Suitability of RSRQ measurement for quality based inter-frequency handover in LTE

The purpose of this paper is to evaluate the suitability of reference signal received quality (RSRQ) measurement for quality based inter-frequency handover in UTRAN long term evolution (LTE). Intra-frequency handovers in LTE are done based on reference signal received power (RSRP) measurements, which should ensure that users are always connected to the cell with the highest received power. However, in certain environments where interference causes service quality degradation for the user (which RSRP measurement is not able to detect) there might be situation where a quality-based measurement would enable better system performance. In this paper, we evaluate the success and correctness of RSRQ based inter-frequency handovers as means for preventing service degradation using dynamic system simulations. However, comparison of RSRQ and RSRP based triggering suggest that RSRQ is not able to provide robust detection of service quality degradation. Furthermore, RSRQ is found to be heavily dependent on current system loading and the measurement strategy.