Projects:2016s2-216 GPS Receiver Location and Atmosphere Characterisation
Team members
Man Kit Law
Menghang Jiang
Supervisors
Michael Liebelt
Matthew Trinkle
Project Description
We recently built an FPGA GPS receiver which has been incorporated into a satellite and is due to be launched later in the year.
This receiver sends back raw GPS signal measurements from which it should be possible to determine the position of the satellite as well as properties of the atmosphere based on the signal delays. We have a second copy of the GPS that is almost identical to the one in the satellite and can be used for experimentation.
The main aims of this project are to use the raw GPS measurements obtained from the GPS receiver module (codephase and carrier phase) to determine the position of the GPS receiver and the delay of the GPS signals through the atmosphere. Initially we will be using the measurements from the duplicate receiver on earth. But hopefully we will be able to use the data from the actual satellite early next year.
Objectives
The project’s objectives are listed below.
• Raspberry Pi board
It is used to transmit data through I2C communication between an identical MASP replica board and on-ground PC for testing purpose. The operation between MASP replica and Raspberry Pi board can verify the actual MASP can operate correctly and give us good results before it can be used. Project member Eric Jiang is responsible for this objective.
• Modified Matlab code
Based on the signal sent from MASP replica to PC. The modified Matlab code in PC can do the satellite and receiver position calculations and hence find the position solution. It verifies the signal sent from MASP is correct and MASP can rely on its own signal to find out the position solution in space and hence send back to earth.
Key Tasks
Since SUSat has not been tested yet, the project team is not able to do any experiments using SUSat. In order to test if the MASP is worked or not, one of the supervisors Matthew Trinkle gave us a MASP replica which is identical to the MASP board that in space with exactly same functions.
There are three key tasks in this project – “Raspberry Pi board implementation”, “Matlab code modification” and “GPS receiver location determination”. The above two tasks were going to process at the same time. Finally, the task “GPS Receiver location determination” was done by the whole group.