Cell identification information

1. A method in a network node for transmitting a cell identifier to identify a source for one or more beamed transmissions, the method comprising:

determining a cell identifier of the network node;

determining a beam identifier of a beam of the network node;

linking the cell identifier and the beam identifier; and

transmitting the beam identifier and the cell identifier to one or more user equipment, comprising dividing the cell identifier into a first sub-field and a second sub-field, the first sub-field is modulated separately from the second sub-field, wherein the cell identifier is transmitted with one or more resource elements with a demodulation reference signal derived from the beam identifier.

2. The method of claim 1 , wherein linking the cell identifier with the beam identifier comprises:

deriving a sequence from the beam identifier; and

scrambling the cell identifier with the sequence.

3. The method of claim 1 , wherein linking the cell identifier with the beam identifier comprises:

deriving a sequence from the beam identifier; and

scrambling a field associated with the transmitted cell identifier with the sequence.

4. The method of claim 1 , wherein the cell identifier is scrambled in a frequency domain.

5. The method of claim 1 , wherein the cell identifier is a sequence of encoded and quadrature amplitude modulated symbols.

6. The method of claim 1 , wherein the cell identifier is transmitted separately from the beam identifier transmission.

7. The method of claim 6 , wherein the cell identifier is transmitted over a physical downlink control channel.

8. The method of claim 7 , wherein the beam identifier maps to a radio network temporary identifier for receiving the physical downlink control channel.

9. The method of claim 1 , wherein the cell identifier is scheduled to be periodically transmitted to the one or more user equipment.

10. The method of claim 1 , further comprising configuring the one or more user equipment with a mapping between the cell identifier and the beam identifier.

11. The method of claim 1 , wherein linking the cell identifier with the beam identifier comprises selecting one or more of time/frequency resources, demodulation reference signal, and modulation level and coding scheme for cell identifier transmission based on the beam identifier.

12. The method of claim 1 , wherein the cell identifier transmission is performed in a same Orthogonal Frequency Division Multiplexing symbol as the beam identifier transmission.

13. A method in a user equipment (UE) for receiving a cell identifier to identify a source for one or more beamed transmissions comprising:

receiving a beam identifier from a network node; and

receiving a cell identifier linked to the beam identifier wherein the cell identifier is divided into a first sub-field and a second sub-field, the first sub-field is modulated separately from the second sub-field,

wherein the cell identifier is transmitted with one or more resource elements with a demodulation reference signal;

extracting a demodulation reference signal sequence derived from of the beam identifier;

estimating a channel using the one or more resource elements; and

demodulating the cell identifier.

14. The method of claim 13 , wherein the cell identifier is transmitted separately from a transmission of the beam identifier.

15. A network node for transmitting a cell identifier to identify a source for one or more beamed transmissions comprising:

a memory; and

a processor communicatively coupled to the memory, the processor configured to:

determine a cell identifier of the network node;

determine a beam identifier of a beam of the network node;

link the cell identifier and the beam identifier; and

transmit the beam identifier and the cell identifier to one or more user equipment, wherein transmitting the cell identifier comprises dividing the cell identifier into a first sub-field and a second sub-field, the first sub-field is modulated separately from the second sub-field, wherein the cell identifier is transmitted with one or more resource elements with a demodulation reference signal derived from the beam identifier.

16. The network node of claim 15 , wherein linking the cell identifier with the beam identifier comprises:

deriving a sequence from the beam identifier; and

scrambling the cell identifier with the sequence.

17. The network node of claim 15 , wherein linking the cell identifier with the beam identifier comprises:

deriving a sequence from the beam identifier; and

scrambling a field associated with the cell identifier with the sequence.

18. The network node of claim 15 , wherein the cell identifier is transmitted separately from the beam identifier transmission.

19. A user equipment for receiving a cell identifier to identify a source for one or more beamed transmissions comprising:

a memory; and

a processor communicatively coupled to the memory, the processor configured to:

receive a beam identifier from a network node;

receive a cell identifier linked to the beam identifier, wherein the cell identifier is divided into a first sub-field and a second sub-field, the first sub-field is modulated separately from the second sub-field and wherein the cell identifier is transmitted with one or more resource elements with a demodulation reference signal;

extract a demodulation reference signal sequence derived from the beam identifier;

estimate a channel using the one or more resource elements; and

demodulate the cell identifier.

20. The user equipment of claim 19 , wherein the processor is further configured to:

extract a scrambling sequence from a mobility reference signal associated with the beam identifier from the network node; and

descramble the cell identifier using the scrambling sequence.

21. The user equipment of claim 19 , wherein the cell identifier is scrambled in a frequency domain.

22. The user equipment of claim 19 , wherein the cell identifier is a sequence of encoded and quadrature amplitude modulated symbols.

23. The user equipment of claim 19 , wherein the cell identifier is transmitted separately from a transmission of the beam identifier.

24. The user equipment of claim 23 , wherein the cell identifier is transmitted over a physical downlink control channel.

25. The user equipment of claim 24 , wherein the beam identifier maps to a radio network temporary identifier for receiving the physical downlink control channel.

26. The user equipment of claim 19 , wherein the cell identifier is scheduled to be periodically transmitted to the user equipment.

27. The user equipment of claim 19 , wherein the user equipment is configured with a mapping between the cell identifier and the beam identifier.

28. The user equipment of claim 19 , wherein the processor is further configured to use the beam identifier and the cell identifier to estimate signal quality of a beam associated with the beam identifier.

29. The user equipment of claim 19 , wherein the processor is further configured to use the received cell identifier to group received mobility reference signals according to their originating cells.