A phase-locked 4-6 GHz local oscillator using microwave prescaler

A phase-locked broadband local oscillator using a divide-by-8 microwave prescaler is described. The measured phase noise characteristics of the prescaler, the reference source, and the phase-locked source are discussed. The threshold bit error rate curve of a 6-GHz 64-QAM microwave digital radio using this direct division source is given and compared with that of a source using a multiplier and mixer configuration.<>