Patent ID: 7577216

Claim:
A mode detector within a receiver, comprising: a correlation calculator that generates a correlation signal from an in-phase and quadrature (I/Q) stream; a multi-sliding integrator that generates a plurality of GI mode division signals by in part delaying the correlation signal with different delays; a plurality of peak value accumulators that generates a respective peak-value position and a respective peak-value for each of the GI mode division signals; and a decision unit that determines a GI mode and a FFT mode of the I/Q stream from the respective peak-value positions and the respective peak-values of the GI mode division signals; wherein the correlation calculator is coupled to the decision unit to generate the correlation signal dependent on the FFT mode as indicated by a FFT mode signal from the decision unit, and wherein the multi-sliding integrator operates without the FFT mode signal being directly fed-back to the multi-sliding integrator, and wherein the correlation calculator comprises: a decimation unit that generates a decimated I/Q stream by sampling the I/Q stream by 1/M; and a selector that selects one of the I/Q stream or the decimated I/Q depending on the FFT mode to generate a selected I/Q stream.