This requires GNSS receivers to simultaneously balance the competing requirements of high sensitivity to weak signals and also aggressively filtering out of signals outside the specified range. Moreover, the signals are also being transmitted on the same frequency and the receivers on Earth need to not only detect the signal but they also need to recover the coded information in order to process the data. This is important as GNSS satellites orbit the Earth at an altitude of approximately 20,000 km with a transmission power of between 20-240W this corresponds to measured received signal strength on the surface of the Earth of around -130dBm (or around 0.05% of the strength of a cell phone signal). The critical criteria used to assess the performance of receivers includes spacial accuracy, sensitivity, and integrity. The strategic and economic importance of the system has also motivated other countries and alliances to develop their own, alternative systems, such as Galileo, GlobalвЂ™naya Navigatsionnaya Sputnikovaya Sistema (GLONASS) and BeiDou. The impact, utility, and benefit of GPS, has spanned everything from personal navigation via cell phones, to air plane navigation, to construction surveys, and logistic. The original, and most well known, GNSS system is the Global Positioning System, which is owned and operated by the United States government. While originally developed for defense purposes, the utility of this technology has now seen it deployed across a variety of consumer, commercial, and industrial products.

This information typically consists of various timing and orbital parameters, from which a receiver can infer their position with respect to the orbiting satellites. Receivers typically use multilateration algorithms to infer their location relative to the orbiting satellites. Global Navigation Satellite Systems (GNSS) refers to systems that use satellites in orbit to assist earth bound devices in determining navigation information.

Satellite receiver radio