Field Evaluation of the New Flexible LTE Transmission Mode

Transmission Mode 9 (TM9) is a key component in Release 10 of 3GPP Long Term Evolution (LTE). TM9 contains mobile individual Demodulation Reference Symbols (DMRS). DMRS increases the flexibility of radio resource utilization and opens for a plurality of features such as downlink beamforming and power control. This paper contains measurement results from a trial in a heterogeneous network deployment with a TM9 prototype implementation on a commercial system. It shows that TM9 improves downlink throughput significantly by itself in certain scenarios. An improvement of up to 0.4 bps/Hz is observed around cell edge and in the range expansion zone. This improvement comes from enhanced demodulation based on DMRS.