The growth of innovative positioningrelated services and applications within the wireless mass-market, and the green light for the

The geographical location of a wireless device is acquiring a significant importance under the boost of innovative applications in the wireless market, and under the research activities related to the development of a new generation of Global Navigation Satellite Systems (GNSS). In the US a new phase of the Global Positioning System is foreseen, and Europe has decided to proceed with the Galileo program. In addition, different government institutions worldwide are working toward the definition of navigation plans, and regulations will set as mandatory the location identification of mobile users in emergency situations (US E‐911 law and the European E‐112 directive). Considering all the navigation/positioning systems and techniques that will be available in the near future, it is clear that a central role will be played by the user handset; in fact, if navigation signals from different sources will be available, the unique possibility to obtain the best navigation performance from the user perspective will be the employment of enhanced receivers able to fuse different data. With this aim, this paper presents the design of an innovative navigation receiver based on Software Defined Radio (SDR) technology. The reconfigurability and flexibility issues are guaranteed by the use of reprogrammable high‐speed hardware (FPGA—Field Programmable Gate Array and DSP—Digital Signal Processor) and thus a deep integration at the raw signal level between GPS and the future Galileo has been obtained. The interoperability issue among different systems is then solved at the receiver level. This paper discusses the implementation of a baseline architecture of a reconfigurable GNSS receiver over a FPGA + DSP prototype platform. The receiver is able to deal with different input Signals‐In‐Space (SIS), and can operate with present GPS ranging signals or with the future Galileo SIS. Copyright © 2002 John Wiley & Sons, Ltd.