A comprehensive energy model and energy-quality evaluation of wireless transceiver front-ends

Abstract

As CMOS technology scales down, digital supply voltage and digital power consumption goes down. However due to dynamic range limitations, power supply and power consumption of the RF front-ends and analog sections do not scale in the same fashion. In fact, in scaled systems, the RF section of a wireless transceiver consumes more energy than the digital part. For better understanding of the design trade offs, we first develop an accurate and comprehensive energy model for the analog front-end of wireless transceivers. Next, we evaluate a single user point-to-point wireless data communication system and a multi-user CDMA based system with respect to RF front end energy consumption and communication quality. We demonstrate the effect of occupied signal bandwidth, peak-to-average ratio (PAR), symbol rate, constellation size, and pulse-shaping roll-off factor on single user system, and the effect of number of users and multiple access interference (MAI) on CDMA based multi-user system. For a given quality specification, we show how the energy consumption can be reduced by adjusting one or more of these parameters.