Data scrambling in rate-split communications
Aspects provide communication methods, apparatuses and computer-readable mediums. According to an aspect, there is provided a method for wireless communication at a network entity. The method comprises: splitting a first individual message associated with a first device into at least a first common part and a first private part; splitting a second individual message associated with a second device into at least a second common part and a second private part; combining the first common part and the second common part to provide a common message; assigning a common group identifier to a group of devices comprising the first device and the second device; processing the common message, wherein the processing comprises scrambling the common message using the common group identifier; and transmitting the processed common message to the group of devices.
1. A method for wireless communication at a network entity, the method comprising:
splitting a first individual message associated with a first device into at least a first common part and a first private part;
splitting a second individual message associated with a second device into at least a second common part and a second private part;
combining the first common part and the second common part to provide a common message;
assigning a common group identifier to a group of devices comprising the first device and the second device;
processing the common message, wherein the processing comprises scrambling the common message using the common group identifier; and
transmitting the scrambled common message to the group of devices.
2. The method of claim 1 , wherein the common group identifier is configured using radio resource control.
3. The method of claim 1 , wherein:
the common group identifier is a cell identifier; and
the cell identifier is an identifier of cell provided by the network entity.
4. The method of claim 1 , wherein:
the common group identifier is offset from a cell identifier; and
the cell identifier is an identifier of cell provided by the network entity.
5. The method of claim 1 , wherein the common message is scrambled using the following equation:
cinit=nRNTI·215+ q· 214+NIDc
where
nRNTI is a radio network temporary identifier associated with the downlink control information scheduling the transmission of the scrambled common message,
q is an identifier to indicate that the equation relates to the common message, and
NIDc is the common group identifier.
6. The method of claim 5 , comprising generating the radio network temporary identifier prior to scrambling the common message, wherein the radio network temporary identifier is different to a cell radio network temporary identifier.
7. The method of claim 1 , comprising configuring a radio network temporary identifier, wherein the radio network temporary identifier is the same for the group of devices.
8. The method of claim 1 ,
comprising: generating the common group identifier,
wherein:
the common group identifier is different to a cell identifier; and
the cell identifier is an identifier of cell provided by the network entity.
9. The method of claim 1 , wherein processing the common message further comprises one or more of:
encoding the common message;
modulating the common message;
mapping the common message to one or more transmission layers; and
precoding the common message.
10. The method of claim 1 , comprising:
assigning a first identifier to the first device;
processing the first private part, wherein the processing comprises scrambling the first private part using the first identifier; and
transmitting the scrambled first private part to the first device.
11. The method of claim 10 , wherein the first private part is scrambled using the following equation:
cinit=nRNTI·215+ q· 214+ NID
where
nRNTI is a radio network temporary identifier associated with the downlink control information scheduling the transmission of the processed first private part,
q is a codeword index, and
NID is the first identifier.
12. The method of claim 11 , wherein the radio network temporary identifier is a cell radio network temporary identifier.
13. The method of claim 10 , wherein:
processing the first private part further comprises one or more of:
encoding the first private part;
modulating the first private part;
mapping the first private part to one or more transmission layers; and
precoding the first private part.
14. The method of claim 1 , comprising:
assigning a second identifier to the second device;
processing the second private part, wherein the processing comprises scrambling the second private part using the second identifier; and
transmitting the scrambled second private part to the second device.
15. The method of claim 14 , wherein:
processing the second private part further comprises one or more of:
encoding the second private part;
modulating the second private part;
mapping the second private part to one or more transmission layers; and
precoding the second private part.
16. The method of claim 1 , wherein:
the network entity is one of a plurality of network entities; and
the scrambled common message is transmitted to another network entity of the plurality of network entities.
17. A method for wireless communication at a wireless device, the method comprising:
receiving a first signal comprising a common message, wherein the common message comprises a first part of a rate-split message associated with the wireless device;
receiving a common group identifier;
processing the common message, wherein the processing comprises descrambling the common message using the common group identifier;
receiving a second signal comprising a private message, the private message comprising a second part of the rate-split message;
receiving a device identifier associated with the wireless device; processing the private message, wherein the processing comprises
descrambling the private message using the device identifier and the descrambled common message; and
decoding the rate-split message based at least in part on processing the common message and on processing the private message.
18. The method of claim 17 , wherein the common group identifier is configured using radio resource control.
19. The method of claim 17 , wherein the common group identifier is associated with a group of devices comprising the wireless device.
20. The method of claim 17 , wherein the common message and the common group identifier are received from a network entity.
21. The method of claim 17 , wherein descrambling the private part comprises using successive interference cancelation.
22. The method of claim 21 , wherein the successive interference cancelation comprises:
estimating an effective first channel corresponding to the received first signal;
reconstructing the descrambled common message to provide a reconstructed signal;
multiplying the reconstructed signal by the estimated effective channel to provide a multiplied signal;
subtracting the multiplied signal from the received first signal to provide a subtracted signal; and
descrambling the private part using the subtracted signal, the device identifier and the estimated effective second channel.
23. The method of claim 17 , comprising combining the descrambled common message and the processed private part of the rate-split message to provide an individual message associated with the wireless device.
24. The method of claim 17 , wherein the device identifier is received from a network entity and is different to the common group identifier.
25. The method of claim 17 , wherein the device identifier is configured using radio resource control.
26. The method of claim 17 , wherein the device identifier is uniquely associated with the wireless device.
27. The method of claim 17 , wherein:
the common group identifier is a cell identifier;
the cell identifier is an identifier of a cell provided by a network entity; and
the wireless device is located in the cell.
28. An apparatus for wireless communication at a network entity, the apparatus comprising:
means for splitting a first individual message associated with a first device into at least a first common part and a first private part;
means for splitting a second individual message associated with a second device into at least a second common part and a second private part;
means for combining the first common part and the second common part to provide a common message;
means for assigning a common group identifier to a group of devices comprising the first device and the second device;
means for processing the common message, wherein the processing comprises scrambling the common message using the common group identifier; and
means for transmitting the scrambled common message to the group of devices.
29. An apparatus for wireless communication at a wireless device, the apparatus comprising:
means for receiving a first signal comprising a common message, wherein the common message comprises a first part of a rate-split message associated with the wireless device;
means for receiving a common group identifier;
means for processing the common message, wherein the processing comprises descrambling the common message using the common group identifier;
means for receiving a second signal comprising a private message, the private message comprising a second part of the rate-split message;
means for receiving a device identifier associated with the wireless device; means for processing the private message, wherein the processing comprises
descrambling the private message using the device identifier and the descrambled common message; and
means for decoding the rate-split message based at least in part on processing the common message and on processing the private message.