There is provided a positioning system that comprises a GPS device including a GPS receiver arranged to receive GPS satellite signals from a plurality of GPS satellites and an attenuation device arranged to attenuate GPS satellite signals such that when a GPS satellite is located in a first portion of sky the GPS satellite signals received by the GPS receiver from said GPS satellite are attenuated. A storage is provided to store satellite location information for the plurality of GPS satellites over time at a location of the GPS receiver, and a controller is provided to determine location information of the GPS device based on received GPS information from the GPS device, wherein the received GPS information comprises information on signal strengths of the GPS satellite signals received by the GPS receiver. If a signal strength for a first GPS satellite is lower than a threshold signal strength at a point in time then the controller is arranged to determine that the first GPS satellite is in the first portion of the sky and determine angle information of the GPS device relative to earth's normal and/or orientation information of the GPS device in a horizontal plane using the stored satellite location information.