Steps one and three W-CDMA and multi-mode searching

In a system comprising a first pilot sequence transmitted during a portion of a slot, a second pilot sequence transmitted during a portion of each slot for a plurality of slots comprising a frame, and a third pilot transmitted continuously, a method of searching comprising:

• detecting the first pilot sequence in a first search engine and identifying slot timing therefrom;
• detecting the second pilot sequence in a second search engine, based on the identified slot timing, and identifying frame timing and base station group information therefrom;
• and
• detecting the third pilot sequence in the first search engine, based on the identified frame timing and base station group information.

A method of searching a pilot sequence transmitted during a portion of a slot, comprising:

• programming a plurality of sequence buffers with a plurality of sub-sequences of the pilot sequence;
• selecting one of the plurality of sequence buffers at a time for correlation with input samples;
• sequentially initiating coherent accumulation of correlation outputs for hypothesis offsets in a slot;
• and
• coherently accumulating the correlation outputs for each hypothesis offset using each of the plurality of sequence buffers to produce coherent accumulation outputs sequentially for the hypothesis offsets in the slot.

A searcher, operable with a first system comprising a plurality of base stations, each base station transmitting a signal divided by frames, the frames comprising a plurality of slots, the signal having:

• a first pilot sequence transmitted during a portion of each slot;
• a second pilot sequence, the second pilot sequence being a concatenation of a subset of sequences drawn from a larger set of sequences, the subset identifying the base station group of the transmitting base station, each of the subset of sequences transmitted during the portion of a slot coincident with the transmission of the first pilot sequence;
• and
• a third pilot sequence, continuously transmitted periodically with the frame, the third pilot sequence identifying the transmitting base station and used for communication therewith, the searcher comprising:
• a first search engine for detecting the first pilot sequence, deriving slot timing therefrom, and for detecting the third pilot sequence using derived frame timing and base station group information;
• and
• a second search engine for detecting the second pilot sequence and deriving frame timing and base station group information therefrom, the detection of the second pilot sequence using slot timing derived in the first search engine, and providing the derived frame timing and base station group information thereto.

A searcher, operable with a pilot sequence, transmitted during a portion of a slot, comprising:

• a time-shared correlator for correlating input samples with a plurality of sequences, each of the plurality of sequences correlated during a time slice;
• a sequence generator for generating the plurality of sequences, each of which are sub-sequences of the pilot sequence;
• and
• a coherent accumulator for accumulating the correlator output for a series of sequential offset hypotheses of the pilot sequence within a slot, the coherent accumulation for an offset hypothesis beginning during -each time slice, and the coherent accumulation for an offset hypothesis completing during each time slice subsequent to a coherent accumulation interval, each coherent accumulation result completing in sequential order of offset.

A searcher operable with a first pilot sequence transmitted during a portion of a slot and operable with a second pilot sequence transmitted continuously, comprising:

• a time-shared correlator for correlating input samples with a plurality of sequences, each of the plurality of sequences correlated during one of a plurality of time slices;
• a sequence generator configurable for generating the plurality of sequences, in a first mode each of which are sub-sequences of the first pilot sequence, and in a second mode each of which are a plurality of independent sequences, offsets within the second pilot sequence, or a combination thereof;
• and
• a coherent accumulator configurable for accumulating the correlator output:
• in the first mode for a series of sequential offset hypotheses of the pilot sequence within a slot, the coherent accumulation for an offset hypothesis beginning during each time slice, and the coherent accumulation for an offset hypothesis completing during each time slice subsequent to a coherent accumulation interval, each coherent accumulation result completing in sequential order of offset;
• and
• in the second mode for the plurality of sequential hypotheses corresponding to the plurality of time slices.

A subscriber unit including a searcher, operable with a pilot sequence, transmitted during a portion of a slot, comprising:

• a time-shared correlator for correlating input samples with a plurality of sequences, each of the plurality of sequences correlated during a time slice;
• a sequence generator for generating the plurality of sequences, each of which are sub-sequences of the pilot sequence;
• and
• a coherent accumulator for accumulating the correlator output for a series of sequential offset hypotheses of the pilot sequence within a slot, the coherent accumulation for an offset hypothesis beginning during each time slice, and the coherent accumulation for an offset hypothesis completing during each time slice subsequent to a coherent accumulation interval, each coherent accumulation result completing in sequential order of offset.

A W-CDMA system including a searcher, operable with a pilot sequence, transmitted during a portion of a slot, comprising:

• a time-shared correlator for correlating input samples with a plurality of sequences, each of the plurality of sequences correlated during a time slice;
• a sequence generator for generating the plurality of sequences, each of which are sub-sequences of the pilot sequence;
• and
• a coherent accumulator for accumulating the correlator output for a series of sequential offset hypotheses of the pilot sequence within a slot, the coherent accumulation for an offset hypothesis beginning during each time slice, and the coherent accumulation for an offset hypothesis completing during each time slice subsequent to a coherent accumulation interval, each coherent accumulation result completing in sequential order of offset.