A Model to Evaluate Jammer Influences on Ranging Measurements

Recently, number of intentional jamming has increased significantly. If GNSS jammers are activated, user receivers can be largely influenced due to the vulnerable characteristic of the GNSS (Global Navigation Satellite System) signal. When the reception power of the jamming signal and that of the navigation signal are similar, the C/A (Coarse Acquisition) chip delay error can occur in the delay locked loop. To evaluate the jamming effect, a new measurement model is formulated based on previous research works. The new model explains how the jamming to signal ratio affects the ranging measurement accuracy and other parameters. To evaluate the validity of the newly formulated model, the experiment results of the previous research works under actual jamming environment are utilized. By evaluating the consistency of the carrier-to-noise ratio (C/N0) and the position error with the actual jamming environment, the validity of the newly formulated model is verified.