Phase and group delay analysis for patch antenna

The phase and group delay analysis of patch antenna for global navigation satellite system (GNSS) application is presented in this paper. A four-feed circularly polarized patch antenna is modeled, and the method of how to compute the carrier phase center and group delay center is described. Based on the model and method, the carrier phase center and group delay center of the patch antenna in variation substrate thickness are analyzed mathematically. The difference between the carrier phase center and group delay center is obtained.