发明名称 DYNAMIC REFERENCE FREQUENCY FOR FRACTIONAL-N PHASE-LOCKED LOOP
摘要 Within a receiver, the frequency of a comparison reference clock signal supplied to a fractional-N Phase-Locked Loop (PLL) is dynamically changed such that undesirable reciprocal mixing of reference spurs with known jammers (for example, transmit leakage) is minimized. As the transmit channel changes within a band, and as the transmit leakage frequency changes, a circuit changes the frequency of the comparison reference clock signal such that reference spurs generated by the PLL are moved in frequency so that they do not reciprocally mix with transmitter leakage in undesirable ways. In a second aspect, the PLL is operable either as an integer-N PLL or a fractional-N PLL. In low total receive power situations, the PLL operates as an integer-N PLL to reduce receiver susceptibility to fractional-N spurs. In a third aspect, jammer detect information is used to determine the comparison reference clock signal frequency.
申请公布号 US2009221235(A1) 申请公布日期 2009.09.03
申请号 US20090366441 申请日期 2009.02.05
申请人 QUALCOMM INCORPORATED 发明人 CICCARELLI STEVEN C.;BOSSU FREDERIC;APARIN VLADIMIR;WANG KEVIN H.
分类号 H03D3/24;H04B7/00;H04B17/00;H04M1/00 主分类号 H03D3/24
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