Improving smartphone downlink performance and energy efficiency with 3-antenna receive diversity

3-antenna receive diversity is implemented within a smartphone form-factor to achieve gains in throughput (30% in median, 50% in the tail) and energy per bit over 2 antennas, with minimal increase to antenna volume even when supporting both low and high bands such as CELL (800 MHz) and PCS (1.9 GHz). Antenna designs are evaluated through simulations, and then integrated onto a smartphone prototype as well as commercial form-factor mockups. Downlink performance is measured on a commercial wireless network to account for real-world interference, traffic activity, and deployment topology, and field test results are further analyzed to determine gains in energy efficiency. Throughput gains agree with simulations, suggesting that full adoption of 3-antenna receive diversity could improve the capacity of existing wireless networks by 30-40%.