The idea of a software receiver is to replace the data processing implemented in hardware with software and to sample the analog input signal as close to the antenna as possible. Thus, the hardware is reduced to the minimum (antenna and analog to digital converters) while all the signal processing is done in software. As current mobile devices (such as personal digital assistants and smartphones) include more and more computing power and system features it becomes possible to integrate a complete GNSS receiver with very few external components.