Low Noise Amplifier (LNA) Linearity Impacts to Close Proximity Co-Located GPS L1 Receivers

A commercial low-cost global positioning system (GPS) L1 (Fc = 1575.42 MHz) receiver in close physical proximity to a 2G/3G/4G compliant cellular handset transceiver front end module (FEM) is analyzed for performance impacts related to various forms of electromagnetic (EM) interference. A description of how the GPS L1 receiver works is presented. GPS L1 receiver link budgets, simulation and measured receiver data, and spurious analysis tools are used to present typical performance along with analysis and summary of how interference impacts GPS L1 receiver key performance parameters (KPPs). Means and methods to ameliorate the effects and impacts of interference to the GPS L1 receiver are proposed. Emphasis is placed on the GPS L1 receiver’s low noise amplifier (LNA) key performance parameters (KPPs) and how the LNA’s third order intercept (IP3, or TOI) rating can be used to predict improved immunity to interference effects, including interference caused by close proximity