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Chapter 8 Conclusions / Future Work

Self-Encode Spread Spectrum eliminates the need to synchronize m-sequences between

transmitter and receiver, because it uses spreading codes generated by the transmitted signal.

This also eliminates the security flaws associated with m-sequences, thus making the channel

more secure. This paper discussed the performance of SESS system with an iterative detector in

AWGN and Rayleigh fading channels. Introduced was the worst-case pulsed-noise jamming to a

SESS, as well as, a potential solution for the jamming. The performance of the SESS system

with the iterative detector outperformed the standard DSSS system by 6 db at a BER of 10-3.

This performance is great, but fails to come close to the performance of improvement seen in the

Rayleigh fading channel. In an attempt to increase the performance of the worst-case jamming,

modification of the SESS system was made. By making decisions based on the chips instead of

the bit, the worst case performance can be increased dramatically. However, by looking into the

performance of chip based decisions in noise and fading channels, then introducing noise into the

jamming simulation made chip decisions less desirable. When taking physical limitations of

jamming systems into consideration, the chip decision based system performance suffers more,

but under absolute worst-case jamming conditions it could still offer improvement over the bit

based decisions. Future work needs to be done to explain why the performance of the iterative

detector in jamming differs from that in a fading channel. More work is also needed to improve

the worst-case jamming in SESS with iterative detector by a defeating jamming by implementing

an advanced form chip decision or other method.

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