Chunk-based double-dwell preamble detection

An apparatus for detecting a preamble in a data signal transmitted from a transmitter and received at the receiver after a propagation delay, the apparatus comprising:

• a partial-profile value generator configured to generate 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;
• a candidate selector configured to select 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 before selecting any of the two or more candidates;
• a full-profile value generator configured to generate 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
• a preamble detector configured to detect the preamble based on the two or more full-profile values.