Techniques are disclosed for measuring crosstalk between at least two communication channels of a communication system. A receiver of the system receives a signal over a given one of the communication channels from a transmitter of the system. The receiver correlates the received signal with a sequence of time-domain signals associated with another of the communication channels, and generates a measure of crosstalk between the given communication channel and the other communication channel based on the correlation between the received signal and the sequence of time-domain signals. The sequence of time-domain signals may be selected from a designated set of M-sequences.