An anechoic chamber free approach to GNSS antenna array gain and phase calibration is proposed and evaluated for a stationary array. The constellation change of the satellites was used to measure the variations in gain and phase over two twelve hour periods. The results was compared to an array calibrated using traditional methods in an anechoic chamber. It is shown that the method agrees well with the traditional method. Care was taken to make sure interference and multipath levels were low.The processing is performed using acquisition and tracking loop software implemented in Matlab. The IF data is recorded with a multi front end recording system.