Signaling approaches for new radio in the unlicensed spectrum
The exemplary embodiments relate to signaling between a user equipment (UE) and a cell over the unlicensed spectrum. The UE may receive a signal broadcast by a cell of the network over a channel in the unlicensed spectrum. The signal includes a set of channel state information reference signals (CSI-RS) each corresponding to a set of synchronization signal blocks (SSB) and is transmitted during a discovery reference signal (DRS) window. The UE may then determine a location of the set of CSI-RS within the DRS window and perform an operation based on the set of CSI-RS.
1. A computer readable storage medium comprising a set of instructions, wherein the set of instructions when executed by a processor of a user equipment (UE) causes the processor to perform operations, comprising:
receiving a signal broadcast by a cell of a network over a channel in the unlicensed spectrum, wherein the signal includes a set of channel state information reference signals (CSI-RS) each corresponding to a set of synchronization signal blocks (SSB) and is transmitted during a discovery reference signal (DRS) window;
determining a location of the set of CSI-RS within the DRS window;
performing an operation based on the set of CSI-RS;
determining that a first CSI-RS is quasi co-located (QCLed) with one or more further CSI-RS; and
determining that the one or more CSI-RS are not transmitted by the cell based on determining that the presence of the first CSI-RS that is QCLed with the one or more further CSI-RS in the DRS window, wherein the first CSI-RS transmissions is assumed to be QCLed based on N CSI-RS mod N CSI-RS QCL , wherein N CSI-RS (0≤N CSI-RS <M) represents a CSI-RS index within the DRS window and N CSI-RS QCL represents a number of non-QCLed N CSI-RS and is provided by the network in a system information block 1 (SIB1) or a physical broadcast channel (PBCH), wherein M represents a predetermined number of CSI-RS.
2. The computer readable storage medium of claim 1 , wherein determining the location of the set of CSI-RS is based on a first offset parameter and a second offset parameter.
3. The computer readable storage medium of claim 2 , wherein the first offset parameter is a symbol offset associated with a first CSI-RS and a first SSB located within the same orthogonal frequency-division multiplying (OFDM) symbol.
4. The computer readable storage medium of claim 2 , wherein the second offset parameter is a resource block (RB) offset associated with a first CSI-RS and a first SSB.
5. The computer readable storage medium of claim 4 , wherein the (RB) offset is defined relative to the lowest RB of the first SSB or the highest RB of the first SSB.
6. The computer readable storage medium of claim 1 , wherein determining the location of the set of CSI-RS is based on determining a frequency domain occupation of the CSI-RS resources within the DRS window.
7. The computer readable storage medium of claim 6 , wherein the frequency domain occupation of the CSI-RS resources within the DRS window is determine based on a bandwidth associated with a listen-before-talk (LBT) operation and a bandwidth associated with the set of SSB.
8. The computer readable storage medium of claim 1 , wherein determining the location of the set of CSI-RS is based on a bitmap included in a system information block (SIB).
9. The computer readable storage medium of claim 1 , the operations further comprising:
initializing a pseudo-random sequence of QCLed CSI-RS (r(m)) at a start of each OFDM symbol and apply it to all QCLed SI-RS within the DRS window, wherein initializing is based
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wherein N symb slot represents a number of a slot and a symbol within the slot of a radio frame, n s,f μ is a slot number within the radio frame, l is a OFDM symbol number within a slot for a transmission occasion within a first N CSI-RS QCL transmission occasion and n ID is configured by higher layers.
10. The computer readable storage medium of claim 1 , the operations further comprising:
receiving a first Downlink Control Information (DCI) format to determine physical random access channel (PRACH) resource allocation within a channel occupation time (COT) indicated by a second DCI format.
11. The computer readable storage medium of claim 10 , wherein the first DCI and the second DCI are DCI format 2_0.
12. The computer readable storage medium of claim 10 , wherein the first DCI is DCI format 1_1 and the second DCI is DCI format 2_0.
13. The computer readable storage medium of claim 10 , wherein physical random access channel (PRACH) resources are allocated based on a row index of an allocation Table that is configured by SIB1 or preconfigured.
14. A user equipment (UE), comprising:
a transceiver configured to communicate with a network; and
a processor configured to perform operations, the operations comprising:
receiving a signal broadcast by a cell of the network over a channel in the unlicensed spectrum, wherein the signal includes a set of channel state information reference signals (CSI-RS) each corresponding to a set of synchronization signal blocks (SSB) and is transmitted during a discovery reference signal (DRS) window;
determining a location of the set of CSI-RS within the DRS window;
performing an operation based on the set of CSI-RS,
determining that a first CSI-RS is quasi co-located (QCLed) with one or more further CSI-RS; and
determining that the one or more CSI-RS are not transmitted by the cell based on determining that the presence of the first CSI-RS that is QCLed with the one or more further CSI-RS in the DRS window, wherein the first CSI-RS transmissions is assumed to be QCLed based on N CSI-RS mod N CSI-RS QCL , wherein N CSI-RS (0≤N CSI-RS <M) represents a CSI-RS index within the DRS window and N CSI-RS QCL represents a number of non-QCLed N CSI-RS and is provided by the network in a system information block 1 (SIB1) or a physical broadcast channel (PBCH), wherein M represents a predetermined number of CSI-RS.
15. The UE of claim 14 , wherein determining the location of the set of CSI-RS is based on a first offset parameter and a second offset parameter.
16. The UE of claim 15 , wherein the first offset parameter is a symbol offset associated with a first CSI-RS and a first SSB located within the same orthogonal frequency-division multiplying (OFDM) symbol.
17. The UE of claim 15 , wherein the second offset parameter is a resource block (RB) offset associated with a first CSI-RS and a first SSB and wherein the (RB) offset is defined relative to the lowest RB of the first SSB or the highest RB of the first SSB.
18. The UE of claim 14 , the operations further comprising:
receiving a first Downlink Control Information (DCI) format to determine physical random access channel (PRACH) resource allocation within a channel occupation time (COT) indicated by a second DCI format.
19. The UE of claim 18 , wherein (i) the first DCI and the second DCI are DCI format 2_0 or (ii) the first DCI is DCI format 1_1 and the second DCI is DCI format 2_0.
20. The UE of claim 18 , wherein physical random access channel (PRACH) resources are allocated based on a row index of an allocation Table that is configured by SIB1 or preconfigured.