A processing module for a receiver device configured to provide for processing of a frame received by the receiver device from a transmitter device, the at least one frame comprising a plurality of repeating predetermined synchronization symbols for providing synchronization between the processing module and the transmitter device and one or more start-of-frame symbols defining the end of the synchronization symbols, the processing module configured to: perform cross correlation to obtain a cross-correlation function on i) at least a part of the received frame; with ii) a predetermined modulation sequence used to modulate the one or more start-of-frame symbols and not the synchronization symbols; and determine the location of the start-of-frame symbols based on an increase, above a threshold increase, in the cross-correlation function from a negative cross-correlation with the synchronization symbols to a greater cross-correlation with the part of the received frame containing the start-of-frame symbols.