Patent 7995459 was granted and assigned to Entropic Communications on August, 2011 by the United States Patent and Trademark Office.
In an orthogonal frequency division multiplex (OFDM) communication network, a node transmits an echo profile probe to other nodes in the network. The echo profile probe is a message that allows characterization of the unique echo profile through the communication channel between each node pair. The echo profile is used to calculate the cyclic prefix length needed for optimum communication from one node to the other.