How to simulate the success of an RF packet transfer knowing the packet size and BER

Question

I'm trying to simulate a data protocol running over a 5 Mbps RF link. The datasheet for the RF chip gives a logarithmic BER vs SNR plot (BER := bit error rate; SNR := signal to noise ratio), but to simplify I am choosing to fix the BER to the same value that many of the RF characteristics are measured: BER = 10^-4.

How do I determine the instantaneous success of a packet transfer of size N bits (N := { 36000, 18000, 9000, 4500})?

I'm not looking for the probability of success (but that may be needed as an interim calculation). I need to be able to make a boolean decision about each packet as the simulation time ticks by. I also have a random number generator available as input and can keep a packet transfer history if necessary. I'm using the SimPy package for even simulation.

Answer 1

I may be misunderstanding your question. You just want to know immediately if a packet has a bit error? If not, could you clarify your question to more clearly state what you want to find?

BER is essentially the probability of a bit error. 1 in 10,000 bits has an error. So, if you do (1-BER)^N you'll get the probability that packet succeeded. Then, for your simulation to determine if any given packet was successful get a number between 0 and 1 from your PRNG. If it's less than your (1-BER)^N, that packet was successful. Otherwise that packet contained a bit error.