  In this paper, we propose a practical implementation of the Dynamic Decode
and Forward (DDF) protocol based on rateless codes and HARQ. We define the
macro diversity order of a transmission from several intermittent sources to a
single destination. Considering finite symbol alphabet used by the different
sources, upper bounds on the achievable macro diversity order are derived. We
analyse the diversity behavior of several relaying schemes for the DDF
protocol, and we propose the Patching technique to increase both the macro and
the micro diversity orders. The coverage gain for the open-loop transmission
case and the spectral efficiency gain for the closed loop transmission case are
illustrated by simulation results.
