M2RX Mobile Multicast Receiver - Advanced Signal Processing Techniques

The use of deep submicron CMOS technology for analog/RF circuits is slowly becoming state-of-the-art in wireless transceiver design for frequencies up to 5 GHz, if low-cost mass market applications are targeted. As CMOS is usually not optimized for analog performance and additionally with decreasing feature size the supply voltage also decreases, the design of high performance analog/RF building blocks is an extremely challenging task. A common means to relax the target specifications for the analog/RF circuitry is the extensive use of digital signal processing for correction of distortions and imperfections introduced in the analog circuitry. With using CMOS, this computing power comes at very low cost. Advanced digital signal processing methods are investigated, which enable a blind or semi-blind correction of these RF impairments which are especially crucial in OFDM-based systems. These are mainly phase noise, frequency offset, frequency drift, and I/Q mismatch. For I/Q mismatch the main focus will be put on its frequency dependence, due to the wide bandwidth and the broad range of different frequency bands to be supported by the M²RX system.