Hi,
I am trying to simulate a temperature sensing application on TOSSIM using
the lossy radio model. I want to simulate a message loss probability of x.
As I understand, the lossy model is simulated using bit error probability.
In order to achieve the above said loss rate, following is what I am
planning to do. Could someone please confirm if this makes logical sense?
Assuming the message size = 30 bytes = 30 * 8 = 240 bits. Let the bit
error probability (specified in the loss model file on the command line of
tossim) for any sender receiver pair be y. Then the message loss
probability x and bit error probability y are related as follows:
x = 1 - (1 - y)^240
For simplicity, ignoring collisions and hidden terminal problem, a message
is lost if the CRC does not match the CRC in the message. Also, assuming
that any bit error leads to a CRC mismatch, 1 - y is the probability that
a bit is transmitted properly. The probability that all bits in the
message are transmitted properly without error is (1 - y)^240. The
probability that a message is received properly is equal to the
probability that all bits are transmitted properly i.e.
1 - x = (1 - y)^240
or equivalently: x = 1 - (1 - y)^240
Please point out flaw in the above argument.
Thanks and Regards
Pavan Edara
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