Patent ID: 8804672

Claim:
A receiver-implemented method for detecting a preamble in a data signal transmitted from a transmitter and received at the receiver after a propagation delay, the method comprising: (a) generating a plurality of partial-profile values based on a first set of one or more chunks of the data signal, wherein: each chunk comprises multiple chips of the data signal; each partial-profile value corresponds to a different combination of (i) a possible preamble of a set of different possible preambles and (ii) a possible propagation delay of a set of different possible propagation delays; and the plurality of partial-profile values corresponds to a set of the different combinations; (b) selecting a subset of the set of the different combinations as two or more candidates based on the partial-profile values, wherein: each candidate corresponds to a different combination of a possible preamble and a possible propagation delay; and two or more of the plurality of partial-profile values are generated in step (a) before selecting any of the two or more candidates in step (b); (c) generating two or more full-profile values based on a second set of chunks of the data signal, wherein each full-profile value corresponds to a different selected candidate; and (d) detecting the preamble based on the two or more full-profile values.