Method and system for tracking timing drift in multiple frequency hypothesis testing
View Patent ↗A mobile device receives a signal comprising a PSS and performs multiple frequency hypothesis testing (MFHT) on the received signal. The mobile device starts MFHT by applying different initial frequency offsets in corresponding MFH branches. Timing drift in MFHT is compensated based on corresponding initial frequency offsets. In this regard, a PSS correlation process is performed on the received signal in each MFH branch. Resulting PSS correlation data is buffered and processed in corresponding PSS timing hypothesis buffers. The timing position of samples is updated in the PSS timing hypothesis buffers based on corresponding initial frequency offsets. Energy associated with the PSS transmissions may be accumulated utilizing corresponding PSS correlation data at updated sampling positions. The received PSS is detected based on a maximum accumulated energy associated with the PSS transmissions. Information that comes from the detected PSS is utilized by the mobile device to camp on a corresponding cell.
1. A method for communication, the method comprising:
in a mobile communication device:
receiving a signal comprising a primary synchronization sequence (PSS) transmitted from a base station;
performing multiple frequency hypothesis testing (MFHT) on said received signal utilizing multiple frequency hypothesis (MFH) branches; and
compensating for timing drift in said MFH branches based on initial frequency offsets applied to said corresponding MFH branches during said MFHT, including updating timing positions of data processed in said MFH branches based on said initial frequency offsets applied to said corresponding MFH branches.
2. The method according to claim 1 , comprising:
performing a PSS correlation process in each of said MFH branches on said received signal.
3. The method according to claim 2 , comprising buffering corresponding PSS correlation data in said each of said MFH branches.
4. The method according to claim 3 , comprising updating, based on said initial frequency offsets associated with said corresponding MFH branches, timing positions at which corresponding magnitudes of said buffered PSS correlation data are accumulated.
5. The method according to claim 4 , comprising determining rates for said updating based on said initial frequency offsets applied to said corresponding MFH branches.
6. The method according to claim 3 , comprising updating a timing position for said corresponding buffered PSS correlation data based on a sign of each of said initial frequency offsets applied to said corresponding MFH branches.
7. The method according to claim 6 , comprising updating said timing position of each of said corresponding buffered PSS correlation data to advance timing if said sign of each of said initial frequency offsets applied to said corresponding MFH branches are negative.
8. The method according to claim 6 , comprising updating said timing position of each of said corresponding buffered PSS correlation data to retard timing if said sign of each of said initial frequency offsets applied to said corresponding MFH branches are positive.
9. The method according to claim 6 , comprising accumulating energy associated with said received PSS utilizing said corresponding buffered PSS correlation data at said updated timing positions.
10. The method according to claim 9 , comprising detecting said received PSS based on said accumulated energy associated with said received PSS.
11. A system for communication, the system comprising:
one or more processors and/or circuits for use in a mobile communication device, said one or more processor and/or circuits being configured to:
receive a signal comprising a primary synchronization sequence (PSS) transmitted from a base station;
perform multiple frequency hypothesis testing (MFHT) on said received signal utilizing multiple frequency hypothesis (MFH) branches; and
compensate for timing drift in said MFH branches based on initial frequency offsets applied to said corresponding MFH branches during said MFHT, wherein said timing drift is compensated by updating timing positions of data processed in said MFH branches based on said initial frequency offsets applied to said corresponding MFH branches.
12. The system according to claim 11 , wherein said one or more processors and/or circuits are configured to perform a PSS correlation process in each of said MFH branches on said received signal.
13. The system according to claim 12 , wherein said one or more processors and/or circuits are configured to buffer corresponding PSS correlation data in said each of said MFH branches.
14. The system according to claim 13 , wherein said one or more processors and/or circuits are configured to update, based on said initial frequency offsets associated with said corresponding MFH branches, timing positions at which corresponding magnitudes of said buffered PSS correlation data are accumulated.
15. The system according to claim 14 , wherein said one or more processors and/or circuits are configured to determine rates for said updating based on said initial frequency offsets applied to said corresponding MFH branches.
16. The system according to claim 13 , wherein said one or more processors and/or circuits are configured to update a timing position for said corresponding buffered PSS correlation data based on a sign of each of said initial frequency offsets applied to said corresponding MFH branches.
17. The system according to claim 16 , wherein said one or more processors and/or circuits are configured to update said timing position of each of said corresponding buffered PSS correlation data to advance timing if said signs of said initial frequency offsets placed in said corresponding MFH branches are negative.
18. The system according to claim 16 , wherein said one or more processors and/or circuits are configured to update said timing position of each of said corresponding buffered PSS correlation data to retard timing if said sign of each of said initial frequency offsets applied to said corresponding MFH branches are positive.
19. The system according to claim 16 , wherein said one or more processors and/or circuits are configured to accumulate energy associated with said received PSS utilizing said corresponding buffered PSS correlation data at said updated timing positions.
20. The system according to claim 19 , wherein said one or more processors and/or circuits are configured to detect said received PSS based on said accumulated energy associated with said received PSS.