SSB transmissions in unlicensed spectrum
A method is implemented in a wireless transceiver device arranged to operate in a cellular wireless communication network and capable of operating in an unlicensed spectrum where listen-before-talk is employed. The method includes determining a first parameter, for the unlicensed operation, indicative on provision of synchronisation signal blocks, and determining quasi-co-location, QCL, relationship between one or more synchronisation signal and physical broadcast channel, SS/PBCH, blocks each having a first index, by determining a second index for the one or more SS/PBCH blocks by applying a modulo operation on the first index, respectively, based on the first parameter, where the QCL relationship is determined to occur if the second indices coincide. A computer program for implementing the method in a wireless transceiver and such a transceiver are also disclosed.
1. A method implemented in a wireless transceiver device arranged to operate in a cellular wireless communication network and capable of operating in a spectrum where listen-before-talk is employed, the method comprising
determining a first parameter indicative on provision of synchronisation signal blocks, the determining of the first parameter comprising receiving at least a part of the first parameter from a master information block (MIB) or physical broadcast channel (PBCH) payload, or a combination of the two; and
determining a quasi-co-location (QCL) relationship between two or more synchronisation signal and physical broadcast channel (SS/PBCH) blocks of a plurality of SS/PBCH blocks, each SS/PBCH block having a first index, the plurality of SS/PBCH blocks comprising at least a first SS/PBCH block and a second SS/PBCH block, the QCL relationship being determined to occur if at least a first result of a modulo operation of the first index of the first SS/PBCH block and the first parameter coincides with a second result of the modulo operation of the first index of the second SS/PBCH block and the first parameter.
2. The method of claim 1 , comprising determining a frame timing based on the first index associated with a detected SS/PBCH block.
3. The method of claim 1 , wherein the determining of the QCL relationship comprises:
determining one or more desired second indices from transmission history;
determining a second index for each one of two or more received SS/PBCH blocks as the first index modulo the first parameter; and
comparing the second indices associated with at least two of the two or more received SS/PBCH blocks.
4. The method of claim 1 , comprising determining a QCL shift indicator, and wherein the determining of the QCL relationship comprises:
determining one or more desired second indices from transmission history;
determining a second index for each one of two or more received SS/PBCH blocks as the first index modulo the first parameter minus the determined QCL shift when the second index becomes positive and as the first index modulo the first parameter minus the determined QCL shift plus the first parameter otherwise; and
comparing the second indices associated with at least two of the two or more received SS/PBCH blocks.
5. The method of claim 4 , wherein the determining of the QCL shift indicator comprises receiving the QCL shift indicator through user-specific Radio Resource Control signalling.
6. The method of claim 4 , wherein the determining of the QCL shift indicator comprises receiving the QCL shift indicator through broadcast system information.
7. The method of claim 1 , comprising receiving an indication of a number of transmitted SS/PBCH blocks per burst.
8. The method of claim 7 , wherein the receiving of the indication of the number comprises receiving the number from a System Information Block (SIB).
9. The method of claim 8 , wherein the number is conveyed in a field used for ssb-PositionInBurst of a ServingCellConfigCommonSIB.
10. The method of claim 7 , wherein the receiving of the indication of the number comprises receiving the number from the MIB or PBCH payload, or the combination of the two.
11. The method of claim 7 , wherein the receiving of the indication of the number comprises receiving the number through user-specific Radio Resource Control signalling.
12. A wireless transceiver device arranged to operate in a cellular wireless communication network and capable of operating in a spectrum where listen-before-talk is employed, the wireless transceiver device comprising:
a transceiver arranged to receive and transmit signals, including receiving synchronisation signals and control signals; and
a signal handling circuit arranged to:
determine a first parameter indicative on provision of synchronisation signal blocks, the determining of the first parameter comprising receiving at least a part of the first parameter from a master information block (MIB) or physical broadcast channel (PBCH) payload, or a combination of the two; and
determine a quasi-co-location (QCL) relationship between two or more synchronisation signal and physical broadcast channel (SS/PBCH) blocks of a plurality of SS/PBCH blocks, each SS/PBCH block having a first index, the plurality of SS/PBCH blocks comprising at least a first SS/PBCH block and a second SS/PBCH block, the QCL relationship being determined to occur if at least a first result of a modulo operation of the first index of the first SS/PBCH block and the first parameter coincides with a second result of the modulo operation of the first index of the second SS/PBCH block and the first parameter.
13. The wireless transceiver device of claim 12 , wherein the signal handling circuit is further arranged to determine a frame timing based on the first index associated with a detected SS/PBCH block.
14. The wireless transceiver device of claim 12 , wherein determining the QCL relationship comprises:
determining one or more desired second indices from transmission history;
determining a second index for each one of two or more a received SS/PBCH blocks as the first index modulo the first parameter; and
comparing the second indices associated with at least two of the two or more received SS/PBCH blocks.
15. The wireless transceiver device of claim 12 , wherein the signal handling circuit is further arranged to determine a QCL shift indicator, and wherein the determining of the QCL relationship comprises:
determining one or more desired second indices from transmission history;
determining a second index for each one of two or more received SS/PBCH blocks as the first index modulo the first parameter minus the determined QCL shift when the second index becomes positive and as the first index modulo the first parameter minus the determined QCL shift plus the first parameter otherwise; and
comparing the second indices associated with at least two of the two or more received SS/PBCH blocks.
16. The wireless transceiver device of claim 15 , wherein determining the QCL shift indicator comprises receiving the QCL shift indicator through user-specific Radio Resource Control signalling.
17. The wireless transceiver device of claim 15 , wherein determining the QCL shift indicator comprises receiving the QCL shift indicator through broadcast system information.
18. The wireless transceiver device of claim 12 , wherein the signal handling circuit is further arranged to receive an indication of a number of transmitted SS/PBCH blocks per burst.
19. The wireless transceiver device of claim 18 , wherein the receiving of the indication of the number comprises receiving the number from a System Information Block (SIB).
20. The wireless transceiver device of claim 19 , wherein the number is conveyed in a field used for ssb-PositionInBurst of a ServingCellConfigCommonSIB.
21. The wireless transceiver device of claim 18 , wherein the receiving of the indication of the number comprises receiving the number from the MIB or PBCH payload, or the combination of the two.
22. The wireless transceiver device of claim 18 , wherein receiving the indication of the number comprises receiving the number through user-specific Radio Resource Control signalling.