Claims:WE CLAIMS
1 A method for resolution of collision of Physical Cell Identifier (PCI) between a plurality of base stations, the method comprising:
determining, by a PCI Collision Detection and Resolution Module (PCDRM), a value of a Physical Cell Identifier Collision Margin (PCICM);
detecting, by the PCDRM, a PCI collision among a plurality of base stations based on the determined PCICM value, wherein the plurality of base stations comprises a Serving Base Station (SBS) and one or more Neighboring Base Stations (NBS);
estimating, by the PCDRM, a relative distance between the SBS and each of the one or more NBS; and
reconfiguring, by the PCDRM, a new PCI value associated with the SBS based on the estimated relative distance.
2 The method of claim 1, wherein estimating the relative distance between the SBS and each of the one or more NBS is based on a reference signal received power (RSRP) value and a reference signal received quality (RSRQ) value measured by one or more User Equipment (UE)(s) for each of the one or more NBS.

3 The method of claim 2, wherein the determination of the value of PCICM is based on a distribution of the one or more UE(s), the RSRP value(s), and the RSRQ value(s) measured by the one or more UE(s).

4 The method of claim 2, further comprising:
receiving the RSRP value(s) and the RSRQ value(s) from the one or more UE(s);
comparing the received RSRP value(s) and RSRQ value(s) with a pre-defined threshold RSRP value (RSRPth) and a threshold RSRQ value (RSRQth), respectively; and
adjusting the PCICM value based on the comparison.
5 The method of claim 2, further comprising determining average interference (INTRFavg) for the RSRP value(s).

6 The method of claim 1, wherein the new PCI value for the SBS is selected from at least one NBS among a plurality of NBS(s) for which an effective RSRP value is greater than an effective RSRQ value.

7 The method of claim 1, wherein the reconfiguring of the new PCI value comprises:
selecting a temporary PCI value from one of PCI values associated with the plurality of NBS;
determining whether the selected temporary PCI value resolves the detected collision based on a maximum difference in RSRP values and a maximum difference in RSRQ values, wherein on determination of resolution of the collision, the selected temporary PCI value is assigned as the new PCI value to the SBS.
8 The method of claim 1 wherein, detecting the PCI collision among the plurality of base stations is done when the difference between an effective interference (INTRFeff) and an interference margin (INTRFmargin) is greater than a threshold interference margin (INTRFmarginTH).

9 The method of claim 1, further comprising determining a maximum power transmit (TXPowMaxFinal) for the SBS with the new PCI value based on a threshold received power ( ) and a power hysteresis (?TH_CELL).
10 A system for resolution of collision of Physical Cell Identifier (PCI) between a plurality of base stations, the system comprising:
a processor; and
a memory communicatively coupled to the processor, wherein the memory stores processor instructions, which, on execution, causes the processor to:
determine a value of a Physical Cell Identifier Collision Margin (PCICM);
detect a PCI collision among a plurality of base stations based on the determined PCICM value, wherein the plurality of base stations comprises a Serving Base Station (SBS) and one or more Neighbouring Base Stations (NBS);
estimate a relative distance between the SBS and each of the one or more NBS; and
reconfigure a new PCI value associated with the SBS based on the estimated relative distance.

11 The system of claim 10, wherein estimating the relative distance between the SBS and each of the one or more NBS is based on a reference signal received power (RSRP) value and a reference signal received quality (RSRQ) value measured by one or more User Equipment (UE)(s) for each of the one or more NBS.

12 The system of claim 11, wherein the determination of the value of PCICM is based on a distribution of the one or more UE(s), the RSRP value(s), and the RSRQ value(s) measured by the one or more UE(s).

13 The system of claim 11, wherein the processor is further configured to:
receive the RSRP value(s) and the RSRQ value(s) from the one or more UE(s);
compare the received RSRP value(s) and RSRQ value(s) with a pre-defined threshold RSRP value (RSRPth) and a threshold RSRQ value (RSRQth), respectively; and
adjust the PCICM value based on the comparison.
14 The system of claim 11, wherein the processor is further configured to determine average interference (INTRFavg) for the RSRP value(s).

15 The system of claim 10, wherein the new PCI value for the SBS is selected from at least one NBS among a plurality of NBS(s) for which an effective RSRP value is greater than an effective RSRQ value.

16 The system of claim 10, wherein the reconfiguring of the new PCI value comprises:
selecting a temporary PCI value from one of PCI values associated with the plurality of NBS;
determining whether the selected temporary PCI value resolves the detected collision based on a maximum difference in RSRP values and a maximum difference in RSRQ values, wherein on determination of resolution of the collision, the selected temporary PCI value is assigned as the new PCI value to the SBS.
17 The system of claim 10, wherein, detecting the PCI collision among the plurality of base stations is done when the difference between an effective interference (INTRFeff ) and an interference margin (INTRFmargin) is greater than a threshold interference margin (INTRFmarginTH).

18 The system of claim 10, further comprising determining a maximum power transmit (TXPowMaxFinal) for the SBS with the new PCI value based on a threshold received power ( ) and a power hysteresis (?TH_CELL).

Dated this 13th day of January 2017
R Ramya Rao
Of K&S Partners
Agent for the Applicant
, Description:TECHNICAL FIELD
The present subject matter is related, in general to wireless communications, and, particularly, but not exclusively to a method and a system for Physical Cell Identifier (PCI) collision detection and resolution.