  Space plasma studies frequently use in situ magnetic field measurements taken
from many spacecraft simultaneously. A useful data product of these
measurements is the reconstructed magnetic field in a volume near the
spacecraft observatory. We compare a standard method of computing the magnetic
field at arbitrary spatial points, the Curlometer, to two novel approaches: a
Radial Basis Function interpolation and a time-dependent 2D inverse distance
weighted interpolation scheme called Timesync. These three methods, which only
require in situ measurements of the magnetic fields and bulk plasma velocities
at a sparse set of spatial points, are implemented on synthetic data drawn from
a time-evolving numerical simulation of plasma turbulence. We compare both the
topology of the reconstructed field to the ground truth of the simulation and
the statistics of the fluctuations found in the reconstructed field to those
from the simulated turbulence. We conclude that the Radial Basis Function and
Timesync methods outperform the Curlometer in both the topological and
statistical comparisons.
