Integration of Galileo and UMTS Services Using a Software Radio Based Receiver

A preliminary study is presented on a Software Defined Radio (SDR) receiver with the capability of receiving both the position information and the cellular services. In these last years, a great attention in wireless communication is devoted at integrating different standards into the same device in order to make a reconfigurable wireless terminal. In particular one of the most important topic is the integration of the positioning service into a wireless device. This solution will be proposed, for example, in the next generation wireless terminal like UMTS. In order to realize this target it is necessary to find out a good solution that allows this possibility with a certain level of flexibility and modularity. The proposed solution is well known as Software Defined Radio. This technology builds flexible radio systems, multiservice and multistandard reconfigurable and programmable by software. Moreover it has to provide a multiband reception where each frequency band corresponds to a different communication service. In this work the possibility to provide the UMTS standard by positioning services employing GNSS services is investigated. The proposed solution is based on the use of SDR techniques to provide the integration between the different signals: UMTS and GNSS. Both standards use CDMA transmissions. Our attention is focused in the downlink UMTS channel. The presence of the UMTS signal is a jamming source for the Galileo signal and it can deteriorate the tracking and first acquisition modules performances. In this work it is shown that the chosen frequency overlapping does not affect the position estimation performances. Theoretical and simulation results show that the solution adopted in this paper do not affect normal synchronization performances of the Galileo signal and allow to build a multimode receiver.