LTE-A Field Measurements: 8x8 MIMO and Carrier Aggregation

The introduction of 8x8 MIMO and carrier aggregation in the 3GPP LTE Rel. 10 opens up for increased user throughput. The potential gains using these techniques have been evaluated in a field measurement campaign with a testbed implementation. A downlink throughput exceeding 1 Gbps has been achieved combining 8x8 MIMO in an outdoor macro scenario with carrier aggregation using three component carriers (3x20 MHz). The relation between the achievable throughput and the channel richness arising from the physical environment and antenna spacing was demonstrated. The performance of MIMO setups ranging from 1x2 up to 8x8 was evaluated in indoor-to-indoor, outdoor-to-indoor, and outdoor-to-outdoor deployments. It was observed that each added transmit or receive antenna increased the throughput. These gains were achieved with a compact UE antenna that is reasonable in size for implementation in a consumer device.