Mitigation of external interference on an EGSM network

Wireless Technologies are being used extensively for telecommunication services, thus increasing the demand for frequency spectrum. Regulators are pushed to allocate spectrum efficiently resulting in increased possibility of interference. Interference management becomes a challenge if the same spectrum is allocated to different network operators in neighboring geographic areas. Operators generally use coordinated frequency/PN Offset planning to mitigate such interference. The problem becomes complicated if the adjacent geographic areas fall in different countries. ITU and Regional Regulatory bodies provide guidelines for coordinated spectrum allocations across international borders; however, some scenarios are not addressed. One such problem is faced by an EGSM operator in Pakistan which is facing severe interference from CDMA operators in India. Coordinated frequency/PN Offset planning is not possible in this cross-technology interference scenario. Furthermore, the effect of this interference is only observed on the EGSM side, while CDMA is not impacted. This paper describes the unique interference problem of the EGSM operator in Pakistan and describes a process adopted for analysis and mitigation of this interference.