Development of a high data rate VHF and UHF satellite ground station

• Main Author: Ye, Chuang
• Other Authors: Low Kay Soon
• Format: Theses and Dissertations
• Language: English
• Published: 2015
• Subjects: DRNTU::Engineering
• Online Access: http://hdl.handle.net/10356/64781
• Institution: Nanyang Technological University

Since April 2010, NTU has started the development of VELOX-1. It is the first Singapore nano-satellite to operate in Low Earth's Orbit (LEO) and also the First nano-satellite mission in South East Asia. In this project, we aim to improve the existing NTU VHF/UHF satellite ground station which has been developed for VELOX-PII operation to support the upcoming VELOX-I mission with high speed downlink capability. The scope of this project consists of the hardware and software architecture of the ground station for VELOXI operation, the communication link budget calculation, high speed downlink test, range test in far-field environment and the ground station operation. In this project, the hardware and software architectures have been improved after studying the satellite ground station technology and VELOX-I communication system. To quantify the expected performance of the improved ground station, the link budget calculation is performed. The results show that at a default bit rate of 1200bps, the uplink has a minimum margin of 9. 72dB while the downlink margin is 15 .46dB at 10 degrees elevation. Thus stable communication during a ground pass can be achieved. From 1200bps to 9600bps, the average downlink reliability drops from 0.95 to 0.76, while the average utility increases from 1.15 to 6.03. Therefore the station has the capability to receive frames at high speed with higher efficiency. In the range test, the modified system is capable of receiving data with Et!No as low as 4.52dB. The results from this project provide us high confidence in communicating with VELOX-I after it has been launched. In summary, this NTU ground station is fully operational in the desired VHF and UHF bands with high speed downlink capability. It will be used for the command and control of the VELOX-I in 2014.