Design And Implementation Of Energy Efficient GPS Sensing Platform

Location is one of the most important services in the mobile computing, wherethe GPS receiver is an important tool which is widely used in the outdoorenvironment. However, traditional solution for GPS location must consume a lot ofenergy for acquiring the signal from the satellites. It is a big challenge for themobile application, because the hardware of the mobile application always use aportable battery whose energy is limited and difficult to be recharged. To solve thisproblem, the paper proposes a novel energy efficient GPS sensing platform.The platform splits the process of the GPS location into two parts: acquiringGPS baseband signal in the GPS collection node and computing the locationcoordinate in the cloud server. In this way, it can transfer the energy consumption ofthe computation from the GPS collection node to the cloud server and thus reducethe workload of the GPS collection node. Besides, the computation process of GPSlocation in the server can use the online resource, such as satellite ephemeris andgeographical database. Thus, the platform can only need two millisecond GPSbaseband signal data and a coarse time stamp, and further reduces the energyconsumption.The whole platform contains three layers. The bottom layer is the GPScollection node. Its function is to acquire the environment parameters including GPSbaseband signal and coarse time stamp, etc. The middle layer is the mobile smartterminal. It acts as a bridge between the GPS collection node and cloud server andmeanwhile provide a friendly. The top layer is the cloud server, and it computes thelocation of the GPS collection node based on the online resources and the data fromthe lower layers.According to the experiments, the novel platform can successfully acquire4satellites to satisfy the need of GPS location by only2milliseconds of GPSbaseband signal and one order of magnitude lower energy consumption energyconsumption compared to more than30seconds of heavy signal receiving and1J ofenergy consumption in the traditional GPS sensing solution.