Patent ID: 7899639

Claim:
An echo measurement device (EMD), comprising a controller to: transmit a test signal in a communication path which is looped back at an end point identified as having an echo problem, wherein the test signal is transmitted at a remote location from the end point, and wherein the test signal comprises a limited burst signal of one or more frequencies operating outside a range of an operating frequency of an echo canceller deactivation signal transmitted in the communication path; record loopback signals; calculate a loopback delay of the test signal from the loopback signals; calculate a loopback delay associated with each of the one or more echo signals detected in the loopback signals; and determine a round trip delay at the end point for each of the one or more echo signals according to a difference between the loopback delay of the test signal and the loopback delay associated with each of the one or more echo signals.