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Results of X-band electronically scanned array using an overlapped subarray architecture

October 12, 2010
  |
Conference Paper
Author:
Sean M. Duffy
…
Published in:
2010 IEEE Int. Symp. on Phased Array Systems, 12 October 2010, pp. 713-718.
Topic:
radar
R&D area:
R&D group:

Summary

The measured results from an X-band electronically scanned array using an overlapped subarray architecture are presented. The 2D architecture uses a 12 x 12 element subarray with 3 to 1 overlapping. The active electronic scanned array is a receive only implementation consisting of switch, low noise amplifier, phase shifter and attenuator. Measured far-field patterns and excitation at the aperture using near-field scanner demonstrates desired design goals of a 20 degree sector beam with low sidelobes. Finally, the scan performance of the sector subarray beam is measured at 20 and 40 degrees. A three tile implementation is constructed and measured.
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Summary

The measured results from an X-band electronically scanned array using an overlapped subarray architecture are presented. The 2D architecture uses a 12 x 12 element subarray with 3 to 1 overlapping. The active electronic scanned array is a receive only implementation consisting of switch, low noise amplifier, phase shifter and...

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Results of X-band electronically scanned array using an overlapped subarray architecture

Low-profile dual-polarized UHF array antenna

October 12, 2010
  |
Conference Paper
Author:
Alan J. Fenn
…
Published in:
2010 IEEE Int. Symp. on Phased Array Systems & Technology, 12 October 2010, p. 599-602.
Topic:
antennas
R&D area:
R&D group:

Summary

A low-profile dual-polarized UHF array antenna has been developed for wide field-of-view dual sector coverage in the 250 to 450 MHz frequency range for communications or radar applications. The antenna utilizes a pair of parasitically-tuned dipole arrays for horizontal polarization and a pair of parasitically-tuned monopole arrays for vertical polarization, and both arrays are mounted on a common ground plane. The thickness of the antenna is 18.2 cm. Numerical electromagnetic simulations were used to analyze and optimize the antenna parameters prior to fabrication. Measurements of the dual-polarized prototype in an anechoic chamber demonstrate the antenna?s return loss and dual-polarized radiation gain pattern performance.
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Summary

A low-profile dual-polarized UHF array antenna has been developed for wide field-of-view dual sector coverage in the 250 to 450 MHz frequency range for communications or radar applications. The antenna utilizes a pair of parasitically-tuned dipole arrays for horizontal polarization and a pair of parasitically-tuned monopole arrays for vertical polarization...

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Low-profile dual-polarized UHF array antenna

Low cost multifunction phased array radar concept

October 12, 2010
  |
Conference Paper
Author:
Jeffrey S. Herd
…
Published in:
2010 IEEE Int. Symp. on Phased Array Systems, 12 October 2010.
Topic:
radar
R&D area:
R&D group:

Summary

MIT Lincoln Laboratory and M/A-COM are jointly conducting a technology demonstration of affordable Multifunction Phased Array Radar (MPAR) technology for Next Generation air traffic control and national weather surveillance services. Aggressive cost and performance goals have been established for the system. The array architecture and its realization using custom Transmit and Receive Integrated Circuits and a panel-based Line Replaceable Unit (LRU) will be presented. A program plan for risk reduction and system demonstration will be outlined.
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Summary

MIT Lincoln Laboratory and M/A-COM are jointly conducting a technology demonstration of affordable Multifunction Phased Array Radar (MPAR) technology for Next Generation air traffic control and national weather surveillance services. Aggressive cost and performance goals have been established for the system. The array architecture and its realization using custom Transmit...

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Low cost multifunction phased array radar concept

Ultrawideband VHF/UHF dipole array antenna

October 12, 2010
  |
Conference Paper
Author:
Alan J. Fenn
…
Published in:
2010 IEEE Int. Symp. on Phased Array Systems, 12 October 2010, pp. 79-82.
Topic:
antennas
R&D area:
R&D group:

Summary

A linearly-polarized ultrawideband dipole array antenna has been developed for coverage in the VHF/UHF frequency range for communications or radar applications. The antenna design utilizes a horizontally polarized array of thick tubular dipole elements above a ground plane. Numerical electromagnetic simulations were used to analyze and optimize the antenna parameters prior to fabrication. Measurements of a 24-element ultrawideband dipole array prototype in an anechoic chamber demonstrate the antenna's return loss and gain pattern performance over a wide bandwidth.
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Summary

A linearly-polarized ultrawideband dipole array antenna has been developed for coverage in the VHF/UHF frequency range for communications or radar applications. The antenna design utilizes a horizontally polarized array of thick tubular dipole elements above a ground plane. Numerical electromagnetic simulations were used to analyze and optimize the antenna parameters...

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Ultrawideband VHF/UHF dipole array antenna

Advanced architecture for a low cost multifunction phased array radar

May 23, 2010
  |
Conference Paper
Author:
Jeffrey S. Herd
…
Published in:
2010 IEEE/MTT-S Int. Microwave Symp., 23-28 May 2010, pp. 676-679.
Topic:
radar
R&D area:
R&D group:

Summary

MIT Lincoln Laboratory and MIA-COM are jointly conducting a technology demonstration of affordable Multifunction Phased Array Radar (MPAR) technology for Next Generation air traffic control and national weather surveillance services. Aggressive cost and performance goals have been established for the system. The array architecture and its realization using custom Transmit and Receive Integrated Circuits and a panel-based Line Replaceable Unit (LRU) will be presented. A program plan for risk reduction and system demonstration will be outlined.
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Summary

MIT Lincoln Laboratory and MIA-COM are jointly conducting a technology demonstration of affordable Multifunction Phased Array Radar (MPAR) technology for Next Generation air traffic control and national weather surveillance services. Aggressive cost and performance goals have been established for the system. The array architecture and its realization using custom Transmit...

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Advanced architecture for a low cost multifunction phased array radar

Multifunction phased array radar (MPAR) for aircraft and weather surveillance

May 10, 2010
  |
Conference Paper
Author:
Jeffrey S. Herd
…
Published in:
2010 IEEE Radar Conf., 10 May 2010.
Topic:
radar
R&D area:
R&D group:

Summary

MIT Lincoln Laboratory and M/A-COM are jointly conducting a technology demonstration of affordable Multifunction Phased Array Radar (MPAR) technology for Next Generation air traffic control and national weather surveillance services. Aggressive cost and performance goals have been established for the system. The array architecture and its realization using custom Transmit and Receive Integrated Circuits and a panel-based Line Replaceable Unit (LRU) will be presented. A program plan for risk reduction and system demonstration will be outlined.
READ LESS

Summary

MIT Lincoln Laboratory and M/A-COM are jointly conducting a technology demonstration of affordable Multifunction Phased Array Radar (MPAR) technology for Next Generation air traffic control and national weather surveillance services. Aggressive cost and performance goals have been established for the system. The array architecture and its realization using custom Transmit...

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Multifunction phased array radar (MPAR) for aircraft and weather surveillance

Ultra-wideband offset bicone/dipole antenna: simulations and measurements

March 8, 2009
  |
Conference Paper
Author:
John S. Sandora
…
Published in:
Ann. Rev. of Progress in Applied Computational Electromagnetics, 8-12 March 2009.
Topic:
antennas
R&D area:
R&D group:

Summary

An ultrawideband (UWB) antenna has been developed for operation in the 60 MHz to 18 GHz frequency range. This antenna is a new type--an offset bicone/dipole design that allows for vertically polarized omnidirectional coverage over an instantaneous 300:1 bandwidth. Numerical electromagnetic simulations with the finite-element method (FEM) were used to investigate the antenna concept and optimize geometry prior to fabrication. Measurements both outdoors and in an anechoic chamber confirm the antenna's performance.
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Summary

An ultrawideband (UWB) antenna has been developed for operation in the 60 MHz to 18 GHz frequency range. This antenna is a new type--an offset bicone/dipole design that allows for vertically polarized omnidirectional coverage over an instantaneous 300:1 bandwidth. Numerical electromagnetic simulations with the finite-element method (FEM) were used to...

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Ultra-wideband offset bicone/dipole antenna: simulations and measurements

Extending the dynamic range of RF receivers using nonlinear equalization

February 8, 2009
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Conference Paper
Author:
Joel I. Goodman
…
Published in:
IEEE Conf. on Waveform Diversity & Design, 8 February 2009, pp. 224-228.
Topic:
signal processing
R&D area:
R&D group:

Summary

Systems currently being developed to operate across wide bandwidths with high sensitivity requirements are limited by the inherent dynamic range of a receiver's analog and mixed-signal components. To increase a receiver's overall linearity, we have developed a digital NonLinear EQualization (NLEQ) processor which is capable of extending a receiver's dynamic range from one to three orders of magnitude. In this paper we describe the NLEQ architecture and present measurements of its performance.
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Summary

Systems currently being developed to operate across wide bandwidths with high sensitivity requirements are limited by the inherent dynamic range of a receiver's analog and mixed-signal components. To increase a receiver's overall linearity, we have developed a digital NonLinear EQualization (NLEQ) processor which is capable of extending a receiver's dynamic...

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Extending the dynamic range of RF receivers using nonlinear equalization

The next-generation multimission U.S. surveillance radar network

November 1, 2007
  |
Journal Article
Author:
Mark E. Weber
…
Published in:
Bull. American Meteorological Society, Vol. 88, No. 11, November 2007, pp. 1739-1751.
Topic:
air traffic control
R&D area:
R&D group:

Summary

Current U.S. weather and aircraft surveillance radar networks vary in age from 10 to more than 40 years. Ongoing sustainment and upgrade programs can keep these operating in the near to mid-term, but the responsible agencies National Weather Service (NWS), Federal Aviation Administration (FAA), and the Departments of Defense (DoD) and Homeland Security (DHS) recognize that large-scale replacement activities must begin during the next decade. The National Weather Radar Testbed (NWRT) in Norman, Oklahoma, is a multiagency project demonstrating operational weather measurements capability enhancements that could be realized using electronically steered phased-array radars as a replacement for the current Weather Surveillance Radar-1988 Doppler (WSR-88D). FAA support for the NWRT and related efforts address air traffic control (ATC) and homeland defense surveillance missions that could be simultaneously accomplished using the agile-beam capability of a phased array weather radar network. In this paper, we discuss technology issues, operational considerations, and cost trades associated with the concept of replacing current national surveillance radars with a single network of multimission phased array radars (MPAR). We begin by describing the current U.S. national weather and aircraft surveillance radar networks and their technical parameters. The airspace coverage and surveillance capabilities of these existing radars provide a starting point for defining requirements for the next-generation airspace surveillance system. We next describe a conceptual MPAR high-level system design and our initial development and testing of critical subsystems. This work, in turn, has provided a solid basis for estimating MPAR costs for comparison with existing, mechanically scanned operational surveillance radars. To assess the numbers of MPARs that would need to be procured, we present a conceptual MPAR network configuration that duplicates airspace coverage provided by current operational radars. Finally, we discuss how the improved surveillance capabilities of MPAR could be utilized to more effectively meet the weather and aircraft surveillance needs of U.S. civil and military agencies.
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Summary

Current U.S. weather and aircraft surveillance radar networks vary in age from 10 to more than 40 years. Ongoing sustainment and upgrade programs can keep these operating in the near to mid-term, but the responsible agencies National Weather Service (NWS), Federal Aviation Administration (FAA), and the Departments of Defense (DoD)...

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The next-generation multimission U.S. surveillance radar network

Design of overlapped subarrays using an RFIC beamformer

June 9, 2007
  |
Conference Paper
Author:
Sean M. Duffy
…
Published in:
IEEE Antennas and Propagation Society Int. Symp., 2007 Digest, 9-15 June 2007, pp. 1791-4.
Topic:
antennas
R&D area:
R&D group:

Summary

Electronically scanned arrays require a minimum number of controls, Nmin, given by the number of orthogonal beams that fill a prescribed scan sector. Most practical antenna arrays require considerably more than Nmin control elements, but overlapped subarray architectures can approach this theoretical limit. Figure 1 shows a block diagram of an overlapped subarray architecture. The overlapped subarray network produces a flattopped sector pattern with low sidelobes that suppress grating lobes outside of the main beam of the subarray pattern. Each radiating element of the array is connected to multiple subarrays, creating an overlapping geometry. It is possible to scan one beam, or a fixed set of contiguous beams, over the main sector of the subarray with a set of Nmin phase shifters. Alternatively, digital receivers can be connected to the Nmin subarrays and multiple simultaneous beams can be formed digitally. Digital subarray architectures using a combination of element level phase shifters and subarray level receivers makes it possible to scan multiple beam clusters over all space. The conventional approach to the design and manufacturing of the overlapped subarray network shown in Figure 1 is challenging and costly due to the complexity of the microwave network. However, the design of the overlapped subarray beamformer using Radio Frequency Integrated Circuits (RFIC) represents a novel approach for implementing an efficient trade-off between the agility and capability of fully digital arrays and the cost effectiveness of analog arrays.
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Summary

Electronically scanned arrays require a minimum number of controls, Nmin, given by the number of orthogonal beams that fill a prescribed scan sector. Most practical antenna arrays require considerably more than Nmin control elements, but overlapped subarray architectures can approach this theoretical limit. Figure 1 shows a block diagram of...

READ MORE
Design of overlapped subarrays using an RFIC beamformer
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