Field experiments on throughput performance of carrier aggregation with asymmetric bandwidth in LTE-advanced

This paper presents field experimental results on the block error rate (BLER) of uplink control information (UCI) and the downlink throughput performance of carrier aggregation (CA) with an asymmetric bandwidth between the downlink and uplink using implemented LTE-Advanced transceivers with the center carrier frequencies of 3.92625 and 3.67125 GHz in the downlink and uplink, respectively. The field experimental results confirm that when the UCI, i.e., channel quality indicator (CQI), for the purpose of downlink adaptive modulation and coding (AMC) is multiplexed with the uplink data signal, the required BLER of the UCI is almost satisfied. The results also show that when CA with 5 component carriers (CCs) (100-MHz bandwidth) and 2-by-2 single-user (SU) multiple-input multiple-output (MIMO) are applied in the downlink, the throughput of greater than 500 Mbps (peak throughput of approximately 640 Mbps) is achieved even when UCI (CQI) error is considered. Furthermore, in an urban area in Sagamihara city near Tokyo, the field experimental results show that the throughput of greater than 100 Mbps is observed in certain areas at the distance from the BS antenna of over 1 km using the center carrier frequency of 3.92625 GHz.