A digital front-end for a wireless communication system incorporates gain
control, signal detection, frame synchronization and carrier frequency
offset (CFO) estimation and correction features configured for use with
multiple receive antennas. The digital front-end may be applied to a
wireless communication system in which transmitted signals carry a
repeated signal pattern, such as orthogonal frequency division
multiplexing (OFDM) systems. An example of a repeated signal pattern is
the preamble of a signal transmitted according to the IEEE 802.11a
wireless local area network (WLAN) standard. The signal detection, frame
synchronization, and CFO estimation techniques make use of signals
received from multiple antenna paths to provide enhanced performance. The
gain control feature may be configured to adjust the gain in steps. The
frame synchronization technique may operate as a function of gain
control, handling the input signal differently before and after gain
adjustment.