Method and apparatus for broadcast channel decoding
View Patent ↗A method and apparatus for decoding the LTE physical broadcast channel (PBCH). The transmissions are made by an evolved NodeB (eNB). At least one template symbol sequence representative of a potential transmission by the eNB over the PBCH is provided. A signal or signals transmitted over the PBCH by the eNB is received, the signal or signals indicative of a received symbol sequence. Correlation operations are performed for correlating the at least one template symbol sequence against the received symbol sequence. A representative symbol sequence, timing parameter, or both, is selected, based on the correlation operations. The representative symbol sequence is indicative of information transmitted by the eNB over the LTE PBCH. The timing parameter is indicative of timing of said information transmitted by the eNB.
1. A method for decoding transmissions over a physical broadcast channel (PBCH) by a user equipment (UE), said transmissions made by a base station, wherein the PBCH provides timing information and configuration information for supporting communication, the method comprising:
providing at least one template symbol sequence representative of a potential transmission by the base station over the PBCH;
receiving one or more signals transmitted over the PBCH by the base station, the one or more signals indicative of a received symbol sequence;
processing the one or more signals to extract the received symbol sequence;
performing correlation operations between the at least one template symbol sequence and the received symbol sequence; and
selecting a representative symbol sequence, timing parameter, or both, based on the correlation operations, said representative symbol sequence indicative of information transmitted by the base station over the PBCH,
wherein each of the correlation operations comprises multiplying one of the at least one template symbol sequences with the received symbol sequence for a plurality of different time shifts.
2. The method according to claim 1 , further comprising: providing information related to data potentially encoded into the potential transmission, wherein the at least one template symbol sequence is generated based at least in part on said provided information.
3. The method according to claim 2 , wherein said provided information is determined based on anticipated contents of a Master Information Block (MIB) transmitted by the base station and received by the UE.
4. The method according to claim 3 , further comprising constraining, by the base station, contents of the transmitted MIB, thereby improving predictability of said contents, improving correlation properties of the MIB, or both.
5. The method according to claim 2 , wherein said anticipated contents of the MIB are based on contents of a received SIB1 system information block.
6. The method according to claim 2 , wherein the provided information is stored information.
7. The method according to claim 2 , wherein the provided information is obtained by processing signals received from the base station.
8. The method according to claim 7 , wherein the provided information comprises one or more of: an RF bandwidth, data obtained from decoding SIB1, and reference symbols indicative of antenna configuration.
9. The method according to claim 1 , wherein the at least one template symbol sequence comprises two or more template symbol sequences, and wherein the correlation operations comprises correlating the two or more template symbol sequences against the received symbol sequence.
10. The method according to claim 1 , further comprising selecting a portion of the template symbol sequence, and wherein the correlation operation comprises correlating the selected portion of the template symbol sequence against at least a corresponding portion of the received symbol sequence, wherein the selected portion is a strict contiguous or non-contiguous subset of the template symbol sequence.
11. The method according to claim 1 , wherein the correlation operations are performed in support of an adaptive search for the representative symbol sequence, timing parameter, or both based on the at least one template symbol sequence, wherein the adaptive search comprises one or more of: a depth-first search, a breadth-first search, and a best-first search.
12. The method according to claim 1 , wherein the representative symbol sequence is selected as one of said at least one template symbol sequences which correlates most strongly with the received symbol sequence.
13. The method according to claim 1 , wherein said timing parameter provides an indication of timing in a wireless communication system between the UE and the base station, and wherein further decoding of received data is performed making use of said system timing.
14. A method for decoding transmissions over a physical broadcast channel (PBCH) by a user equipment (UE), said transmissions made by a base station, wherein the PBCH provides timing information and configuration information for supporting communication, the method comprising:
providing at least one template symbol sequence representative of a potential transmission by the base station over the PBCH;
receiving one or more signals transmitted over the PBCH by the base station, the one or more signals indicative of a received symbol sequence;
processing the one or more signals to extract the received symbol sequence;
performing correlation operations between the at least one template symbol sequence and the received symbol sequence; and
selecting a representative symbol sequence, timing parameter, or both, based on the correlation operations, said representative symbol sequence indicative of information transmitted by the base station over the PBCH,
wherein the correlation operations comprise a first round of correlation operations and a second round of correlation operations subsequent to the first round, wherein correlation operations during the first round are applied to smaller portions of the at least one template symbol sequence than correlation operations during the second round, and wherein fewer correlation operations are applied during the second round than during the first round, said fewer correlation operations selected based on an outcome of the first round.
15. A method for decoding transmissions over a physical broadcast channel (PBCH) by a user equipment (UE), said transmissions made by a base station, wherein the PBCH provides timing information and configuration information for supporting communication, the method comprising:
providing at least one template symbol sequence representative of a potential transmission by the base station over the PBCH;
receiving one or more signals transmitted over the PBCH by the base station, the one or more signals indicative of a received symbol sequence;
processing the one or more signals to extract the received symbol sequence;
performing correlation operations between the at least one template symbol sequence and the received symbol sequence; and
selecting a representative symbol sequence, timing parameter, or both, based on the correlation operations, said representative symbol sequence indicative of information transmitted by the base station over the PBCH,
wherein performing the correlation operations comprises applying a plurality of time shifts to at least one of the template symbol sequences, and wherein the timing parameter corresponds to one of said plurality of time shifts which results in a strongest element of a correlation function between one of said at least one of the template symbol sequences and the received symbol sequence.
16. A user equipment (UE) apparatus for decoding transmissions over a physical broadcast channel (PBCH), said transmissions made by a base station, wherein the PBCH provides timing information and configuration information for supporting communication, the apparatus comprising:
a template module configured to provide at least one template symbol sequence representative of a potential transmission by the base station over the PBCH;
a receiver module configured to receive one or more signals transmitted over the PBCH by the base station, the one or more signals indicative of a received symbol sequence, the receiver module further configured to process the one or more signals to extract the received symbol sequence;
a correlation module configured to perform correlation operations between the at least one template symbol sequence and the received symbol sequence; and
an evaluation module configured to select a representative symbol sequence, timing parameter, or both, based on the correlation operations, said representative symbol sequence indicative of information transmitted by the base station over the PBCH,
wherein the correlation module is configured to correlate the at least one template symbol sequence against the received symbol sequence using a plurality of different time shifts.
17. The apparatus according to claim 16 , wherein the template module is further configured to provide information related to data potentially encoded into the potential transmission, and to generate each of the at least one template symbol sequences based at least in part on said provided information.
18. The apparatus according to claim 17 , wherein the provided information is stored information.
19. The apparatus according to claim 17 , wherein the provided information is obtained by processing signals received from the base station.
20. The apparatus according to claim 19 , wherein the provided information comprises one or more of: an RF bandwidth, data obtained from decoding SIB1, and reference symbols indicative of antenna configuration.
21. The apparatus according to claim 16 , wherein the at least one template symbol sequence comprises two or more template symbol sequences, and wherein the correlation module is configured to correlate the two or more template symbol sequences against the received symbol sequence.
22. The apparatus according to claim 16 , wherein the correlation module is further configured to select a portion of the template symbol sequence, and wherein the correlation operation comprises correlating the selected portion of the template symbol sequence against at least a corresponding portion of the received symbol sequence, wherein the selected portion is a strict contiguous or non-contiguous subset of the template symbol sequence.
23. The apparatus according to claim 16 , wherein the correlation operations are performed in support of an adaptive search for the representative symbol sequence, timing parameter, or both based on the at least one template symbol sequence, wherein the adaptive search comprises one or more of: a depth-first search, a breadth-first search, and a best-first search.
24. The apparatus according to claim 16 , wherein the correlation module comprises a FFT/IFFT hardware accelerator block which is also used for one or more other signal processing operations of the apparatus.
25. A user equipment (UE) apparatus for decoding transmissions over a physical broadcast channel (PBCH), said transmissions made by a base station, wherein the PBCH provides timing information and configuration information for supporting communication, the apparatus comprising:
a template module configured to provide at least one template symbol sequence representative of a potential transmission by the base station over the PBCH;
a receiver module configured to receive one or more signals transmitted over the PBCH by the base station, the one or more signals indicative of a received symbol sequence, the receiver module further configured to process the one or more signals to extract the received symbol sequence;
a correlation module configured to perform correlation operations between the at least one template symbol sequence and the received symbol sequence; and
an evaluation module configured to select a representative symbol sequence, timing parameter, or both, based on the correlation operations, said representative symbol sequence indicative of information transmitted by the base station over the PBCH,
wherein the correlation module is configured to perform a first round of correlation operations and a second round of correlation operations subsequent to the first round, wherein correlation operations during the first round are applied to smaller portions of the at least one template symbol sequence than correlation operations during the second round, and wherein fewer correlation operations are applied during the second round than during the first round, said fewer correlation operations selected based on an outcome of the first round.
26. A computer program product comprising a non-transitory computer readable medium storing computer executable statements and instructions thereon that, when executed by a computer, perform operations for decoding transmissions over a physical broadcast channel (PBCH) by a user equipment (UE), said transmissions made by a base station, wherein the PBCH provides timing information and configuration information for supporting communication, the operations comprising:
providing at least one template symbol sequence representative of a potential transmission by the base station over the PBCH;
receiving one or more signals transmitted over the PBCH by the base station, the one or more signals indicative of a received symbol sequence;
processing the one or more signals to extract the received symbol sequence;
performing correlation operations between the at least one template symbol sequence and the received symbol sequence; and
selecting a representative symbol sequence, timing parameter, or both, based on the correlation operations, said representative symbol sequence indicative of information transmitted by the base station over the PBCH,
wherein each of the correlation operations comprises multiplying one of the at least one template symbol sequences with the received symbol sequence for a plurality of different time shifts.
27. A user equipment (UE) apparatus for decoding transmissions over a physical broadcast channel (PBCH), said transmissions made by a base station, wherein the PBCH provides timing information and configuration information for supporting communication, the apparatus comprising:
a template module configured to provide at least one template symbol sequence representative of a potential transmission by the base station over the PBCH;
a receiver module configured to receive one or more signals transmitted over the PBCH by the base station, the one or more signals indicative of a received symbol sequence, the receiver module further configured to process the one or more signals to extract the received symbol sequence;
a correlation module configured to perform correlation operations between the at least one template symbol sequence and the received symbol sequence; and
an evaluation module configured to select a representative symbol sequence, timing parameter, or both, based on the correlation operations, said representative symbol sequence indicative of information transmitted by the base station over the PBCH,
wherein the correlation module is configured to perform the correlation operations by applying a plurality of time shifts to at least one of the template symbol sequences, and wherein the timing parameter corresponds to one of said plurality of time shifts which results in a strongest element of a correlation function between one of said at least one of the template symbol sequences and the received symbol sequence.