| 摘要 |
PURPOSE:To obtain the transmitter-receiver not generating an unlock alarm in a phase synchronization loop (PLL) synthesizer which is used as a local oscillation signal source for transmission and reception even when an out of phase synchronism of the frequency changeover transition period occurs in the TDMA communication system transmitter-receiver. CONSTITUTION:A transmission/reception part 10 includes a PLL synthesizer 5 supplying a local oscillation signal S13 with the frequency responding to a control signal S16a from a control part 6 to a transmission part 3 and a reception part 4. When an unlock of the phase synchronization occurs in the PLL synthesizer 5, an unlock alarm is displayed on an LCD display part 7 by control signals S16b and S19 from the synthesizer 5 and the control part 6. During the period of the unlock occurred on a frequency switch over transition period caused accompanying the frequency changeover of a transmission signal S11 and a reception signal S12, the PLL synthesizer 5 prohibits the generation of the unlock alarm. |
