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

Abstract

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-toindoor, 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.

Interference alignment over a combination of space and frequency

“…In order to evaluate performance for real-world path losses and channel correlations, we use channel measurements [15], [16]. The measurements were taken along a 70 m long office building corridor (see [15] for map) using an 20 MHz LTEAdvanced testbed with a carrier frequency of 2.7 GHz.…”

Resource allocation for licensed/unlicensed carrier aggregation MIMO systems

“…Furthermore, little work has been done concerning the application of the CA concept in MIMO systems [9]- [13]. Existing works are limited to the experimental evaluation of simple approaches that do not fully exploit the capabilities offered by a multi-antenna transceiver structure.…”

Comparing Theoretic Single-User and Multi-User Full-Dimension MIMO Data Throughputs in Realistic City-Wide LTE-A Deployments

“…Many papers, for example [4]- [6], have addressed SU-MIMO performance through simulation or measurement in LTE-A networks; in particular they address how much capacity improvement can be achieved using excess antenna elements at the base station. Our previous work [7] has demonstrated impressive capacity gain in both average cell throughput and cell-edge user throughputs in a 16Tx-8Rx system compared to an 8Tx-8Rx system in heterogeneous LTE-A deployments.…”