A Mobile Platform Using Software Defined Radios For Wireless Communication Systems Experimentation

A distinctive feature of wireless communication systems is implied by the fact that there is no physical connection between the transmitter and its corresponding receiver, which enables user mobility. However, experimenting with wireless communication systems is mostly done in the lab, where transmitters and receivers are setup on benches, in stationary settings. This prevents students from experiencing fading and other propagation effects associated with mobile wireless channels. This paper describes a mobile platform for wireless communication experimentation that enables students to run experiments beyond the confines of a traditional lab, in realistic settings that cover indoor and outdoor scenarios with both fixed and mobile propagation characteristics. The platform presented consists of a Universal Software Radio Peripheral (USRP) from National Instruments to implement the transmitter, an affordable RTL-SDR USB dongle to implement the receiver, a laptop computer used to program the SDR boards, and equipment for visualizing radio signal characteristics such as a portable spectrum analyzer or oscilloscope. This choice results in a moderate overall cost for the radio hardware required by the platform, which can be easily programmed using open source software such as GNU Radio as well as software packages like Matlab or LabView. For experimentation in wireless scenarios with low mobility (both indoors and outdoors, corresponding to walking speeds) the transmitter and receiver may be placed on push carts, while for higher mobility they may be placed on university owned golf carts moving at faster speeds on the designated campus routes. Furthermore, mobile transmitters and receivers may also be placed in cars driving on the campus streets and through the university parking lots/garages to enable experiments simulating vehicle to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications