RF filter architecture supporting simultaneous filtered reception of A and B bands of the cellular radio frequency spectrum

摘要

An RF filter for a cellular radio receiver whose architecture includes a combination of signal circulators and bandpass filters which operate to selectively notch out sub-bands of the two cellular bands of the cellular radio transmission spectrum so that the sub-bands of both cellular bands can be separately directed to a radio capable of receiving either or both the A or B-band signals. In its preferred form, the architecture of the filter includes two circulators, three bandpass filters having mutually different bandpass characteristics, covering selected portions of the A and B band and a diplexor.