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 (BST1), 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 secondary synchronization code (SSC). The encoder circuitry comprises of circuitry (50 1 ) for providing the primary synchronization code in response to a first sequence (32). The encoder circuitry further comprises circuitry (50 2 ) 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 in the plurality of sequences. The third sequence comprises a subset of bits from the first sequence.
1. A code generator circuit for producing a synchronization code for a wireless communication device, comprising:
a circuit for providing a primary synchronization code in response to a first sequence; and
a circuit for providing a secondary synchronization code in response to a second sequence and a third sequence,
wherein the second sequence is one of a plurality of orthogonal sequences, and
wherein the third sequence includes a plurality of subsets of bits, each subset including a fourth sequence of bits from the first code sequence and a complement of a fifth sequence of bits from the first code sequence.
2. A code generator circuit as in claim 1 , wherein the first sequence comprises a hierarchical sequence.
3. A code generator circuit as in claim 1 , wherein the first sequence comprises a Golay sequence.
4. A code generator circuit as in claim 1 , wherein the second sequence comprises a plurality of code words, and wherein each of the plurality of code words is selected from a plurality of Hadamard sequences.
5. A code generator circuit as in claim 4 , wherein the second sequence consists of fifteen of the code words.
6. A code generator circuit as in claim 5 , wherein the plurality of Hadamard sequences is selected from a set of 256 Walsh sequences.
7. A code generator circuit as in claim 6 , wherein the 256 Walsh sequences have a defined order, and wherein the plurality of Hadamard sequences comprise sixteen Hadamard sequences selected as every sixteenth sequence in the defined order.
8. A code generator circuit as in claim 4 , wherein the second sequence consists of sixteen of the code words.
9. A code generator circuit as in claim 8 , wherein the plurality of Hadamard sequences is selected from a set of 256 Walsh sequences.
10. A code generator circuit as in of claim 6 , 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.
11. A code generator circuit as in claim 1 , wherein the circuit for providing the secondary synchronization code comprises: a circuit for performing an exclusive OR operation between the second sequence and the third sequence; and a circuit for providing the secondary synchronization code in response to the exclusive OR operation.
12. A code generator circuit as in claim 1 , wherein the primary synchronization code consists of 8-bit values A and B and complements of the values A and B; wherein the value A comprises a sequence A={1, 1, 1, 1, 1, 1, −1, −1}; wherein the value B comprises a sequence B={1, −1, 1, −1, 1, −1, −1, 1}; wherein a value C is defined as a sequence C={A, −B}; wherein the third sequence comprises a 256-bit sequence {C, C, C, −C, C, C, −C, −C, C, −C, C, −C, −C, −C, −C, −C}.
13. A code generator circuit as in claim 12 , wherein the circuit for providing the secondary synchronization code comprises: a circuit for performing an exclusive OR operation between the second sequence and the third sequence; and a circuit for providing the secondary synchronization code in response to the exclusive OR operation.
14. A code generator circuit as in claim 13 , wherein the second sequence comprises a plurality of code words, and wherein each of the plurality of code words is selected from a plurality of Hadamard sequences.
15. A code generator circuit as in claim 14 , 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 sixteen Hadamard sequences selected as every sixteenth sequence in the defined order.
16. A code generator circuit as in claim 1 , comprising a CDMA transmitter.
17. A code generator circuit as in claim 1 , comprising a CDMA receiver.
18. A code generator circuit as in claim 1 , wherein the circuit for providing the secondary synchronization code comprises a storage circuit for storing the secondary synchronization code.
19. A code generator circuit as in claim 18 , wherein the secondary synchronization code stored by the storage circuit is derived from an exclusive OR operation between the second sequence and the third sequence.