Date of Award

2013

Degree Type

Report

Degree Name

Master of Science (MS)

Department

Electrical and Computer Engineering

First Advisor

Dr. Jacob Gunther

Abstract

The project presented in this report is for combating the narrowband interference present in the downlink data of Dynamic Ionosphere Cubesat Experiment (DICE) satellites. The interference prevents the Phase Locked Loop (PLL) and timing synchronization loops from performing efficiently and the data is not demodulated properly. The samples are corrupted and correct decisions about the signal constellation cannot be made. Here, blind equalization techniques are used to tackle this problem. In this thesis, Constant Modulus Algorithm (CMA) and Multi-Modulus Algorithm (MMA) algorithms are extended to offset- Quadrature Phase-Shift Keying (QPSK) modulation and then implemented. When applied to simulated and real data from DICE satellites, CMA and MMA perform similarly if no phase offset is present. However, the CMA algorithm requires an external PLL in presence of a phase offset. MMA, however, performs similar or better than CMA without any need for an external PLL.

11-27-2013