想問一題網路和機率的問題
M(M >> 1)bits of user data are to be transmitted in the form of fixed length
frames with D bits of data and K bits of overhead each. A channel with bit
error probability b is used. A frame is considered to be corrupted if one or
more of the consitituent bits are in error. A corrupted frame is to be
retransmitted until it's successfully received. Assume the total number of
transmittion attempts for for sending frame can be characterized by a
geometric destribution
a. what is the expected number of bits transmitted?
b. what is the optimal frame size if b=0
c. what is the optimal frame size if K=0
d. what is the optimal frame size in general(assuming b(D+K)<< 0)
a. (D+K)(1-b)^(D+K)
b. D+K
c. D(1-b)^D
d.不會
因為題目看不太懂,所以想請問一下不知道對不對..@@
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