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Figure 19 and Figure 20 shows that chip decision does improve the worst-case scenario

by as much as 8 db over bit decision (at BER of 10-4) in a noise or fading channel with jamming.

However, just like as the worst-case jamming depends on prior knowledge of the system to

achieve the best jamming, the decision to use chip based decisions requires knowledge of the

jamming. With knowledge of the ρ, a decision could be made to switch to chip based decision to

help improve performance.

The final problem affects both systems and it is that in the simulations we assumed that

the jammer had a limited average power and unlimited peak-power. With the ρ values low, the

peak-power is affected because the voltage of the jammer is increased by 1/ . The voltage

cannot be expected to continuously increase at this rate, as there will be a physical limit to the

system and it would eventually begin to decline. It is especially bad for the chip decision, as it

has been shown that the ρ values where the chip decision becomes most valuable is at the lower


7.4 Discussion

Perhaps, using a hybrid system of both bit and chip decision could help alleviate the

problems that the bit decision system has at low duty cycles, while giving the performance of the

bit decision at higher duty cycles. More performance could potentially utilized from the chip

base decisions by adding weights to each chip decision. The way the system in the simulation

runs is it changes the chips values of -1 or 1. By adjusting the values based on the original

voltages, it could bridge the gap in performance between the chip and bit decision system. This

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