Some 70 Trimpi events were observed on all five elements during a single night in July. For more extreme models, the dominance of geometry or diffraction can usually be established in individual cases which then allows simple scaling procedures to be used in scattering inversion. This inversion process has some validity for small LIEs of other shapes of simple form. For this model, and for single mode propagation, an inversion process is derived here for the full range of LIE and path dimensions, ranging from those for which the receiver is in the diffraction far field to those in which “geometric optics” dominate. Owing to its transform properties, the simplest model to use for scattering inversion is the Gaussian LIE distribution. With five elements, tests of the assumed model can be made as well. Although such a five-element array is inadequate for imaging of lightning-induced ionisation enhancements (LIEs) by VLF holography, or inverse scattering, estimates of LIE size and location can be made if the shape and form of the LIE can be guessed or assumed, with even fewer elements. A 600-km array of five Trimpi receivers (“elements”) has been set up in New Zealand broadside to the VLF (22.3 kHz) transmitter, NWC, some 6000 km west, with element separations varying from 8 km to 550 km.
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