- WIDE BAND ZERO IF QUADRATURE DEMODULATOR USING A INTERMEDIATE FREQUENCY AND A SINGLE LOCAL OSCILLATOR

摘要

The low power zero-IF select call receiver comprises a local oscillator generating an injection signal for the first mixer 104 and a pair of quadrature phase related injection signals 122, 124 for the pair of second mixers 112, 114 ( 106). The first mixer converts the received carrier signal 102 into an intermediate signal 108. The digital phase shifter / divider 116 in combination with the local oscillator 106 is a pair of quadrature phase related injection at the frequency of the intermediate signal 108 that is equal to the frequency of the local oscillator 106 divided by an integer greater than one. Generate signals 122 and 124. A pair of second mixers 112 and 114 in combination with the digital phase shifter / divider 116 converts the in-phase and quadrature phase components 122 and 124 of the intermediate signal 108 to the in-phase and quadrature phase bases, respectively. Convert to band signals 126 and 128.