Transmitter/Receiver apparatus with an antenna for use of both signal transmission and reception

摘要

An object of the present invention is to provide a transceiver-design-change-no-required transmitter/receiver apparatus with an antenna for use of both signal transmission and reception of a type extending a radio coverage under the regulated EIRP by using a single antenna having a higher gain than the antenna initially-planned to use with the transceiver. A transmitter/receiver apparatus 100 is provided with a transmitting signal only-path 107 and a received signal only-path 108. A transmitting signal heads for an attenuator 104 through a passage constituted by the transmitting signal only-path 107 via a circulator 132. After being attenuated therein, the transmitting signal heads for a transmitting/receiving antenna 101 via a circulator 131. A received signal, on the other hand, heads for a transceiver 102 through a passage constituted by the received signal only-path 108 via the circulators 131 and 132. As the attenuator 104 attenuates the transmitting signal, no matter how a gain of the transmitting/receiving antenna 101 is high, the level of the transmitting signal to be outputted stays within the level applicable to the regulated EIRP.