Thermal Vibration's Impacts on a GPS Receiver in a Mobile Phone with Limited PCB Area and Placement

摘要

When designing a GNSS receiver for a mobile phone, it iscrucial to consider the thermal impacts on the GNSS localclock. The local clock – usually a crystal oscillator (XO)or a temperature compensated crystal oscillator (TCXO)is sensitive to temperature changes. Components aresuqeezed on a limited space (printed circuit board (PCB))of a smart phone. Each electronic component is a heatsource. Thus the local clock is easily impacted by thethermal vibrations from the sourrounded components. Thethermal vibrations create excessive dynamic stress on theGNSS receiver and cause performance degradations inpositioning. This paper illustrates the problem; verifiesthe correlation between the impaired clock signals and theGNSS receiver performance; proposes both hardware andsoftware solutions, and demonstrates the effectiveness ofthe solutions by the final positioning performance of theGNSS receiver in a compact smart phone.