JPH1155157A - Antenna multicoupler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an antenna multicoupler in which a reception section of a radio equipment is surely protected by minimizing an output of the radio equipment, when an excess input power to a reception section is detected for suppressing supply of power to the reception section of the radio equipment. SOLUTION: A radio equipment 3 allows a transmission section Tx to provide an output of a signal with 5 W that is an input power condition of a power amplifier 2 to the amplifier 2. The output signal from the transmission section Tx is amplified into 50 W at the power amplifier 2, and the amplifier signal is outputted to an antenna. In the case that an antenna is open or a power of a reflected wave reaches 1 W or over and a power detection section in the antenna multicoupler 1 detects a power in excess of a prescribed power, an output voltage adjustment circuit of the radio equipment 3 is controlled so as to forcibly suppress the output to be 0.1 W or below. The output to the power amplifier 2 is 1 W or below through a similar control, and the input power to a reception section Rx of the radio equipment 3 immediately reaches 1 W or below to surely prevent the reception section Rx from being deteriorated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circulator-type antenna duplexer, and more particularly, to protection of a radio receiver.

[0002]

2. Description of the Related Art A conventional antenna duplexer of this type is described below.
This will be described with reference to the block diagram shown in FIG. In FIG. 2, 1 is a circulator type antenna duplexer, 2 is 50
A power amplifier of up to 70 W, 3 is a time-division simultaneous transmission / reception radio apparatus using one frequency, Tx of the radio apparatus 3 is a transmitting section, and Rx is a receiving section. Here, since the wireless device 3 has to repeat transmission and reception alternately in a very short cycle, a mechanical relay or the like cannot be used for switching between transmission and reception. Since the switching diode does not have a high frequency and a large capacity, when a transmission output power of 50 W class is required, an external power amplifier 2 is used as shown in FIG. 2 and a circulator type antenna duplexer is used. 1 was used to construct a large-capacity wireless device. In the figure, the radio 3 outputs a signal of 5 W which is the input power condition of the power amplifier 2 from Tx. The output signal from the Tx is output by the power amplifier 2 to 50
It is amplified to W and output to the antenna. Here, for example, when the antenna is open or the reflected wave is 1 W or more,
RL is determined by the power detector provided on the receiving line of the antenna duplexer.
, The contact of which disconnects the connection of the wireless device 3 to the receiving unit, switches to the terminating resistor side of R, and protects the receiving unit.

[0003]

However, in the configuration in which the receiving section of the wireless device is separated by a coaxial relay as in the above-mentioned prior art, it takes about 10 msec until an excessive input is detected and the relay operates. An excessively high power signal is supplied to the receiving unit of the wireless device, which may deteriorate the receiving circuit.
An object of the present invention is to solve this problem and to provide an antenna duplexer that can surely protect a receiving unit of a wireless device.

[0004]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention makes it possible to control a transmission output power adjusting circuit of a radio unit on the antenna duplexer side and to detect excessive input power to a receiving unit. In this case, the output of the wireless device is set to the minimum value, and the power supplied to the receiving unit of the wireless device is suppressed.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the block diagram of FIG. In FIG. 1, 1 is a circulator type antenna duplexer, 2 is 50
A power amplifier of up to 70 W, 3 is a time-division simultaneous transmission / reception radio apparatus using one frequency, Tx of the radio apparatus 3 is a transmitting section, and Rx is a receiving section. Normally, the wireless device 3 outputs a 5 W signal of the input power condition of the power amplifier 2 from Tx. The output signal from Tx is amplified to 50 W by the power amplifier 2 and output to the antenna. Here, for example, when the antenna is open or the reflected wave becomes 1 W or more and the power detection unit in the antenna duplexer 1 detects power exceeding a predetermined value, the output power adjustment circuit (APC) of the wireless device 3 is controlled. Then, the output is forcibly reduced to 0.1 W or less. By performing such control, the output to the power amplifier 2 becomes 1 W or less, the input power to the receiving unit of the wireless device 3 immediately becomes 1 W or less, and the deterioration of the receiving unit can be reliably prevented.

[0006]

As described above, according to the present invention, the receiving section of the radio can be reliably protected, and the power detecting section of the receiving section provided in the conventional antenna duplexer can be used to realize the protection of the radio. In controlling the output power adjustment circuit, the coaxial relay, the terminating resistor, and the like, which have been conventionally required, can be omitted, so that the antenna duplexer can be reduced in size and cost.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration example of a conventional antenna duplexer.

[Explanation of symbols]

1: circulator type antenna duplexer, 2: power amplifier, 3: radio.

Claims (1)

[Claims] In a circulator type antenna duplexer, when it is detected that a signal power supplied to a receiving unit of a wireless device exceeds a predetermined value, the transmitting output power of the wireless device is reduced, and the receiving unit is operated. An antenna duplexer characterized by being configured to protect.