utilizing physical layer information to improve rfid tag
utilizing physical layer information to improve rfid tag
utilizing physical layer information to improve rfid tag
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Figure 6.9. Random number distribution for <strong>tag</strong>s A and B.<br />
performance of the identification process if the random number genera<strong>to</strong>r has a prob-<br />
ability distribution function like Gaussian, Poisson etc. Fig. 6.15 shows the various<br />
PDFs used and their distribution for a Q value of 6 which gives 64 slots.<br />
Fig. 6.16 shows the identification time required for each of the above cases.<br />
We see that initially all approaches show similar identification times but when the<br />
number of <strong>tag</strong>s in the field is 100 or more, Gaussian PDF shows an <strong>improve</strong>ment over<br />
uniform PDF. The following values were used for the PDFs.<br />
Uniform : range = 1 <strong>to</strong> 2 Q<br />
Gaussian : mean = 2 Q /2, variance = 2 Q /4.<br />
Poisson : λ = 2 Q /2<br />
Rayleigh : σ = 2 Q /4<br />
Gamma : a= 2 Q /4, b = 2<br />
For every alternate round only half the number of slots are used. This round is used<br />
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