Novel SINR-to-CQI Mapping Maximizing the Throughput in HSDPA

The HSDPA extension of UMTS promises an improved cell capacity and throughput. This enhancement is mainly achieved by three newly introduced techniques, namely adaptive modulation and coding, hybrid automatic repeat request, and fast scheduling. The used coding and modulation scheme depends on the transmitted Transport Block Size, which in turn is signalled via the Channel Quality Indicator (CQI). The CQI values are calculated with the help of SINRs at each User Equipments and fed back to the base station. An appropriate CQI estimation is necessary to transmit data packets with Transport Block Sizes that maximize the throughput. Therefore, in this work we propose a novel SINR-to-CQI mapping which achieves optimum throughput for selected ITU propagation channel models.