High Speed High Signal-to-Noise Ratio Antenna Measurements -- Demonstration for UAV-Based Near-Field Measurements of Modulated Terrestrial Navigation Signals

Antenna measurements with high signal-to-noise ratio (SNR) require long measurement or integration times of the receiver and can, thus, lead to a very long duration of the measurements, especially if many frequency and spatial samples need to be collected. In order to speed up such measurements, an approach is presented, which collects all measurement samples with short measurement times, performs a Fourier transform of the measurement samples, bandpass filters the desired measurement signals with a small bandwidth, and obtains high-SNR measurement samples according to the short measurement times by inverse Fourier transform. This approach can be utilized with single-frequency continuous wave (CW) transmit signals, but also with transmit signals containing several discrete frequency components, as, e.g., found for periodically modulated CW carriers. The approach is first worked out and demonstrated for simulated test data. Next, it is utilized for the processing of modulated near-field (NF) measurement data collected via an uninhabited aerial vehicle (UAV) at a Doppler high-frequency omnidirectional radio range (DVOR) and at the localizer of an instrument landing system (ILS). The extracted CW NF data is transformed into the far field (FF) and diagnostic information is obtained from the underlying inverse source solutions.

Source: arXiv:2606.23569v1 - http://arxiv.org/abs/2606.23569v1 PDF: https://arxiv.org/pdf/2606.23569v1 Original Link: http://arxiv.org/abs/2606.23569v1