Test of Crowdsourced Smartphones Measurements to Detect GNSS Spoofing and Other Disruptions

GNSS spoofing is a growing concern due to the increasing use of GNSS in safety and economically important applications. The widespread use of GNSS in these tasks means that GNSS needs to be protected from spoofing in many location. Even with the most basic task of GNSS spoof detection, it is generally difficult and costly to have a rapid and widespread response. An attractive way of addressing the challenge is to harness the most widespread and lowest cost GNSS receivers, those found in smartphones, to help with spoof detection. Further enhancing this potential are the raw GNSS measurements enabled by the latest versions of Android (7.0 and above). The capability and ubiquity of these GNSS receivers along with the connectivity and alternative navigation sources found in smartphone makes a crowdsourced network both powerful and reasonable. This paper examines the potential of these crowdsourced, networked smartphone measurements for spoof detection. Specifically, it focuses on tests of the crowdsourced detection concept using different smartphone measurements and multiple smartphones. It examines several available measurements: 1) position, 2) acceleration (from GNSS and accelerometer), 3) automatic gain control (AGC) and carrier to noise (C/No) levels and 4) pseudo ranges. These are examined on both a standalone and a networked, cross receiver basis. These are examined using measurements taken from laboratory and field tests, including an on air spoofing test.