Co-channel interference mitigation on capacity and coverage in cellular systems

摘要

The Coverage and Capacity are the essential parameters that defines the performance of a cellular system. But, these are restricted by the interference in the system. The Co-Channel Interference(CCI) is one of the major sources of interference which exists mainly due to the concept of frequency reuse. The effect of CCI is more in CDMA based systems because the frequency reuse ratio is unity in those systems. In this paper, a new method is proposed to approximate capacity and coverage of a 3G WCDMA under the impact of CCI. The effect of CCI is described in terms of CCI probability. The conditional probability of CCI is analyzed under Rayleigh distributed signals. In this, COST 231 Hata model is described to calculate coverage area. The capacity and coverage are evaluated in terms of different number of Co-Channel interferers, antenna gain ratio, voice activity factor, Eb/No and with various data rates. It is shown that capacity increases with less number of active Co-Channel interferers and with low data rates. The cellular coverage area of WCDMA is improved by increasing the base station antenna height. The scheme proposed in this paper can also be successfully applied to evaluate capacity and coverage in 3GPP LTE and LTE Advanced systems.