1. A method of packet detection and bandwidth classification, comprising: calculating a first averaged auto-correlation function for a first channel, wherein calculating the first averaged auto-correlation function comprises generating a first unaveraged auto-correlation function for the first channel in accordance with a predefined delay and taking a moving average of the first unaveraged auto-correlation function; calculating a second averaged auto-correlation function for a second channel, wherein calculating the second averaged auto-correlation function comprises generating a second unaveraged auto-correlation function for the second channel in accordance with the predefined delay and taking a moving average of the second unaveraged auto-correlation function; calculating a dot product of the first averaged auto-correlation function and the second averaged auto-correlation function; and detecting a packet, the detecting comprising classifying a bandwidth of the packet based at least in part on the dot product.