Wireless communications system with secondary synchronization code based on values in primary synchronization code
View Patent ↗A wireless communication system. The system comprises transmitter circuitry (BST 1 ), the transmitter circuitry comprising encoder circuitry ( 50 ) for transmitting a plurality of frames (FR). Each of the plurality of frames comprises a primary synchronization code (PCS) and a second synchronization code (SSC). The encoder circuitry comprises of circuitry ( 501 ) for providing the primary synchronization code in response to a first sequence ( 32 ). The encoder circuitry further comprises circuitry ( 502 ) for providing the secondary synchronization code in response to a second sequence ( 54 ) and a third sequence ( 56 ). The second sequence is selected from a plurality of sequences. Each of the plurality of sequences is orthogonal with respect to all other sequences. The third sequence is a subset of bits from the first sequence.
1. A method of decoding a synchronization code, comprising the steps of:
identifying in an apparatus a primary synchronization code comprising a first code sequence;
identifying in the apparatus a secondary synchronization code comprising a second code sequence combined with a third code sequence, the third code sequence being different from the first code sequence,
wherein the second code sequence is from a plurality of sequences;
wherein each of the plurality of sequences is orthogonal with respect to all other sequences in the plurality of sequences; and
wherein the third code sequence comprises a sequence of bits of the first code sequence, and wherein the sequence of bits of the first code sequence is repeated a plurality of times in the third sequence.
2. The method of claim 1 , wherein the second code sequence comprises 256 bits, and
wherein the third code sequence comprises 32 repeated instances of the a subset of bits from the first code sequence.
3. The method of claim 2 , wherein the second code sequence comprises a plurality of code words, and wherein each code word of the plurality of code words is selected from a plurality of Hadamard sequences.
4. The method of claim 1 , wherein each of the second and third code sequences comprise 256 bits, and wherein the subset of bits from the first code sequence comprises a fourth code sequence of bits and a complement of the fourth code sequence of bits.
5. The method of claim 4 , wherein the second code sequence comprises a plurality of code words, and wherein each code word of the plurality of code words is selected from a plurality of Hadamard sequences.
6. The method of claim 5 , wherein the plurality of Hadamard sequences are selected from a set of 256 Walsh sequences, wherein the 256 Walsh sequences have a defined order, and wherein the plurality of Hadamard sequences comprise seventeen Hadamard sequences selected as every eighth sequence in the defined order.