Transmitter modulation performance analysis

Abstract

Satellites have been widely developed for education, earth observation, constellation operation and etc. Satellite tracking and orbit determination are essential elements of most satellite missions. The knowledge of the spacecraft position at any time is a requirement for communication and planning.

The objectives of this project are divided into two main parts. The first objective of this project is to design the software-defined radio to generate a sweeping carrier at the receiver band to track the satellite. The first objectives ensure both the satellite transmitter/receiver system and the ground station system are capable of handling the Doppler shift in frequency by locking the satellite transmit (carrier) frequency with the ground station center frequency. The second objectives are to generate a 4 kbps BPSK on 16 kHz subcarrier at the last generated frequency of the sweeping carrier. Lastly a simulation tool is implemented using LabVIEW to allow user to visualize and analyze the modulation performance of the UUT. This project took advantage of the high bandwidth of the PXI bus to provide new and more flexible testing scenarios. It is now possible to generate complex waveforms simulating actual operations or network traffic just using software on a suitable hardware platform. vi Processing power is increasing every day, newer and more innovative use of this performance is only limited by our imagination.