Granted Patent B2

US 9,184,889 · App. 13/569,974 · Granted Nov 10, 2015

Abstract

Claims (38)

1. A method for providing reference signals to a user equipment from a network element, the method comprising:

determining a macro cell reference signal pattern;

determining a small cell reference signal pattern, the small reference signal pattern corresponding to the macro cell reference signal pattern with at least one punctured reference signal; and

sending the reference signals to the user equipment using a reference signal mapping;

wherein the reference signal mapping is based on the macro cell reference signal pattern if the user equipment is connected to a macro cell and based on the small cell reference signal pattern if the user equipment is connected to a small cell;

wherein a cell is a small cell if it has a lower transmission power than a macro cell.

2. The method of claim 1 , wherein the reference signal pattern provides for a density level of reference signals.

3. The method of claim 2 , wherein the reference signal mapping punctures reference signals for a lower density mapping.

4. The method of claim 3 , wherein the number of punctured reference signals varies based on the density level.

5. The method of claim 3 , wherein a location of unpunctured reference signals remains fixed in relation to the location of reference signals in a high density reference signal mapping.

6. The method of claim 3 , wherein a location of unpunctured reference signals changes for lower density reference signal mapping in relation to the location of reference signals in a high density reference signal mapping.

7. The method of claim 1 , further comprising signaling a lower density reference signal mapping to the user equipment, wherein the signaling provides for a mapping rule to indicate whether the reference signal mapping is fixed or flexible.

8. The method of claim 1 , further comprising signaling a lower density reference signal mapping to the user equipment, wherein the signaling provides for a value mapped to the reference signal pattern.

9. The method of claim 1 , further comprising signaling a lower density reference signal mapping to the user equipment, wherein the signaling comprises signaling a type of the network element.

10. The method of claim 1 , wherein the mapping is based on a common reference signal mapping.

11. The method of claim 1 , wherein the mapping is based on a code division multiplexing mapping.

12. The method of claim 1 , wherein the reference signal mapping is signaled from the network element to the user equipment and wherein the reference signal mapping for a secondary cell is signaled by a primary cell.

13. The method of claim 1 , wherein the reference signal mapping is signaled from the network element to the user equipment and wherein information on the reference signal mapping is embedded in a primary synchronization signal or secondary synchronization signal.

14. A network element for providing reference signals to a user equipment, the network element comprising:

a processor,

wherein the processor is configured to:

determine a macro cell reference signal pattern;

determine a small cell reference signal pattern, the small cell reference signal pattern corresponding to the macro cell reference signal pattern with at least one punctured reference signal; and

send the reference signals to the user equipment using a reference signal mapping;

wherein the reference signal mapping is based on the macro cell reference signal pattern if the user equipment is connected to a macro cell and based on the small cell reference signal pattern if the user equipment is connected to a small cell;

wherein a cell is a small cell if it has a lower transmission power than a macro cell.

15. The network element of claim 14 , wherein the reference signal pattern provides for a density level of reference signals.

16. The network element of claim 15 , wherein the reference signal mapping punctures reference signals for a lower density mapping.

17. The network element of claim 16 , wherein the number of punctured reference signals varies based on the density level.

18. The network element of claim 16 , wherein a location of unpunctured reference signals remains fixed in relation to the location of reference signals in a high density reference signal mapping.

19. The network element of claim 16 , wherein a location of unpunctured reference signals changes for lower density reference signal mapping in relation to the location of reference signals in a high density reference signal mapping.

20. The network element of claim 14 , wherein the processor is further configured to signal the lower density reference signal mapping to the user equipment using a mapping rule to indicate whether the reference signal mapping is fixed or flexible.

21. The network element of claim 14 , wherein the processor is further configured to signal the lower density reference signal mapping to the user equipment using a value mapped to the reference signal pattern.

22. The network element of claim 14 , wherein the processor is further configured to signal the lower density reference signal mapping to the user equipment using a type of the network element.

23. The network element of claim 14 , wherein the mapping is based on a common reference signal mapping.

24. The network element of claim 14 , wherein the mapping is based on a code division multiplexing mapping.

25. The network element of claim 14 , wherein the reference signal mapping is signaled from the network element to the user equipment and wherein the reference signal mapping for a secondary cell is signaled by a primary cell.

26. The network element of claim 14 , wherein the reference signal mapping is signaled from the network element to the user equipment and wherein information on the reference signal mapping is embedded in a primary synchronization signal or secondary synchronization signal.

Assignments (9)