

Therefore, only the channel signal of the required frequency band is sent to the output terminal B, and the channel signal of the remaining frequency band is transmitted to the pass terminal C with almost no loss, thereby enabling channel separation of the signal.

As described above, the present invention has almost no power loss of the channel signal transferred to the next channel separation circuit in the channel separation circuit, so that the channel separation at the next stage is easy, and the combiner and the filter function simultaneously. As a result, the structure is very simple, so that it is easy to integrate in a microwave integrated circuit (MIC).

Claims (1)

An input terminal A to which channel signals of a plurality of different frequency bands are input; An output terminal (B) for outputting only a channel signal of a specific frequency band among the plurality of channel signals input to the input terminal (A); Passing terminal (C) for transferring the remaining channel signal except the channel signal output to the output terminal (B) of the plurality of channel signals input to the input terminal (A) to the next stage; An isolation terminal D through which no channel signal is transmitted; A microstrip transmission line 30 connecting the input terminal A and the passing terminal C; A plurality of microstrip transmission lines 36 connecting the output terminal B and the isolation terminal D, and the microstrip transmission lines 30 and 36 to be input to the input terminal A; A pair of microstrip resonators 32, 34 for outputting a channel signal of a specific frequency band from the channel signals of different frequency bands to the output terminal B and the remaining channel signal to the pass terminal C. And one end and the other end of each of the microstrip resonators 32 and 34 are separated from each of the microstrip transmission lines 30 and 36 by a predetermined interval, and the microstrip The distance between one end of the resonator 32 and one end of the microstrip resonator 34 is set to λ / 4, and the distance between the other end of the microstrip resonator 32 and the other end of the microstrip resonator 34 is 3λ. And λ is a wavelength of the channel signal to be separated by the output terminal (B).