Patent ID: 8077659

Claim:
A method of estimating a current location of a receiver in a mobile multimedia multicast system comprising said receiver, at least three transmitters, and a wireless network, said method comprising: receiving digital signals comprising a mobile multimedia multicast system superframe comprising orthogonal frequency division multiplexing (OFDM) symbols; performing slot 3 processing of each medium access control (MAC) time unit of a data channel to identify a transmitter identity (TxID) of each transmitter; identifying corresponding geographical coordinates of each TxID; regenerating said digital signals for each of said transmitters using a local-area differentiator (LID) and a wide-area differentiator (WID) of said transmitters; dividing said digital signals received from said transmitters by the corresponding regenerated transmitted signal to obtain channel estimates between said receiver and the corresponding transmitters; detecting a first peak in said channel estimates to determine a distance between said receiver and said corresponding transmitters, wherein the detecting comprises: measuring a noise level at slot 5 of said MAC time unit; measuring a signal level of the remaining slots of said MAC time unit; obtaining a level of the signal-to-noise ratio (SNR) of said digital signals; and setting a threshold level to detect each peak in said channel estimates; calculating a time difference of arrival of said digital signals emitted from said transmitters; and estimating a current location of said receiver by determining said time difference of arrival associated with geographical coordinates of said receiver.