Pseudo Range Estimation Model Based on Received GPS Signal Power in Many Skyscrapers Environments

In recent years, GPS (Global Positioning System) [1] has been widely used and introduced in various systems. However, in environments where skyscrapers stand side by side such as metropolitan Tokyo, it is difficult to receive GPS signals from GPS satellites directly. So, many reflected GPS signals are received. They might make calculated distance errors longer due to their longer pseudo ranges than those of direct signals. Elevation mask is an existing technology to improve calculated distance error by not using the reflected signals as possible. However, in many skyscrapers environments, the number of receivable GPS signals might be less than 4 by larger elevation mask. Therefore, it is likely to use the pseudo ranges of the reflected signals positively which is not used by elevation mask and we proposed a pseudo range estimation model that can estimate the number of reflections and the incident angles of the received GPS signals from their received power. By using our proposed estimation model that is possible to approximate the pseudo range of the reflected signal to that of the direct signal. In this paper, we show the improvement the calculated distance error of the proposed method by simulation.