Polaris Total RadioTM, a highly integrated RF solution for GSM/GPRS and EDGE

This paper describes how the constant goal to achieve higher functionality at lower cost drives innovation in chip set architectures and accomplishments in integration in RF semiconductors. This paper will discuss a complete GSM/GPRS radio system that has been implemented by use of highly integrated circuits that exhibit levels of integration and features unparallel in the industry. A new, proven radio architecture and it´s performance will be shown including the integration of VCOs and associated loop filters, system oscillator, power management, power amplifier power control circuitry, auxiliary DACs and more. System details will be show how the elimination of IF filters is supported by the use of either zero IF (ZIF) or very low IF (VLIF) radio architectures. A comparison between ZIF and VLIF is presented. The use of a fractional N synthesizer based digital GMSK modulator and DSP based digital channel filters will be discussed. Additionally, the benefits derived by use of digital radio-to-baseband interfaces are discussed and the implications to the industry are presented.