Published in Ansari, A., & Viswanathan, R. (1992). Application of expectation-maximizing algorithm to the detection of direct-sequence signal in pulsed noise jamming. Conference Record: IEEE Military Communications Conference, 1992 (MILCOM '92), 'Communications - Fusing Command, Control and Intelligence', v.3, 811-815. doi: 10.1109/MILCOM.1992.243994 ©1992 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder.


We consider the detection of direct-sequence spread spectrum signal received in pulsed noise jamming enviromment. The Expectation- Maximization Algorithm is used to estimate the unknown jammer parameters and hence obtain a decision on the binary signal based on the estimated IikeIihood functions. The probability of eerror performance of the algorithm is simulated for a repeat code and a (7,4) block code. Simulation results show that at low signal to thermal noise ratio and high jammer power, the EM detector performs significantly better than the hard limiter and somewhat better than the soft limiter. Also, at low SNR, there is little degradauon as compared to the maximum-likelihood detector with true jammer parameters. At high SNR, the soft limiter outperforms the EM detector.