Performance of closed access and open access femtocells in a heterogeneous LTE microcellular environment

In this paper, we investigate the performance of open access and closed access femtocell (HeNB) in the presence of a co-channel interference (CCI) from a nearby microcell base station (eNB). The analysis is presented for a downlink (DL) Long term Evolution (LTE) channel model in a heterogeneous network where there is no co-operation involved between eNB and HeNB. We further consider that the primary common pilot symbol (P-CPICH) is at least 20hdB higher at the user equipment (UE) to which it is connected so as to differentiate the useful signal from the interference. Our performance study indicates that a significant variation in bit error rate (BER) is observed when HeNB transmit power is varied and approximately 4dB gain in SNR is achievable when the eNB MUE link distance reduces from 700m to 500m.