Analysis of a modified Polar Sigma-Delta transmitter architecture for multi-radio applications

Polar sigma delta architecture has been previously proposed as an universal architecture able to offer multi-radio transmission in a mobile system. Furthermore, it has been validated for mobile WiMax, a very exigent communication standard in terms of envelope magnitude range and channel bandwidth. This paper briefly describes polar sigma delta architecture and proposes some improvements to it, particularly the digital mixing instead of analog mixing. Simulations of the enhanced architecture have been carried out using agilent advanced design system. Results are analyzed and new architecture advantages and drawbacks are pointed out.