  Motivated by the link between Anderson localisation on high-dimensional
graphs and many-body localisation, we study the effect of periodic driving on
Anderson localisation on random trees. The time dependence is eliminated in
favour of an extra dimension, resulting in an extended graph wherein the
disorder is correlated along the new dimension. The extra dimension increases
the number of paths between any two sites and allows for interference between
their amplitudes. We study the localisation problem within the forward
scattering approximation (FSA) which we adapt to this extended graph. At low
frequency, this favours delocalisation as the availability of a large number of
extra paths dominates. By contrast, at high frequency, it stabilises
localisation compared to the static system. These lead to a regime of
re-entrant localisation in the phase diagram. Analysing the statistics of path
amplitudes within the FSA, we provide a detailed theoretical picture of the
physical mechanisms governing the phase diagram.
