Synchronisation monitor for transmitter - has diode at circulator absorber output to switch off transmit oscillator when synchronisation fails

摘要

Thesynchronisation monitor, is used for transmitter with injection synchronised oscillator in broadband communication system. It has a diode connected to the output of the absorber to indicate the non-synchronised state and/or to switch off the free-running oscillator. Antenna couplers have filters tuned to the transmit frequency and decoupled from the transmit amplifier by a circulator such that mismatch at the amplifier side of the filter is suppressed by an absorber coupled to the circulator. The oscillator is switched off, preventing interference with neighbouring channels when synchronisation fails.