TechRxiv
main.pdf (2.76 MB)

Wideband RFI Cancellation for High-sensitivity Phased Array Receivers with True Time Delays and Truncated Hadamard Projection

Download (2.76 MB)
preprint
posted on 25.07.2021, 14:07 by Jakob KunzlerJakob Kunzler
Radio frequency interference (RFI) is a significant challenge for high-sensitivity phased array instruments. RFI can be suppressed using digital signal processing, but to improve dynamic range for wideband RFI, it can be desirable to remove interference in the analog domain before sampling. In previous work, it has been shown that analog true time delay (TTD) stages with a truncated Hadamard transform can place a wide-band spatial null on RFI from a given direction of arrival. We show that TTD and Hadamard projection is mathematically equivalent to the classical, narrow-band subspace projection beamformer, but with a structure that allows efficient implementation in analog circuitry. Simulation results show that TTD and Hadamard projection can place deep nulls on wideband RFI signals and still achieve SNR performance comparable to the optimal digital maximum signal to interference and noise ratio beamformer.

Funding

2030165

2030159

History

Email Address of Submitting Author

jake.kunzler@gmail.com

ORCID of Submitting Author

0000-0002-0404-6976

Submitting Author's Institution

Brigham Young University

Submitting Author's Country

United States of America