Patent ID: 7145967

Claim:
A signal frequency splitter to derive n intermediate-frequency signals from a radio frequency signal, the signal frequency splitter comprising: a frequency synthesizer, to synthesize a local carrier signal F b1 according to a system frequency signal F g ; n−1 first mixers M 12 to M 1n coupled to the frequency synthesizer to mix frequencies of the local carrier signal F b1 and n−1 differential frequency signals F d2 to F dn , so as to obtain n−1 local carrier signals F b2 to F bn ; n second mixers M 21 , M 22 to M 2n coupled to the first mixers and the frequency synthesizer to mix frequencies of the radio frequency signal and the local carrier signals F b1 , F b2 to F bn to obtain n intermediate-frequency frequency-mixed signals F m1 to F mn ; and n filters coupled to the second mixers to filter the n intermediate-frequency frequency-mixed signals F m1 to F mn to obtain n intermediate-frequency signals; wherein n is a positive integer equal to or larger than 2.