Interference analysis for user equipment in LTE-Advanced system with carrier aggregation

Carrier aggregation (CA) is one of the most distinct techniques of Long Term Evolution-Advanced (LTE-Advanced) system because of its capability to support wide bandwidth while guaranteeing backward compatibility. In this paper, adjacent channel interference at user equipment (UE) in LTE-A system with CA is investigated. Due to the characteristics of orthogonal frequency division multiplexing (OFDM), slight variation of the frequency spacing between component carriers (CCs) and the adjacent channel interferer (ACI) results in different interference levels. This paper analyzed the impact of frequency spacing between CA signal and the ACI on the interference level. Moreover, utilizing the frequency response model of the Chebyshev filter, the relationship between the interference-resistance capability of LTE/LTE-A UE and the bandwidth of the receiver filter is studied. With the practical LTE-A system parameters, link level simulation results and the theoretical analysis match pretty well, and the analysis provide some guidelines for the UE design and standardization study of LTE-A.