Signal receiving system

摘要

A signal receiving system includes a variable directivity antenna having its directivity varied in accordance with a control signal applied thereto. A control signal generator generating the control signal is provided in a receiving apparatus. The receiving apparatus includes also a modulator operating to ASK (amplitude-shift-keying) modulate a carrier with the control signal from the control signal generator into an ASK modulated signal. The ASK modulated signal is applied through a transmission line to the variable directivity antenna, and a controller associated with the variable directivity antenna demodulates the ASK modulated signal to recover the control signal for use in varying the directivity of the variable directivity antenna.