System and Method for Parameter Estimation with Interference Suppression in a Telecommunications Network

• US 20100278047A1
• Filed: 02/02/2010
• Published: 11/04/2010
• Est. Priority Date: 05/04/2009
• Status: Abandoned Application

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Guey, Jiann-Ching, Koorapaty, Havish
• Application Number:
  US12/698,798
• Publication Number:
  US 20100278047A1
• Time in Patent Office: Days
• US Class Current: 370/241
• CPC Class Codes: H04L 25/0204 of multiple channels
• CPC Class Codes: H04L 25/0224 using sounding signals
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04W 36/385 of the core network

Abstract

A system, method and node of implementing interference suppression for estimation of a signal parameter of a base station transmission at a User Equipment (UE) in a telecommunications network with irregular reference signal patterns assigned to base stations. A list of base stations for which a parameter of the transmitted signal is to be estimated and a list of OFDM symbols and subcarriers to avoid for each base station are compiled. The compiled list is sent to the UE, which performs measurements for each base station using the received measurement information and simple interference avoidance is performed utilizing OFDM symbols and subcarriers not on the list of OFDM symbols and subcarriers to avoid. The measurements are then sent to the network.

Claims

1. A method of estimating a parameter of a signal transmitted by a base station in a telecommunications network, the method comprising the steps of:

assigning irregular reference signal patterns to a plurality of base stations;

compiling a list of base stations from the plurality of base stations for which a parameter of the transmitted signal is to be estimated;

determining a list of Orthogonal Division Frequency Multiplexing (OFDM) symbols and subcarriers to avoid for each base station to be measured;

performing measurements for each base station of the compiled list based on the received measurement information, wherein simple interference avoidance is performed by utilizing OFDM symbols and subcarriers not on the list of OFDM symbols and subcarriers to avoid.

2. The method according to claim 1 further comprising the network sending the compiled list of base stations to measure and list of OFDM symbols and subcarriers to avoid, as measurement information.

3. The method according to claim 1 further comprising sending the measured signal parameters to the telecommunications network for further processing.

4. The method according to claim 1, wherein the irregular reference signal patterns intersect minimally with the irregular reference signal patterns from other base stations.

5. The method according to claim 1, wherein a TOA measurement is used to estimate a position of the UE.

6. The method according to claim 1, wherein the step of performing measurements includes:

modifying a signal s[q] by setting to zero the parts of the signal corresponding to subcarriers and OFDM symbols that are to be avoided; and

performing measurements using the modified signal s[q].

7. The method according to claim 5, wherein the step of performing TOA measurements includes performing partial correlations for each OFDM symbol within the received signal.

8. The method according to claim 7, wherein the step of performing partial correlations includes generating outputs b_i[t] from the partial correlations and setting b_i[t] to zero for OFDM symbols having a specified high energy output.

9. The method according to claim 1, wherein the parameter of the signal estimated is one or more of;

the received power of the signal, Time of Arrival, received signal strength and a complex channel estimate.

10. A system for estimating a parameter of a signal transmitted by a base station in a telecommunications network, the system comprising:

a UE requesting information for estimating the parameter of the signal;

network means for assigning irregular reference signal patterns to a plurality of base stations;

a node for compiling a list of base stations from the plurality of base stations for which a parameter of the transmitted signal is to be estimated; and

means in the node for determining a list of Orthogonal Division Frequency Multiplexing (OFDM) symbols and subcarriers to avoid for each base station to be measured; and

means for performing measurements for each base station of the compiled list based on the received measurement information, wherein simple interference avoidance is performed by utilizing OFDM symbols and subcarriers not on the list of OFDM symbols and subcarriers to avoid.

11. The system of claim 10 further comprising transmitting means for sending the compiled list of base stations to measure and a list of OFDM symbols and subcarriers to avoid as measurement information to the UE.

12. The system of claim 10, further comprising means for sending the measurement information to the telecommunications network.

13. The system according to claim 10, wherein the irregular reference signal patterns intersect minimally with the irregular reference signal patterns from other base stations.

14. The system according to claim 10, wherein a TOA measurement is used to estimate a position of the UE.

15. The system according to claim 10, wherein the means for performing measurements includes:

means for modifying a signal s[q] by setting the parts of the signal corresponding to subcarriers and OFDM symbols to zero that are to be avoided; and

means for performing measurements using the modified signal s[q].

16. The system according to claim 10, wherein the means for sending the measurements to the telecommunications network includes means for sending the measurements to an eNodeB.

17. The system according to claim 14, wherein the means for performing time of arrival measurements includes means for performing partial correlations for each OFDM symbol within the received signal.

18. The system according to claim 17, wherein the means for performing partial correlations includes means for generating outputs b_i[t] from the partial correlations and setting b_i[t] to zero for OFDM symbols having a specified high energy output.

19. The system according to claim 10, wherein the parameter of the signal estimated is one or more of;

the received power of the signal, Time of Arrival, received signal strength and a complex channel estimate.

20. A node for providing assistance information for estimating a parameter of a signal transmitted by a base station in a telecommunications network, the node comprising:

means for assigning irregular reference signal patterns to a plurality of base stations;

means for compiling a list of base stations from the plurality of base stations to measure for determining an estimate of the parameter of the signal;

means for determining a list of Orthogonal Division Frequency Multiplexing, OFDM, symbols and subcarriers to avoid for each base station to be measured; and

means for sending the compiled list of base stations to measure and list of OFDM symbols and subcarriers to avoid as measurement information to the UE.

21. The node according to claim 20, wherein the irregular reference signal patterns intersect minimally with patterns from each of the plurality of base stations.

22. The node according to claim 20, wherein the parameter of the signal is a Time of Arrival (TOA) measurement, which is used to estimate a position of the UE.

23. The node according to claim 20, wherein the parameter of the signal estimated is one or more of the Time of Arrival, received signal strength and a complex channel estimate.

24. A User Equipment (UE) for estimating a parameter of a signal transmitted by a base station in a telecommunications network, the UE comprising:

means for making measurements wherein simple interference avoidance is performed by utilizing only some of the OFDM symbols and subcarriers.

25. The UE of claim 24, further comprising means for receiving information comprising a complied list of base stations to measure and a list of Orthogonal Division Frequency Multiplexing (OFDM) symbols and subcarriers to avoid for each base station to be measured.

26. The UE of claim 24, further comprising means for requesting information for estimating the parameter of the signal and means for sending the measurements to the telecommunications network.

27. The UE according to claim 26 wherein the parameter of the signal is one or more of the, Time of Arrival, received signal strength and a complex channel estimate.

28. The UE according to claim 24 wherein the means for performing measurements includes:

means for modifying a signal s[q] by setting to zero the parts of the signal corresponding to subcarriers and OFDM symbols that are to be avoided; and

means for performing measurements using the modified signal s[q].

29. The UE according to claim 25 wherein a means for performing time of arrival measurements includes means for performing partial correlations for each OFDM symbol within the received signal and

means for generating outputs b_i[t] from the partial correlations.

30. The UE according to claim 28 wherein the means for generating outputs b_i[t] includes setting b_i[t] to zero for OFDM symbols having a specified high energy output.