Abstract: A radio communication apparatus performing time division duplex alternately switching a transmission period and a reception period by time dividing an identical frequency, includes the steps of: detecting a transmission signal to be transmitted to the antenna so as to perform radio transmission from an antenna commonly used for transmission and reception; and calculating a deviation time between the detection timing of the detected transmission signal and a preset reference timing, and for controlling switchover timing between the transmission period and the reception period based on the deviation time.

Abstract: A first output device has a first port, a second port, and a third port, and outputs from the second port a transmission signal supplied to the first port. A second output device has the same ports as those of the first output device, outputs from the second port the transmission signal supplied to the first port from the first output device, and outputs from the third port a reflected wave supplied to the second port from an antenna. A phase shifter inverts a phase of a signal output from the third port of the first output device. An adder adds a signal output from the third port of the second output device and a signal output from the phase shifter.

Abstract: There is provided a transmitter receiver apparatus in which a directional coupler and single pole double throw (SPDT) switches are includes on the reception side. In the directional coupler, a reception signal is inputted and split into two signals having phases different from each other by 90° and the two split signals are outputted to SPDTs. Each of the SPDTs outputs each of the split signals to an output terminal connected to an amplifier during a passage mode and to a terminal terminated with a predetermined impedance during a blocking mode.

Abstract: A wireless communication apparatus that performs communication uses a communication method in which a transmission period and a reception period alternate with each other. The wireless communication apparatus includes a first antenna that transmits a radio signal during the transmission period and receives a radio signal during the reception period, a second antenna that receives the radio signal transmitted from the first antenna during the transmission period and receives a radio signal during the reception period, a first determining unit that determines a failure of the first antenna based on a ratio of a transmission power to a returning power for the radio signal transmitted from the first antenna, and a second determining unit that determines a failure of the second antenna based on a reception power of a radio signal received by the second antenna during the transmission period and a determination result of the first determining unit.

Abstract: A radio communication apparatus performing time division duplex alternately switching a transmission period and a reception period by time dividing an identical frequency, includes the steps of: detecting a transmission signal to be transmitted to the antenna so as to perform radio transmission from an antenna commonly used for transmission and reception; and calculating a deviation time between the detection timing of the detected transmission signal and a preset reference timing, and for controlling switchover timing between the transmission period and the reception period based on the deviation time.

Abstract: There is provided a transmitter receiver apparatus in which a directional coupler and single pole double throw (SPDT) switches are includes on the reception side. In the directional coupler, a reception signal is inputted and split into two signals having phases different from each other by 90° and the two split signals are outputted to SPDTs. Each of the SPDTs outputs each of the split signals to an output terminal connected to an amplifier during a passage mode and to a terminal terminated with a predetermined impedance during a blocking mode.