| 摘要 |
PURPOSE:To prevent the degradation of the amplification quantity of a high frequency amplifier and the transmission of unnecessary high frequency signals due to cross modulation by switching the connection to a filter part in the cycle of a high frequency signal transmission time from a receiving antenna to a transmitting antenna to lead only the signal having a frequency corresponding to an input signal to the high frequency amplifier. CONSTITUTION:If the first high frequency input signal f1IN is received by a receiving antenna 1 when an input point 4a and an output point 4b are connected, a BPF5 permits only the input signal f1IN to pass through, and it is transmitted as the first high frequency output signal f1OUT from a transmitting antenna 3 after a high frequency signal transmission time tau(mus). A switch means 4 performs the switching operation to connect the point 4a to an output point 4c when the time tau(mus) elapses after the input signal f1IN is received, and as the result, an isolation high frequency signal F1 is stopped by a BPF6 and is not transmitted to a directional coupler 7. By the switching operation at intervals of the time tau(mus), the input signal f1IN is transmitted as the output signal f1OUT from the transmitting antenna 3 at intervals of the time tau(mus) without influences of the isolation high frequency signal F1. |
