Patent ID: 7406139

Claim:
A method to identify a modulation format of a data frame received from a servicing base station by a wireless terminal in a cellular wireless communication system, the method comprises: receiving a first Radio Frequency (RF) burst of the data frame from the servicing base station, wherein the first RF burst carries a plurality of modulated symbols and a burst index; when the burst index of the first RF burst comes within a predetermined index value, extracting a training sequence from the first RF burst, wherein the training sequence includes modulated symbols; processing the training sequence assuming a first modulation format to produce a first channel energy; processing the training sequence assuming a second modulation format to produce a second channel energy; determining a greater channel energy from the first channel energy and the second channel energy; receiving a subsequent RF burst within the data frame from the servicing base station, wherein the subsequent RF burst carries a plurality of modulated symbols and a subsequent burst index; when the subsequent burst index comes within the predetermined index value, processing the training sequence assuming the first modulation format to produce a subsequent first channel energy; accumulating the subsequent first channel energy with the first channel energy to produce an accumulated first channel energy; processing the training sequence assuming the second modulation format to produce a subsequent second channel energy; accumulating the subsequent second channel energy with the second channel energy to produce an accumulated second channel energy; determining a greater accumulated channel energy from the first accumulated channel energy and the second accumulated channel energy; and identifying the modulation format of the data frame as corresponding to the greater accumulated channel energy.