Method and apparatus for synchronization

1. An apparatus, comprising:

a baseband processing circuit configured to

encode a reference signal based on a specific one-dimensional sequence to generate a digital stream,

wherein the specific sequence has non-zero values at P selected positions, a number of coincidences of non-zero value positions between the specific sequence and each shifted copy of the specific sequence is at most a preset number, and

a total length L of the specific sequence is equal to or greater than P×(P−1)+1, wherein (P−1)=R N , R is a prime number, and N, P and L are positive integers; and

a transmitting circuit configured to transmit, via wireless signals, the digital stream that is generated based on the encoded reference signal.

2. The apparatus of claim 1 , wherein the baseband processing circuit is configured to encode one or more reference signals for synchronization and/or device identification based on the specific sequence.

3. The apparatus of claim 1 , wherein the baseband processing circuit is configured to encode the reference signal in at least one of a time domain, a frequency domain, or a time-frequency domain based on the specific sequence.

4. The apparatus of claim 1 , wherein the baseband processing circuit is configured to encode the reference signal based on the specific sequence with the non-zero values being one of constant, phase modulated, and amplitude modulated.

5. The apparatus of claim 1 , wherein the baseband processing circuit is configured to encode the reference signal in a frequency domain based on the specific sequence with the non-zero values being phase modulated to minimize a peak to average power ratio in a time domain.

6. The apparatus of claim 5 , wherein the baseband processing circuit is configured to encode the reference signal in the frequency domain based on the specific sequence with the non-zero values being phase modulated according to a binary phase-shift keying (BPSK).

7. The apparatus of claim 1 , further comprising:

a sequence providing circuit configured to provide the specific sequence to the baseband processing circuit.

8. The apparatus of claim 7 , wherein:

the sequence providing circuit comprises a memory configured to store the specific sequence.

9. The apparatus of claim 7 , wherein:

the sequence providing circuit comprises a sequence generator circuit configured to generate the specific sequence.

10. The apparatus of claim 7 , wherein

the sequence providing circuit comprises an interface circuit configured to receive the specific sequence from an external source that is out of the apparatus.

11. The apparatus of claim 1 , wherein the preset number is one.

12. The apparatus of claim 1 , wherein the number of coincidences of non-zero value positions is one.

13. A method for communication, comprising:

receiving a specific one-dimensional sequence having non-zero values at selected positions,

a number of coincidences of non-zero value positions between the specific sequence and

each shifted copy of the specific sequence being at most a preset number, and

a total length L of the specific sequence being equal to or greater than P×(P−1)+1, wherein (P−1)=R N , R is a prime number, and N, P, and L are positive;

encoding a reference signal based on the specific sequence to generate a digital stream; and

transmitting, via wireless signals, the digital stream that is generated based on the encoded reference signal.

14. The method of claim 13 , wherein encoding the reference signal based on the specific sequence to generate the digital stream further comprises:

encoding one or more reference signals for synchronization and/or device identification based on the specific sequence.

15. The method of claim 13 , wherein encoding the reference signal based on the specific sequence to generate the digital stream further comprises:

encoding the reference signal in at least one of a time domain, a frequency domain, or a time-frequency domain based on the specific sequence.

16. The method of claim 13 , wherein encoding the reference signal based on the specific sequence to generate the digital stream further comprises:

encoding the reference signal based on the specific sequence with the non-zero values being one of constant, phase modulated, and amplitude modulated.

17. The method of claim 13 , wherein encoding the reference signal based on the specific sequence to generate the digital stream further comprises:

encoding the reference signal in a frequency domain based on the specific sequence with the non-zero values being phase modulated to minimize a peak to average power ratio in a time domain.

18. The method of claim 17 , wherein the non-zero values are phase modulated according to a binary phase-shift keying (BPSK).

19. The method of claim 13 , wherein receiving the specific sequence having the non-zero values at the selected positions comprises:

storing the specific sequence in a memory; and

accessing the memory to receive the specific sequence.

20. The method of claim 13 , wherein receiving the specific sequence having the non-zero values at the selected positions comprises:

generating the specific sequence by a sequence generator circuit; and

receiving the specific sequence from the sequence generator circuit.

21. The method of claim 20 , wherein generating the specific sequence by the sequence generator circuit further comprises at least one of:

searching the specific sequence in a search space; and

constructing the specific sequence theoretically.

22. The method of claim 13 , wherein receiving the specific sequence having the non-zero values at the selected positions comprises:

receiving the specific sequence from an external source.

23. The method of claim 13 , wherein the preset number is one.

24. The method of claim 13 , wherein the number of coincidences of non-zero value positions is one.