High-sensitivity cloud-offloaded instant GPS for indoor environments

Due to poor signal-strength, multi-path effects, and a lack of adequate visible satellite vehicles (SV), GPS receivers do not work indoors. This work addresses these challenges by using a mechanically steerable, high-gain directional antenna as the front-end of the GPS receiver along with a robust signal processing technique to acquire satellites in indoor environments. Our experiment on a local warehouse shows that, the system is capable of acquiring 5 or more SVs (which is a requirement for instant GPS technique [4]), whereas a Garmin device barely sees 3, and the system is capable of estimating indoor locations with 3--18 m errors when compared to the ground truth.