Experimental switched-diversity system for v.h.f. a.m. mobile radio

Switched diversity can provide a useful alternative to the well known combining methods in conditions where the noise on the various diversity branches is partially correlated. Because of its inherent simplicity it is attractive for mobile-radio use, and an experimental system has been constructed in the form of an `add-on¿ unit for a standard mobile receiver. Field trials have shown that the system can increase the reliability of communication, provided certain criteria are met, and have established other parameters of interest, such as the switching rate to be expected in practice. A practical system which prevents the receiver from remaining permanently connected to the poorer aerial during long fades is suggested.