ABSTRACT
With the further development ofva GNSS (Global Navigation Satellite System) system, owing to provide all weather and continuous precise position, velocity and time information, the GNSS system become the significant symbol of the navigation technology (Xie 2011). However, there is some limitation in satellite navigation technology, such as the environment and weather conditions, these factors can affect position precision easily. For instance, in GPS system, only knowing at least 4 satellite’s location information, the receiver can obtain a user’s position. If the receiver affected by the non-artificial factors such as extreme environment or bad weather, the satellites which can be acquired will be only 3, even less, the receiver cannot determine the user’s location. So, using the barometric altimeter to obtain the height, which is receiver located, the objective of navigation can be achieved.
