A Current Evaluation of the Digital Beamforming Testbed at Rome Laboratory
Abstract
The purpose of this report is to provide a recent evaluation of the digital beamforming (DBF) testbed at Rome Laboratory, Hanscom AFB, MA. Section 1 of the report provides a brief introduction to digital beamforming and some of the associated concepts. Section 2 briefly discusses each component of the digital beamforming system (form and function) in a top-down fashion. Section 3 discusses some system limitations associated with the receiver architecture and outlines the techniques used to investigate these limitations. Section 4 contains the measurement results, which show in-phase and quadrature errors approximately 27 dB below the signal, and dc offsets approximately 37 dB below the signal. Third order harmonics are also approximately equal 37 dB below the signal. Amplitude variation among the channels is + or -2dB. Removal of the dc offset error had little effect on a 40 dB Taylor pattern. However, removal of the in-phase and quadrature errors (the dominant errors) greatly improved the pattern. Also included are simple examples of super-resolution of two sources spaced about 1/2 beamwidth apart, and of open-loop adaptive nulling for a 20 dB Taylor pattern. Digital beamforming, Adaptive array, Error effects, Error corrections.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1993
- Accession Number
- ADA274311
Entities
People
- Hans Steyskal
- William R. Humbert
Organizations
- Rome Laboratory