I have a similar reverse, also with windows in the turrets on a Licinius II campgate.
Licinius II 318-319AD
Laureate, draped, cuirassed bust, LICINIVS IVN NOB C
Campgate, 6 layers, 3 turrets with windows, closed, panelled doors, P in left,
R in right, VIRTV-S AVGG
RS in exe
RIC VII Rome 182, 3.3g, 19mm
Tjaart