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.