JPH04351021A - Synthesis branch device - Google Patents

Abstract

PURPOSE:To reduce the mechanical size by eliminating the need for a special power supply and to improve the reliability of the entire earth station by eliminating the need for a power supply for the common section. CONSTITUTION:A synthesis branching device having plural IDU(Indoor units) 1-1-1-3 each having a MODEM, one ODU(Outdoor unit) 11 having a high frequency section, an antenna section 12 allowing a transmission reception radio wave with a satellite to radiate, and a control circuit 1 connecting to the ODU and making transmission reception with a transmission signal, a reception signal and a control signal is provided with a control means which extracts a DC signal included in a control signal component in the control circuit 1, supplies the DC signal to the ODU as a power supply and uses it as a power supply for its own power supply.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a synthesis/demultiplexing device, and in particular to an IDU (Indoor unit), an ODU (
In a small earth station (usually referred to as a VSAT) equipped with an out door unit (out door unit) and a very small antenna unit, it is connected as an interface between many IDUs and one ODU, and connects many carriers of the IDU to one OD.
The present invention relates to a combining and demultiplexing device for transmitting and receiving in the U.

0002

[Prior Art] As shown in FIG. 3, a conventional VSAT has a configuration that combines and demultiplexes an IDU equipped with three modems and transmits it to an ODU equipped with a high-frequency section. It consists of a synthesis/demultiplexing device main body 22 that serves as an interface. In FIG. 3, three IDUs 1-1 to 1-3 are input to the synthesis/demultiplexing device main body 22 through interface cables 10-1 to 10-3. Combiner/demultiplexer main body 2
2, multiplexers 6-1 to 6-3 each IDU1-
Only the transmission signals from 1 to 1-3 are taken out, and the three waves are further combined in a transmission signal combiner 7. Regarding the received signal,
After the received signal is split into three parts by the reception signal splitter 8, the signals are input to the multiplexers 6-1 to 6-3. Also, each IDU1-
Control signals from 1 to 1-3 are input to a control signal synthesizer 20, which controls the output level of the ODU 11 to a specified value. The output of the transmitting signal combiner 7, the input of the received signal demultiplexer 8, the output signal of the control signal combiner 20, and the output voltage of the power supply 21 are combined and demultiplexed by the multiplexer 9 to form a single waveform. ODU11 through coaxial cable 9A
It had the ability to transmit data to

0003

[Problems to be Solved by the Invention] The conventional synthesis/demultiplexing device described above requires a power source for operating the control signal synthesis circuit 20 necessary for the synthesis/demultiplexing device main body 22 and for supplying the DC voltage for the ODU 11. Must have 21. Therefore, the device itself becomes large. On the other hand, since a large number of IDUs are connected to this device itself, the reliability of this device is mostly determined by the reliability of the power supply, and there are drawbacks that reduce the reliability of this VSAT earth station. there were.

0004

[Means for Solving the Problems] The synthesis/demultiplexing device of the present invention has a plurality of IDUs (Indoor Units) each having a modulator/demodulator.
nit) and one ODU (Out
door unit), an antenna section that emits radio waves transmitted and received from the satellite, and a control circuit that is connected between the plurality of IDUs and the ODU and exchanges transmission signals, reception signals, and control signals. In the apparatus, extracting a DC signal included in a control signal component in the control circuit,
It has a control means that supplies the DC signal to the ODU as a power source and also uses it as a power source for its own control circuit.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings. FIG. 1 shows a VSA including a combining/demultiplexing device according to an embodiment of the present invention.
FIG. 2 is a block diagram of the main part of the control circuit 1 of this embodiment. In the embodiment of FIG. 1, the same reference numerals as in the conventional example of FIG. 3 have the same functions and configurations. That is, in this embodiment, the power source 21 of the conventional example is not required, and the power source is generated in the control circuit 1 from the DC signals inputted from the IDUs 1-1 to 1-3.

Next, the configuration and operation of the control circuit 1 of this embodiment will be explained with reference to FIG. Each output of multiplexers 6-1 to 6-3 is input to control circuit 2. The control circuit 2 detects the control signal of each input signal and outputs O according to the number of transmitted carriers.
It operates to control the automatic level control circuit of ODU 11 by creating control data to change the output level of DU 11 and interfacing the control data signal to ODU 11. On the other hand, multiplexers 6-1 to 6-3
By combining the inputs through the diodes 5A to 5C, the low frequency components output from the IDUs 1-1 to 1-3 are combined. This composite signal is passed through a low-pass filter 3, whereby the control signal is attenuated and only a DC signal 3A is obtained. The DC signal 3A and the output signal of the control circuit 2 described above are combined by a combiner 4. On the other hand, the DC signal 3A is also used as the operating voltage of the control circuit 2.

As described above, each IDU 1-1 to 1-3
Since the control circuit 2 can also operate using the DC voltage that was used for operating the ODU 11, there is no need to provide a special power source for the main unit 13 of the combining/demultiplexing device.

[0008]

As explained above, the present invention eliminates the need for a special power source by providing a control circuit in the synthesis/demultiplexing device, so that its mechanical dimensions can be reduced, and
Since there is no power source in the common area, it has the effect of increasing the reliability of the entire earth station. Furthermore, in the present invention, since the DC power supply voltages of each IDU are combined using diodes and operated in parallel,
This also has the effect that even if the power supply of one of the IDUs fails, communication can continue with the normal IDU.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram including a combining/demultiplexing device according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a main part of a control circuit of this embodiment.

FIG. 3 is a configuration diagram including a conventional combining/demultiplexing device.

[Explanation of symbols]

1, 2 Control circuit 3 Low-pass filter 4 Combiners 5A to 5C Combining diodes 6-1 to 6-3, 9 Multiplexer 7
Transmission signal combiner 8 Reception signal demultiplexer 1-1 to 1-3 IDU 11 ODU 12 Antenna 13 Synthesis/demultiplexer main body 21 Power supply

Claims (2)

[Claims] Claim 1: A plurality of IDUs (IDUs) each having a modem and a modem.
n door unit) and 1 with a high frequency section.
an antenna section that emits radio waves transmitted and received from the satellite; and a control circuit that is connected between the plurality of IDUs and the ODU and exchanges transmission signals, reception signals, and control signals. In the combining/demultiplexing device, the control means extracts a DC signal included in a control signal component in the control circuit, supplies the DC signal to the ODU as a power source, and also uses the DC signal as a power source for a self-control circuit. A combining/demultiplexing device comprising: 2. The control means comprises a multiplexer into which the signals of the plurality of IDUs are respectively input, a diode which combines the output signals of the multiplexer, and a low-pass filter which outputs a DC component from the output signal of the diode. ,
2. The combining/demultiplexing device according to claim 1, further comprising a multiplexer that combines the control signal extracted by the control circuit and the DC component.