On the Swamp County Railroad system there are 6 types of train
P1 P2 F1 F2 F3 F4
They occur with the following probabilities
P1 0.10
P2 0.10
F1 0.20
F2 0.30
F3 0.15
F4 0.15
A trackside device transmits the type of train that passes.
(a) If a fixed-length code is used, how many bits need to be sent for each train?
(b) Given the probabilities above, devise a Huffman code and fill in the following table.
Symbol Code
P1
P2
F1
F2
F3
F4
(c) What is the AWCL of your answer to (b)?
(d) If 1000 trains pass, with the distribution shown, how many bits are saved by using the Huffman code instead of the fixed code from (a). Show your calculations.