  The future wireless networks envision ultra-reliable communication with
efficient use of the limited wireless channel resources. Closed-loop repetition
protocols where retransmission of a packet is enabled using a feedback channel
has been adopted since early days of wireless telecommunication. Protocols such
as automatic repeat request (ARQ) are used in today's wireless technologies as
a mean to provide the link with reduced rate of packet outage and increased
average throughput. The performance of such protocols is strongly dependent to
the feedback channel reliability. This paper studies the problem of feedback
error and proposes a new method of acknowledging packet delivery for
retransmission protocols in unreliable feedback channel conditions. The
proposed method is based on backwards composite acknowledgment from multiple
packets in a retransmission protocol and provides the scheduler of the wireless
channel with additional parameters to configure ultra-reliable communication
for a user depending on channel quality. Numerical analysis are presented which
show orders of magnitude increase in reliability of the proposed method as
compared to ARQ at the cost of a small increase in average experienced delay.
