  An index coding scheme in which the source (transmitter) transmits binary
symbols over a wireless fading channel is considered. Index codes with the
transmitter using minimum number of transmissions are known as optimal index
codes. Different optimal index codes give different performances in terms of
probability of error in a fading environment and this also varies from receiver
to receiver. In this paper we deal with optimal index codes which minimizes the
maximum probability of error among all the receivers. We identify a criterion
for optimal index codes that minimizes the maximum probability of error among
all the receivers. For a special class of index coding problems, we give an
algorithm to identify optimal index codes which minimize the maximum error
probability. We illustrate our techniques and claims with simulation results
leading to conclude that a careful choice among the optimal index codes will
give a considerable gain in fading channels.
