DIVERSITY RECEPTION SYSTEM

摘要

A method and apparatus for processing signals transmitted over multipath routes. The method involves receiving the signals through at least two antennas and adding the received signals and selecting one of a first and second mode for adding the received signals. The step of selecting one of a first and second mode comprising the step of selecting one of a first mode in which there is no phase shift in the signals from a first of the antennas and a second mode in which there is a phase shift of more than 90.degree. of the carrier frequency of the signals received from one of the antennas before the signals are added. The amplitude of the sum of the added signals is compared to a predetermined threshold and the second modes are selected when the amplitude is lower than the predetermined threshold value. The apparatus includes first and second antennas with means for adding the signals received by the antennas together to provide a sum signal with time delay means of at least 90.degree. of a cycle of the carrier wave of the signals. There is receiving means for processing the sum signal and indicating means for providing an indicating signal related to the strength of the sum signal. There is switch means responsive to the indicating means for selectively connecting the time delay into a path between the first antenna and the means for adding and connecting the first antenna directly to the means for adding.