Sequential Block Orthogonal Signaling with Two Noiseless Decision Feedbacks

A sequential block orthogonal signaling scheme with both an intermittent and a final decision feedback is developed. The reliability function for this communication technique is shown to be bounded below by
\alpha_{max} \bar{C} - R
, for
0 \leq R < \bar{C}
where α
max
is one-half of the ratio of the maximum transmitted signal average power P
pmax
to the expected transmitted signal average power
\bar{P}
. The transmitter power advantage of this feedback scheme in a nonasymptotic operational mode is also presented.