| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce the scale and power consumption of a PLL synthesizer circuit by switching a voltage controlled oscillation part and a filter part forming a PLL to those which form another PLL and sharing a phase comparator and a reference oscillator by plural PLL loops. SOLUTION: A voltage controlled oscillation part 4 and a filter part 7 forming a transmitter PLL 1 are witched to a voltage controlled oscillation part 16 and a filter part 14 forming a base station field monitoring receiver loop 19, and a phase comparator 2 and a reference oscillator 8 are shared by both loops 1 and 19. When a transmitter 13 is working, the switch parts 6 and 12 are switched toward the loop 1 by the control signal sent from a control part 22. A switch part 32 outputs the control signals to turn on a power supply 24 of the part 4 and to turn off a power supply 25 of the part 16 respectively to operate the part 4 and also to stop the operation of the part 16.</p> |
