Parameter Estimation Using a Triad of Electrically Long Dipole Despite Data Model Mismatch

Most dipole-antenna signal processing algorithms have focused on “short dipole” whose physical length (
$L$
) is under (
$1/10$
) of a wavelength (
$\lambda$
). Recent works now handle “long dipoles” of an electrical length
$L/\lambda \in [0.1, 1]$
. This article advances an algorithmic paradigm that uses short-dipole algorithm on long-dipole data. By studying the mismatched Cramér–Rao bound, we find that applying short-dipole algorithm to a long-dipole data model may yield parameters' estimates that are not far from their true values especially when
$L/\lambda$
is small. This phenomenon motivates a two-step algorithm where we apply short-dipole algorithm to get parameters' coarse estimates, which are then fine-tuned by an iterative algorithm. Our algorithm maximally retains the merits of the existing short-dipole algorithms while processing the signals received by a long dipole triad. Monte Carlo simulations verify the effectiveness of the proposed paradigm.