Power saving diversity receiver

DETAILED DESCRIPTION It is therefore an object of the present invention to provide a power saving diversity receiver in which power supply to each diversity branch is cut off when it is out of circuit.
According to the present invention, the diversity receiver includes first and second diversity branches for respectively receiving a transmitted radio-frequency signal, the diversity branches respectively having first and second high-frequency amplifiers for amplifying the received signal to produce first and second diversity branch output signals.
A diversity decision circuit is coupled to the diversity branches for generating a switching control signal identifying one of the outputs of the first and second diversity branches having a higher field intensity value.
A power switching circuit is provided for coupling a voltage source to one of the high-frequency amplifiers in response to the switching control signal so that one of the first and second diversity branches is exclusively rendered active.
Preferably, the outputs of the diversity branches are coupled by respective strip lines to the diversity decision circuit to prevent mutual interference which might occur between the diversity branches.
The diversity decision circuit preferably includes a field intensity detector coupled to the outputs of first and second diversity branches to produce an intensity signal.
First and second sampling circuits are provided.
The first sampling circuit samples the intensity signal at periodic intervals and the second sampling circuit causes the power switching circuit to deactivate the active diversity branch and activate the inactive diversity branch when the intensity signal is sampled by the first sampling circuit and then samples the intensity signal.
The intensity signal sampled by the first and second sampling circuits are compared with each other to derive the switching control signal.