Echo Metrics and Cancellation › Echo Delay

Echo Delay

Delay is the other key dimension of echo cancellation. As the ECAN examines the signal returning from the tail circuit, looking for a pattern that matches the signal sent into the tail circuit, it applies a convergence time algorithm to find the echo portion. Basically, this means that ECANs obey a time window that limits their operation. They look for the signal going into the tail circuit to be repeated in the signal coming back within a specific time, like 12 ms. Typical values are from 8 to 64 ms.