Study of inter-system interference between region one and two cellular systems in the 2 GHz band

Frequency allocation in the 2 GHz band for cellular systems in region one and two has been made in overlapping bands. Due to this overlap in spectrum, there is potential for inter-system interference between the two regional cellular systems in region three where both systems are likely to coexist. This paper presents a study of the inter-system interference between region one and region two cellular systems. The performance degradation due to wide-band noise and receiver blocking are used to determine the minimum guard-band and minimum distance separation requirements for the coexistence of the two systems. The analysis shows that the performance degradation due to wide-band noise is the primary determinant of minimum guard-band and distance separation. A minimum guard-band of 3 MHz is required for the two cellular systems to operate reliably in the presence of inter-system interference. The degradation in quality at the cell boundary for a GSM 1800 mobile is determined by the practical minimum separation between mobile users. Generally the DAMPS and GSM 1800 base stations can be located at separate sites with distance separations to achieve the required quality. It is possible to co-locate DAMPS and GSM 1800 base station antennas with vertical separation, however it is not as practical to co-locate base station antennas with horizontal separation due to the large distance separations needed to achieve the required quality.