Synchronization signal block raster shift in mobile communications
Various examples with respect to synchronization signal block (SSB) raster shift in mobile communications are described. A processor of a user equipment (UE) performs an initial cell search to identify a cell among one or more cells of a wireless communication system. The processor then camps on the identified cell. In performing the initial cell search, the processor scans through a plurality of SSB entries for frequency bands below 3 GHz with a SSB raster spacing and a SSB raster offset frequency that support sub-carrier spacing (SCS) spaced channel raster and 100 kHz channel raster for both 15 kHz SCS and 30 kHz SCS. A minimum channel bandwidth at 5 MHz or higher for 15 kHz SCS or at 10 MHz or higher for 30 kHz SCS is supported. The SSB raster spacing is a common multiple of 15 kHz and 100 kHz. The SSB raster offset frequency for 100 kHz channel raster is a multiple of 30 kHz plus/minus 10 kHz.
1. A method, comprising:
performing, by a processor of a user equipment (UE), an initial cell search to identify a cell among one or more cells of a wireless communication system; and
camping, by the processor, on the identified cell,
wherein the performing of the initial cell search comprises scanning through a plurality of synchronization signal block (SSB) entries that are mathematically expressed as:
N *(900 kHz)+ M *(OkHz)+150 kHz
wherein a value of N ranges between 1 and 3333,
wherein a value of M is 0 for a sub-carrier spacing (SCS) spaced channel raster or one of −1, 0 and 1 for a 100 kHz channel raster,
wherein a value of O is one of 70, 80, 100, 110, 130, 140, 160, 170, 190, 200, 220, 230, 250, 260, 280 and 290, and
wherein a SSB raster spacing is a common multiple of 15 kHz and 100 kHz.
2. The method of claim 1 , wherein the scanning through the plurality of SSB entries comprises scanning through a subset of the plurality of SSB entries, and wherein the subset of the plurality of SSB entries is mathematically expressed as:
N *(1200 kHz)+ M *(50 kHz)
wherein the value of N ranges between 1 and 2499,
wherein the value of M is one of 1, 3 and 5, with the value of M being 3 for SCS spaced channel raster,
wherein a SSB raster spacing is 1200 kHz, and
wherein a SSB raster offset frequency is 100 kHz.
3. The method of claim 1 , wherein the scanning through the plurality of SSB entries comprises scanning through the plurality of SSB entries for frequency bands below 3 GHz for either or both of the SCS spaced channel raster and the 100 kHz channel raster.
4. The method of claim 1 , wherein a SSB raster offset frequency for the 100 kHz channel raster is a multiple of 30 kHz plus or minus 10 kHz.
5. The method of claim 4 , wherein the SSB raster offset frequency is 20 kHz, 40 kHz, 50 kHz, 70 kHz, 80 kHz or 100 kHz.
6. The method of claim 4 , wherein a minimum of the SSB raster offset frequency is higher than two times of a highest frequency offset of by inaccuracy of a reference clock of the UE.
7. The method of claim 4 , wherein a maximum of the SSB raster offset frequency is lower than one third of a SSB raster spacing.
8. The method of claim 1 , wherein the SCS spaced channel raster comprises a SCS spaced channel raster with 15 kHz SCS.
9. The method of claim 8 , wherein a minimum channel bandwidth is 5 MHz or higher.
10. The method of claim 1 , wherein the SCS spaced channel raster comprises a SCS spaced channel raster with 30 kHz SCS.
11. The method of claim 10 , wherein a minimum channel bandwidth is 10 MHz or higher.
12. The method of claim 1 , wherein the SSB raster spacing is one of 300 kHz, 600 kHz, 900 kHz and 1200 kHz.
13. A method, comprising:
performing, by a processor of a user equipment (UE), an initial cell search to identify a cell among one or more cells of a wireless communication system; and
camping, by the processor, on the identified cell,
wherein the performing of the initial cell search comprises scanning through a plurality of synchronization signal block (SSB) entries for frequency bands below 3 GHz with a SSB raster spacing and a SSB raster offset frequency satisfying a plurality of requirements comprising:
support for either or both of a sub-carrier spacing (SCS) spaced channel raster and a 100 kHz channel raster,
support for both 15 kHz SCS and 30 kHz SCS for the SCS spaced channel raster,
a minimum channel bandwidth (CBW) at 5 MHz or higher for 15 kHz SCS or at 10 MHz or higher for 30 kHz SCS,
the SSB raster spacing being a common multiple of 15 kHz and 100 kHz, and
the SSB raster offset frequency for the 100 kHz channel raster being a multiple of 30 kHz plus or minus 10 kHz.
14. The method of claim 13 , wherein the plurality of SSB entries are mathematically expressed as:
N *(900 kHz)+ M *(OkHz)+150 kHz
wherein a value of N ranges between 1 and 3333,
wherein a value of M is 0 for a sub-carrier spacing (SCS) spaced channel raster or one of −1, 0 and 1 for a 100 kHz channel raster, and
wherein a value of O is one of 70, 80, 100, 110, 130, 140, 160, 170, 190, 200, 220, 230, 250, 260, 280 and 290.
15. The method of claim 13 , wherein the plurality of SSB entries are mathematically expressed as:
N *(1200 kHz)+ M *(50 kHz)
wherein a value of N ranges between 1 and 2499,
wherein a value of M is one of 1, 3 and 5, with the value of M being 3 for SCS spaced channel raster,
wherein the SSB raster spacing is 1200 kHz, and
wherein the SSB raster offset frequency is 100 kHz.
16. The method of claim 13 , wherein a minimum of the SSB raster offset frequency is higher than two times of a highest frequency offset of by inaccuracy of a reference clock of the UE.
17. The method of claim 13 , wherein a maximum of the SSB raster offset frequency is lower than one third of the SSB raster spacing.
18. An apparatus, comprising:
a transceiver that, when in operation, wirelessly communicates with one or more cells of a wireless communication system; and
a processor coupled to the transceiver such that, when in operation, the processor performs operations comprising:
performing, via the transceiver, an initial cell search to identify a cell among the one or more cells of the wireless communication system; and
camping, via the transceiver, on the identified cell,
wherein, in performing the initial cell search, the processor scans through a plurality of synchronization signal block (SSB) entries that are mathematically expressed as:
N *(900 kHz)+ M *(OkHz)+150 kHz
wherein a value of N ranges between 1 and 3333,
wherein a value of M is 0 for a sub-carrier spacing (SCS) spaced channel raster or one of −1, 0 and 1 for a 100 kHz channel raster,
wherein a value of O is one of 70, 80, 100, 110, 130, 140, 160, 170, 190, 200, 220, 230, 250, 260, 280 and 290,
wherein, in scanning through the plurality of SSB entries, the processor scans through a subset of the plurality of SSB entries, and wherein the subset of the plurality of SSB entries is mathematically expressed as:
N *(1200 kHz)+ M *(50 kHz)
wherein the value of N ranges between 1 and 2499,
wherein the value of M is one of 1, 3 and 5, with the value of M being 3 for SCS spaced channel raster,
wherein a SSB raster spacing is 1200 kHz, and
wherein a SSB raster offset frequency is 100 kHz.