Receiver with duty cycled listening

An apparatus for receiving a packet on one of a plurality of channels on a wireless network, wherein the packet includes a preamble field where a preamble is located, wherein the preamble is made up of a plurality of identical patterns, the apparatus comprising:

• an antenna to receive a signal containing the packet;
• an RF circuit to process the signal and create one or more received fragments from each of the plurality of channels;
• and
• a preamble detector comprising a plurality of correlators to detect a preamble based on at least one pattern in at least one received fragment on any of the plurality of channels, wherein the one or more received fragments received from each individual channel is at least one pattern in duration, and is spaced from a subsequent received fragment on that channel by an idle time, wherein the at least one received fragment is stored in the preamble detector as correlator content and each of the plurality of correlators is configured to operate on one of the plurality of channels to detect the at least one pattern either while a received fragment is being received, or during the idle time by cyclically shifting correlation coefficients relative to the correlator content.

An apparatus for receiving a packet on a wireless network, wherein the packet includes a preamble field where a preamble is located, wherein the preamble is made up of a plurality of identical patterns, the apparatus comprising:

• a first antenna to receive a first signal containing the packet;
• a second antenna to receive a second signal containing the packet;
• an antenna switch to select the first signal or the second signal from the first antenna and the second antenna by toggling the antenna switch during an idle time;
• an RF circuit to process the first signal and the second signal and create a first set of one or more received fragments when processing the first signal and create a second set of one or more received fragments when processing the second signal;
• and
• a preamble detector to detect a preamble based on at least one pattern in either the first set or the second set, wherein each received fragment from the first set is at least one pattern in duration, and successive received fragments are spaced by the idle time equal to a duration of an integral number of identical patterns and each received fragment from the second set is at least one pattern in duration, and successive received fragments are spaced by the idle time equal to the duration of an integral number of identical patterns.