Methods and apparatus in a wireless communication system
The present invention relates to methods and apparatus in a RBS and a UE for reference signal (RS) measurements in an OFDM system, that enable having a configurable RS transmission bandwidth which is smaller than the system bandwidth. This allows for better interference coordination of RS, which in turn improves the UE RS measurements used for different services such as positioning. The RBS retrieves the RS transmission bandwidth, determines a RS measurement bandwidth based on this RS transmission bandwidth, and transmits the determined bandwidth to the UE. The UE receives the RS measurement bandwidth and measures the RS in a bandwidth determined based on the received measurement bandwidth and the UE capability.
1. A user equipment configured for use in a wireless communication system, the user equipment comprising:
a receiver configured to receive assistance data that includes identities of one or more cells neighboring a serving cell of the user equipment and that includes information indicating a positioning reference signal (PRS) bandwidth for a cell, wherein the PRS bandwidth indicated for the cell is configurable to be smaller than a bandwidth over which the cell transmits PRS; and
a measuring circuit configured to measure PRS for the cell in a bandwidth determined to be smaller than the PRS bandwidth indicated for the cell.
2. The user equipment of claim 1 , wherein the measuring circuit is configured to measure PRS for the cell in a bandwidth determined based on the PRS bandwidth indicated for the cell and based on a bandwidth over which the user equipment is capable of measuring.
3. The user equipment of claim 1 , wherein the measuring circuit is configured to measure PRS for the cell in a bandwidth determined as a minimum of a set of bandwidths, wherein the set of bandwidths includes the PRS bandwidth for the cell and a bandwidth over which the user equipment is capable of measuring.
4. The user equipment of claim 1 , wherein the measuring circuit is configured to measure PRS for the cell in a bandwidth determined based on the PRS bandwidth indicated for the cell and based on a system bandwidth applicable for the cell.
5. The user equipment of claim 1 , wherein the measuring circuit is configured to measure PRS for the cell in a bandwidth determined as a minimum of a set of bandwidths, wherein the set of bandwidths includes the PRS bandwidth for the cell and a system bandwidth applicable for the cell.
6. The user equipment of claim 1 , wherein the PRS bandwidth indicated for the cell is configurable to be smaller than a system bandwidth applicable for the cell.
7. The user equipment of claim 1 , wherein the measuring circuit is configured to measure PRS for the cell as part of performing an observed time difference of arrival (OTDOA) positioning measurement.
8. The user equipment of claim 1 , wherein the assistance data is received from a positioning server using a Long Term Evolution (LTE) Positioning Protocol (LPP).
9. A method performed by a user equipment configured for use in a wireless communication system, the method comprising:
receiving assistance data that includes identities of one or more cells neighboring a serving cell of the user equipment and that includes information indicating a positioning reference signal (PRS) bandwidth for a cell, wherein the PRS bandwidth indicated for the cell is configurable to be smaller than a bandwidth over which the cell transmits PRS; and
measuring PRS for the cell in a bandwidth determined to be smaller than the PRS bandwidth indicated for the cell.
10. The method of claim 9 , wherein the measuring comprises measuring PRS for the cell in a bandwidth determined based on the PRS bandwidth indicated for the cell and based on a bandwidth over which the user equipment is capable of measuring.
11. The method of claim 9 , wherein the measuring comprises measuring PRS for the cell in a bandwidth determined as a minimum of a set of bandwidths, wherein the set of bandwidths includes the PRS bandwidth for the cell and a bandwidth over which the user equipment is capable of measuring.
12. The method of claim 9 , wherein the measuring comprises measuring PRS for the cell in a bandwidth determined based on the PRS bandwidth indicated for the cell and based on a system bandwidth applicable for the cell.
13. The method of claim 9 , wherein the measuring comprises measuring PRS for the cell in a bandwidth determined as a minimum of a set of bandwidths, wherein the set of bandwidths includes the PRS bandwidth for the cell and a system bandwidth applicable for the cell.
14. The method of claim 9 , wherein the PRS bandwidth indicated for the cell is configurable to be smaller than a system bandwidth applicable for the cell.
15. The method of claim 9 , wherein the measuring comprises measuring PRS for the cell as part of performing an observed time difference of arrival (OTDOA) positioning measurement.
16. The method of claim 9 , wherein the assistance data is received from a positioning server using a Long Term Evolution (LTE) Positioning Protocol (LPP).