A coding and testing scheme is proposed for distributed
hypothesis testing over multiple-access channels (MAC).
The scheme combines hybrid coding with a MAC-version of
Borade’s unequal error protection. The resulting error exponent
recovers the previous exponents by Rahman-Wagner and by
Sreekuma-Gunduz for the special case of testing against conditional
independence, and it is optimal when the sources at
transmitters are independent under both hypotheses. In all these
special cases, without loss in performance, hybrid coding can be
replaced by separate source and channel coding.