Ascertaining a signal power of an Orthogonal Frequency Division Multiplexing (OFDM) signal involves ascertaining a plurality of channel estimates from the OFDM signal. Compensating phase shift values for phase aligning the plurality of channel estimates are estimated and used to generate phase corrected channel estimates. The phase corrected channel estimates are coherently combined, thereby ascertaining the signal power of the OFDM signal. The compensating phase shift values may be based on a channel characteristic (e.g., delay spread) or may alternatively be hypothesized.