Capacity degradation due to coexistence between second generation and 3G/WCDMA systems

This paper evaluates the capacity degradation due to the coexistence of a 3G/WCDMA system with second-generation systems in the North American PCS band. The performance impact of deploying 3G FDD and 2G systems on adjacent frequency bands (not overlapping) in the same block with the same FDD directionality is studied. The methodology is based on the elaboration of a multi-cell system-level simulation tool that allows a quantitative assessment of the change of capacity due to the presence of another wireless system operating in an adjacent band. This simulation tool follows generally agreed principles and assumptions as proposed by 3GPP with some additional assumptions related to the North American second-generation system (GSM, IS-136 and IS-95). The main results of this study are that in most cases, the 2G system is found to be the aggressor and the 3G system the victim, and that the worst-case deployment is an un-coordinated one, which requires improvement in power budget of 30 dB (assuming no guard-band).