GPS Accuracy of the Latest C-V2X Units for V2X Applications

Vehicle-to-Everything (V2X) communication is essential for connected and autonomous vehicles (CAV) especially location sharing of the CAV. This paper analyzed the accuracy of the global positioning system (GPS) of the current generation Cellular V2X (C-V2X) units by comparing to a reference differential GPS (DGPS) system. The GPS data of an On-Board Unit (OBU) was extracted from SAE J2537 messages. Two tests were conducted for comparison. In the first test, the OBU in a test vehicle was stationary and GPS accuracy for three commercial GPS antennas was measured against the reference DGPS system using a known geodetic location. The result shows that the current C-V2X OBU has a Circular Error of Probability 50% (CEP-50) of 1.08m error in average position compared to the DGPS. In the second test, the OBU in the test vehicle was driven at 19 m/s through the roadway. It was found that the C-V2X system tracked within a root means square error (RSME) of 0.278 m in distance and 0.8 m/s in speed.