Effects of deviations from the plane-wave assumption on EM-SVD-based wavevector reconstruction. The base case corresponds to a purely parallel-propagating ICW. The test case consists of a superposition of two ICWs: a dominant component with amplitude 0.8 propagating parallel to the background magnetic field and a secondary component with amplitude 0.2 propagating at 10° relative to the background field. (a), (b) Reconstructed wavevector magnitudes for the test and base cases, respectively. (d), (e) Corresponding angles between the reconstructed wavevector and the background magnetic field. (c), (f) Ratios of the wavevector magnitudes and propagation angles between the test and base cases.