Diversity signal synthesizing control system

Abstract

Abstract PURPOSE:To stabilize the operation and to enable to monitoring of operation, by coupling a pilot signal to an input of a variable attenuator, detecting a pilot level attenuated at the variable attenuator and controlling the attenuator with feedback operation. CONSTITUTION:A diversity signal received at an antenna is demodulated at a receiver and after being attenuated at variable attenuators i05 (where; i=1-n), the signals are synthesized at 11 and outputted. An out-band noise passes through a BPF, it is converted into a voltage at a control voltage generator i04 and inputted to a differential amplifier i06 and a best path detector 13. The detector 13 detects a voltage with the best S/N, an amplifier i06 picks up the difference between the voltage and a voltage from the generator i04 and inputs it to a comparator i10. An output of a pilot PL oscillator 14 is inputted to each attenuator, the attenuated signal is picked up at the BPF, a voltage detected at a PL level detector i08 is inputted to the highest level detector 15 and a differential amplifier i09. A comparison output between the difference of voltages at each PL and the highest PL picked up at the amplifier i09 and the output of the amplifier i06 controls the attenuators and the result is monitored at i11.

Inventors

• 👤 Atsushi Muromoto

Bibliographic Details