JPS6062201A - Demultiplexer and multiplexer - Google Patents

Abstract

PURPOSE:To reduce the electric power loss of a signal to be multiplexed and demultiplexed by isolating frequency bands of transmission and reception channels connected to the same transmission line from one another. CONSTITUTION:When transmission channels 1, 3, and 5, and 2, 4, and 6 are regarded as transmission signal systems (a) and (b), equivalent electric lengths of the signal systems (a) and (b) viewed from the connection terminal 44a of a switch 44 for a manifold 47 allow the composite output of the signal systems to be supplied to the terminal 44a in the best state, and receive signals to be short- circuited. The switch 44 consists of a waveguide switch and connects the manifold 47 which connects a transmission channel A, receiving band-pass filter 118, and connection terminal 10 of an antenna to either of a manifold 45 which connects the channels 1-5 and a manifold 46 which connects the channels 2-6. Therefore, frequency bands of respective channels of the transmission systems are isolated from one another, so the electric power loss is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is used in a satellite-mounted communication device in the microwave and millimeter wave frequency bands, and in a communication device equipped with a plurality of communication systems such as a working communication system and a backup communication system, each communication system The present invention relates to a multiplexer/demultiplexer that effectively multiplexes or demultiplexes multiple communication signals.

A demultiplexer is located between the antenna section of a communication satellite and the transmitter/receiver section of communication equipment, and has the function of separating the transmitted and received signals, multiplexing a large number of transmitted signals, and guiding them to the antenna section. It has the function of splitting the received signal into multiple reception filters.

In conventional demultiplexers and multiplexers, a Terawave tube type is generally used, in which the receiving band filters of the working and standby transmission channels are both connected to one waveguide, and a manifold (multiple waveguides are connected to one common Terawave tube) is used. The branch waveguides were connected to form a three-dimensional circuit. FIG. 1 shows a block diagram of an example of a typical conventional demultiplexer/multiplexer commonly used. In the figure, 11-1
6 are transmission signals 101 to 10 of transmission channels 1 to 6, respectively.
60 input terminals, 17 is transmission signal a of transmission channel A
input terminal, +8 is the output terminal of the received signal, 9-digit manifold, 10 is the connection terminal with the antenna section, ], 11-1
16 is a bandpass filter configuring transmission channels 1 to 6;
17 is a bandpass filter constituting transmission channel A; 118
indicates a receiving band filter.

Terminals 11 to 17 are sent to France, Hakugo 101 to 106 and a.
is output through the entire manifold 9 to the connection terminal 10 with the antenna section. The received signal from the antenna section is input to the terminal 10, passes through the manifold 9'f, and is outputted from the output terminal 18 of the reception band filter. Here, transmission channels 1 and 3
．． 5 is in current use and 2°4.6 is in reserve.

FIG. 2 shows an example of the frequency arrangement of the transmitted signal and received signal in the conventional demultiplexer/multiplexer. In the figure, 19~
24 are pass characteristic lines of the bandpass filters 111 to 116, respectively;
5 is a pass characteristic line of the band filter 117, and 26 is a pass characteristic line of the band filter 118. As shown in this diagram, the transmission signal 10
When the bandwidth of channels 1 to 06 is constant and the channel spacing is narrow, a portion of the transmitted signals 101 to 106 also enters the channels adjacent to each channel, resulting in wasted transmission power. In addition, in the multiplexer/demultiplexer shown in FIG. 1, all of the working and standby channels are connected to one manifold 9, so the frequency characteristics of each bandpass filter influence each other and adjustment is not easy. Moreover, since the electrical length from the antenna connection end 10 is long, there is also the disadvantage that 7L of transmitted and received power is wasted.

An object of the present invention is to provide a demultiplexer/combiner with less power loss in signals to be combined or divided.

The configuration of the present invention combines signals output from a plurality of filters with mutually different center frequencies to a first terminal of a first transmission path, or divides a signal output from this first terminal to the filters. In the multiplexer, the second to n+l (n minus an integer of 2 or more) to which the filter is connected
a transmission line, and a switching device in which the first terminal of the first transmission line and the first terminals of the second to n+1 transmission lines are respectively connected to different terminals, the switch The device is characterized in that the first terminal of the first transmission line is connected to any one of the second to (n+1)th transmission lines in response to a switching control signal.

Next, the present invention will be described in detail with reference to the drawings.

FIG. 3 is a block diagram of an embodiment of the present invention, where 44 is a switch, 45 is a manifold that connects transmission channels 1 and 3.5, 46 is a manifold that connects transmission channels 2° and 4.6, and 47 is a transmission Channel A, receive bandpass filter //
l? , a manifold that connects the connection terminal IO with the antenna, and 48 and 49 represent short circuit plates, respectively. Here, transmission channels 1 and 3.5 are assumed to be transmission signal system A, and transmission channels 2 and 4.6 are assumed to be transmission signal system ports. The equally constrained electrical lengths of the signal system A and the signal system port viewed from the connection terminal 44a with the manifold 47 of the switch 44 allow the combined output of each signal system to be optimally supplied to the connection terminal 4.43. However, the signal received from the antenna is short-circuited. The switch 44 is a waveguide switch 9 and connects the manifold 47 to either one of the manifolds 45 or 46.

This connection is determined by a switching control signal applied to switch 44.

FIGS. 4 and 5 are frequency arrangement diagrams of the transmitter E system A and E, respectively. As is clear from these figures, the frequency bands of transmission channels 1 to 2 are the same as in the conventional duplexer shown in Figure 2. However, the 42 transmission signal threads are connected to a common transmission path at the same time. Because it won't happen,
The frequency bands of the transmit channels connected to the manifolds 45 and 46 are well separated from each other.

In the transmission signal system A, the switch 44 is connected to the manifold 45't.
When connecting to 47, transmit channel 1:
Transmission signals 101, 103° 105 of 3 and 5, respectively
is applied to the input terminals 11, 13.15, and the bandpass filter 1
11, 113, and 115, are collected and synthesized in the manifold 45, and are output from the connection terminal 44a of the changeover switch 44 to the manifold 47. The composite signal entering the manifold 47 from this connection terminal 44a is transmitted to the input terminal 17.
The input signal is combined with the transmission signal A through the bandpass filter 117 at the manifold 47 and output to the antenna connection terminal 10.

Transmission channel 2 of transmission signal system port, transmission signal 1 of 4.6
02, 104, 106, the switch 44 is the manifold 4
When connecting 6 to 47, input terminal 12゜14.1
When manually operated from 6, the band filter 112°114.
116, it is added to the manifold 46 and synthesized, and this synthesized signal No. 18 is output to the antenna connection terminal 1 () similarly to the transmission signal system A. The received signal eU received by the antenna is inputted from the antenna connection terminal 10, passes through the manifold 47, passes through the bandpass filter 118, and is outputted to the output terminal 18 of the reception signal 1g.

In this embodiment, if the transmission signal system A is used as the working transmission system and the transmission signal system port is used as the backup transmission system, the frequency bands of each channel in the working transmission system are sufficiently separated from each other.
Power loss is low, and so is the backup transmission system.

In addition, in the above-mentioned actual Llu example, even if there are only a plurality of transmission signal systems or a plurality of reception signal systems, a demultiplexer/multiplexer with little reception power loss can be realized.

In addition, in the embodiment shown in FIG. 3, there are two transmission signal systems, but one
It goes without saying that the present invention can be applied even if there are three or more transmission or reception signal systems.

As is clear from the above description, in the present invention, the frequency bands of transmission channels connected to the same transmission path are separated from each other, so that it is possible to reduce the loss of transmission signals by X months. The same can be said for the received signal,
The power loss in demultiplexing is

[Brief explanation of drawings]

Fig. 1 is a block diagram of a conventional demultiplexer/multiplexer, Fig. 2 is a frequency arrangement diagram of this demultiplexer/multiplexer, Fig. 3 is a block diagram of an embodiment of the present invention, and Figs. 4 and 5 are It is a frequency arrangement diagram of this example. 9.45, 46.47... Manifold)", 1
0...Antenna connection terminal, 11-17...
...Transmission signal input terminal, 18 ...Reception signal output terminal, 19-26 ... Passage characteristic line of band filter, 44 ... Switching device, 48゜49 ...Short circuit plate, 101-106. a... - Transmission signal, 11
1 to 118...Band filter. /15 Ara f Senno 7th prisoner "" 3■

Claims (1)

[Claims] In the demultiplexer/combiner that combines signals output from a plurality of filters having mutually different center frequencies to a first terminal of a first transmission line or divides a signal output from this first terminal to the filters, a second to (n+1)th (n is an integer of 2 or more) transmission paths to which the filter is connected, the first terminal of the first transmission path, and the second to (n+1)th transmission paths;
a switch in which terminals J] of the transmission line are connected to different terminals, respectively, and the switch switches the terminal J of the first transmission line in response to a switching control signal. A demultiplexer/multiplexer connected to any one of the second to (n+1)th transmission lines.