Energy-efficient architectures for time-critical LTE protocol stack algorithms in mobile terminals

The evolution of mobile communication systems aims at higher data rates in order to better support data-demanding mobile applications such as video streaming. The new Long Term Evolution (LTE) and LTE-Advanced (LTE-A) standards provide downlink transmission speeds of up to 300 Mbit/s and 3 Gbit/s, respectively. To cope with such high data rates the processing of the modem protocol stack must be performed within tight timing constraints. Furthermore, protocol processing must be implemented to consume a minimal amount of energy in order to enable a longer battery lifetime. Additionally, as more and more features are being integrated in mobile handsets, area-optimized designs are also required to reduce chip costs. Due to these design challenges new architectural solutions targeting the challenging protocol processing speed requirements are investigated and explored in this thesis. This work addresses the time-critical algorithms in the modem pro-tocol stack, i. e. the ciphering required for data protection and the Robust Header Compression (ROHC) scheme employed to improve the utiliza-tion of radio link bandwidths. In particular, software and hardware archi-tectures for the time-critical algorithms are proposed, targeting an opti-mization of processing speed and energy consumption.