Duplex diversity operation of vehicular mobile radio installation - comparing buffered radiotelephone reception quality signals for actuation of transistor-switched antenna selection relay

摘要

Two receiving antennas (A1, A2) are connected selectively by a diversity relay (HT1) actuated by a transistor (T1). Voltages (U1, U2) representing the quality of their received signals are applied through buffer operational amplifiers (OP2, OP4) to a discriminator (OP3). Whichever antenna provides better reception is selected for the greater part of the time, and the other is switched-in only for the duration required for refreshment of the corresp. memory capacitor (C3 or C5) to the actual quality value. USE/ADVANTAGE - Esp. on motor vehicle, interference arising from different directional effects of individual antennas is suppressed and multipath fading is minimised.