Hildebrand, Kurt

Contact Information

Phone: (909)528-3558

Prefered E-mail: kurthildebrand@gmail.com

School E-mail: kurt.hildebrand@wallawalla.edu

PSK 31 Demodulation

Fall, 2012

• Partner Michael von Pohle

Abstract

The goal of this project was to learn more about Phase Shift Keying and to Signals and Systems in general. Since guessing the carrier frequency is slightly inaccurate a PID feedback and control system was used to correct the phase of the received signals. Despite demodulating my own signals created in MATLAB, my script does not work on the signal provided to us by Dr. Frohne and the sample signal on Wikipedia. One problem lies in the scripts inability to remove noise.

Introduction

PSK31 was developed by Peter Martinez (G3PLX) in 1998. PSK31 varies in amplitude and phase, but not frequency. This is extremely useful in amateur radio. When there is constant phase,

it is considered to be a 'one', when the phase shifts, it is a 'zero'.

Matlab Script

Matlab Plots

These are the plots

Conclusion

The end.