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signal in digital form come much closer to the realization of the limit in Shannon‟s equation (1)

han the transmission of signals in analog form [9]. For these reason, digital BPSK is used in this

thesis as a control in order to measure the performance of SESS, which is based off of a direct

sequence spreading technique with a digital BPSK modulation.

1.2 Motivation and Scope of Research

This thesis research is the extended work of the self-encoded spread spectrum (SESS)

which is first proposed in [11]. Since their existence, spread spectrum techniques have used

some variation of pseudo-noise (PN) or predetermined codes to achieve spreading. SESS

eliminates this need by using spreading codes generated by the transmitted signal, thus also

eliminating the need to synchronize PN codes between the transmitter and receiver. This makes

the channel more secure, because PN codes both at the transmitter and receiver can be

deterministic.

SESS system with iterative detector has been shown to have a 3 db performance gain

over BPSK modulation in an Additive White Gaussian Noise (AWGN) channel. In a Rayleigh

fading channel, it achieves a performance gain of 15 db with just the iterative detector and even

greater when other methods are applied additionally increase the performance.

To facilitate future improvements SESS and its use for security in hostile environments it

must be studied in jamming channels. Jamming in a communication channel makes the

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