Optical BEAMTAP beam-forming and jammer-nulling system for broadband phased-array antennas.
← Research streamThe paper describes a broadband adaptive beam-forming and jammer-nulling approach (BEAMTAP) for large phased-array antennas that reduces the number of tapped delay lines required from N to 2 while retaining full NM degrees of freedom. It also outlines an opti…
Study snapshot
Abstract
We present an approach to receive-mode broadband beam forming and jammer nulling for large adaptive antenna arrays as well as its efficient and compact optical implementation. This broadband efficient adaptive method for true-time-delay array processing (BEAMTAP) algorithm decreases the number of tapped delay lines required for processing an N-element phased-array antenna from N to only 2, producing an enormous savings in delay-line hardware (especially for large broadband arrays) while still providing the full NM degrees of freedom of a conventional N-element time-delay-and-sum beam former that requires N tapped delay lines with M taps each. This allows the system to adapt fully and optimally to an arbitrarily complex spatiotemporal signal environment that can contain broadband signals of interest, as well as interference sources and narrow-band and broadband jammers--all of which can arrive from arbitrary angles onto an arbitrarily shaped array--thus enabling a variety of applications in radar, sonar, and communication. This algorithm is an excellent match with the capabilities of radio frequency (rf) photonic systems, as it uses a coherent optically modulated fiber-optic feed network, gratings in a photorefractive crystal as adaptive weights, a traveling-wave detector for generating time delay, and an acousto-optic device to control weight adaptation. Because the number of available adaptive coefficients in a photorefractive crystal is as large as 10(9), these photonic systems can adaptively control arbitrarily large one- or two-dimensional antenna arrays that are well beyond the capabilities of conventional rf and real-time digital signal processing techniques or alternative photonic techniques.
AI evidence extraction
Structured fields below were generated from the paper’s abstract and metadata to make the evidence easier to inspect. Automated extraction may be incomplete or incorrect; verify important details against the original paper.
Main findings
The paper describes a broadband adaptive beam-forming and jammer-nulling approach (BEAMTAP) for large phased-array antennas that reduces the number of tapped delay lines required from N to 2 while retaining full NM degrees of freedom. It also outlines an optical/rf-photonic implementation using a coherent optically modulated fiber-optic feed network, photorefractive-crystal adaptive weights, a traveling-wave detector for time delay, and an acousto-optic device for weight adaptation.
Outcomes measured
- Broadband receive-mode beam forming
- Jammer nulling
- Reduction in tapped delay-line hardware requirements
- Adaptive true-time-delay array processing (BEAMTAP) optical implementation
View raw extracted JSON
{
"study_type": "engineering",
"exposure": {
"band": "RF",
"source": "phased-array antenna / radar/sonar/communication (signal processing)",
"frequency_mhz": null,
"sar_wkg": null,
"duration": null
},
"population": null,
"sample_size": null,
"outcomes": [
"Broadband receive-mode beam forming",
"Jammer nulling",
"Reduction in tapped delay-line hardware requirements",
"Adaptive true-time-delay array processing (BEAMTAP) optical implementation"
],
"main_findings": "The paper describes a broadband adaptive beam-forming and jammer-nulling approach (BEAMTAP) for large phased-array antennas that reduces the number of tapped delay lines required from N to 2 while retaining full NM degrees of freedom. It also outlines an optical/rf-photonic implementation using a coherent optically modulated fiber-optic feed network, photorefractive-crystal adaptive weights, a traveling-wave detector for time delay, and an acousto-optic device for weight adaptation.",
"effect_direction": "unclear",
"limitations": [],
"evidence_strength": "insufficient",
"confidence": 0.74,
"peer_reviewed_likely": "yes",
"keywords": [
"BEAMTAP",
"beam forming",
"jammer nulling",
"adaptive antenna arrays",
"phased-array",
"true-time-delay",
"RF photonics",
"photorefractive crystal",
"fiber-optic feed network",
"acousto-optic device"
],
"suggested_hubs": []
}AI-extracted fields are generated from the abstract and metadata and may be incomplete or incorrect. This material is for informational purposes and is not medical advice.
Identifiers and source
DOI: 10.1364/ao.39.000212
PubMed: 18337889