A SUPL-based A-GPS simulator support for indoor positioning

Conventional Global Positioning System (GPS) receivers are designed to operate in open-sky environments and have difficulty dealing with signal blockage from buildings and foliage which deteriorates their performance in urban canyons, indoors, and underground. In recent years, engineers have developed receivers that perform satisfactorily even with severely attenuated signals by providing external assistance such as satellite orbit parameters, reference time and coarse locations. This approach known as Assisted GPS significantly facilitates the acquisition of satellite signals, and relieves the receiver from the data demodulation tasks. While it is common to use GPS simulators for testing receivers only high-end simulators support testing of AGPS capability as it involves additional assistance generation and delivery to target devices in addition to GPS signal or measurement generation. Typically such simulators are not affordable for many academic institutions. This paper describes an affordable approach to augment conventional GPS simulators with A-GPS testing support.