  The Van Atta retro-reflector can be envisioned as a self-phasing antenna
array; a phase gradient, naturally induced by an external incident wave, is
inverted so the device re-radiates back towards the incident direction. This
Letter demonstrates how to re-direct the re-radiated beam through passive
alteration of this phase gradient. For this purpose, crosspropagating isolation
is required between the incident and reradiated signal paths. To this end,
polarization duplexing can be used to achieve this isolation with a passive and
reciprocal structure. To provide further demonstration, a 4-element redirective
array is designed and fabricated to offset its re-radiated beam by -15{\deg}
from incidence. Performance is then verified using fullwave electromagnetic
simulation and experimental radiation pattern measurements. It is found that
the -15{\deg} angular offset is effectively retained over a wide range of
incidence angles.
