HSPA+ (2100 MHz) vs LTE (2600 MHz) spectral efficiency and latency comparison

High Speed Packet Access+ (HSPA+) has become widely deployed whilst the more recently specified Long Term Evolution (LTE) deployments are in their infancy. The objective of this paper is to provide a side by side field performance comparison between HSPA+ and LTE deployed in the 2100 MHz and 2600 MHz bands respectively reusing the same sites and antennas and using the most advanced mobile broadband feature readily available in the same radio environment. Separately, both of these technologies have been investigated however a comparison of both as part of the same field trial has received less attention. The performance comparison was carried out with comparable spectrum bandwidth (5 and 10 MHz) in a real network - Vodafone Spain - dedicated to the trial without any bias in terms of traffic or interference from other users. The exercise revealed that the latency performance difference is not as high as expected with less than 10 ms difference however the connection time is significantly improved. Most distinguishing factor in LTE downlink is the more efficient and robust usage of Multiple Input Multiple Output (MIMO) and 64 Quadrature Amplitude Modulation (QAM) altogether which outperforms HSPA+ even when using a less advantageous frequency band. In uplink LTE only outperforms HSPA+ in good radio conditions due to the possibility to use 16QAM modulation.