Editing Continuous-wave radar (section)

====Interruption, FMICW====
While interrupted carrier systems are not considered to be CW systems, performance characteristics are sufficiently similar to group interrupted CW systems with pure CW radar because the pulse rate is high enough that range measurements cannot be done without frequency modulation (FM).

This technique turns the transmitter off for a period before receiver sampling begins. Receiver interference declines by about 8.7&nbsp;dB per time constant. Leakage reduction of 120&nbsp;dB requires 14 recover bandwidth time constants between when the transmitter is turned off and receiver sampling begins.

The interruption concept is widely used, especially in long-range radar applications where the receiver sensitivity is very important. It is commonly known as "frequency modulated interrupted continuous wave", or FMICW.