Phase difference measuring appts. for phase modulated equipment - employs frequency division and multiple comparator modules to extend system range and accuracy

摘要

The method of determining the phase separation between pulses in phase modulated equipment employs frequency division (7,8) and multiple phase comparators (9 to 12) to extend the measurement system range and accuracy. An even number of successive pulses are monitored by an equivalent number of comparators (9 to 12) and compared with fixed reference pulses. The comparator modules (9 to 12) are of basic digital design employing cating or flip-flop circuits with suitable low-pass filters for minimising HF noise components and their respective outputs are summed in an additive module (13). USE/ADVANTAGE - All types of standard digital phase comparator are suitable system sensitivity is increased in direct proportion to number of comparator modules in use. Four modules are recommended to compromise with cost. Spurious signal components are suppressed steep slope filters unnecessary allowing wider frequency boundaries response linearity and speed improved for fast moving changes.