The impact of GNSS spatial signal processing on position and time measurements

One of the main research directions in global navigational satellite systems is increasing the intentional interferences resistance of modern navigation receiving equipment. The most effective method is supposed to be the use of spatial filtering techniques on the basis of adaptive antenna arrays (AAA). However, antenna array can bring about additional errors in the navigation and make it impossible to use it for applications requiring accurate positioning and time synchronization. We experimentally compared navigation solutions obtained based on signals from a single antenna and from the output of AAA. The results showed that the use of AAA as the part of navigation receiver might delay 1 pps (pulse per second) signal arrival on the value proportional to the summarized group delay in the digital signal processing block of AAA. Experimental results also showed that AAA could bring error to positioning of the receiver. A few methods were outlined to decrease the influence of AAA on navigation solution.