An investigation of quantization effects in OFDM at digital IF in high capacity digital wireless systems

OFDM (Orthogonal Frequency Division Multiplexing) modulation has been widely implemented in existing WLAN (Wireless Local Area Network) systems as well as being the modulation of choice for the emerging 4G LTE (Long Term Evolution) mobile phone data system. Quantization is a very important part of the design of such systems since much of the required complex signal processing is done in the digital domain. Quantization implemented by ADCs (analogue to digital converters) and DACs (digital to analogue converters) is a significant contributor to power consumption in battery-powered hand-held terminals and optimization of the quantization yields power savings and extended battery-life. Until now, the quantization process for OFDM systems has been poorly understood and the models used have been inadequte. This thesis introduces new methods to illuminate the OFDM quantization process and to optimize it for use in target high capacity digital wireless systems.