17-08-2012, 03:19 PM
Microstrip Antenna Designs for Sensor and Communications Applications
[attachment=31880]
Near Field Focused Microstrip Array
Application to low-cost radiometric temperature sensor
Food industry, chemical processing, materials manufacturing
Radiometric technique works through smoke, dust, or steam
Developed by ProSensing Inc (Amherst), and K. Stephan (Texas State U)
12.5 GHz, focus to a spot size of 2.6” at 12” from aperture
Two array versions were designed, fabricated, and tested
Near field testing done at Hanscom AFB
Resulting antenna is substantially smaller and cheaper than original horn
Ku Band Fan Beam Microstrip Array
Application to short range ocean surface topography mapping
Two arrays used for differential phase shift measurement of backscatter
45” long aperture at 16.15 GHz, 2 degree beamwidth
20 dB sidelobe level
Short pulse duration requires time delay feeding across aperture
Loss and space considerations require subarraying (2x4 and 2x6)
Design completed, subarrays tested, final array being fabricated
Improved Bandwidth Microstrip Reflectarray
Microstrip reflectarray uses a flat aperture of microstrip patches with individual phase shifts to form a coherent beam
Reflectarrays typically use variable-length patches, patches with tuning stubs, or CP patches with rotations to achieve required reflection phases
Bandwidth (gain) is generally limited to 2-4% with these methods
A new technique using aperture coupled patches with stub tuners provides much better bandwidth properties,
[attachment=31880]
Near Field Focused Microstrip Array
Application to low-cost radiometric temperature sensor
Food industry, chemical processing, materials manufacturing
Radiometric technique works through smoke, dust, or steam
Developed by ProSensing Inc (Amherst), and K. Stephan (Texas State U)
12.5 GHz, focus to a spot size of 2.6” at 12” from aperture
Two array versions were designed, fabricated, and tested
Near field testing done at Hanscom AFB
Resulting antenna is substantially smaller and cheaper than original horn
Ku Band Fan Beam Microstrip Array
Application to short range ocean surface topography mapping
Two arrays used for differential phase shift measurement of backscatter
45” long aperture at 16.15 GHz, 2 degree beamwidth
20 dB sidelobe level
Short pulse duration requires time delay feeding across aperture
Loss and space considerations require subarraying (2x4 and 2x6)
Design completed, subarrays tested, final array being fabricated
Improved Bandwidth Microstrip Reflectarray
Microstrip reflectarray uses a flat aperture of microstrip patches with individual phase shifts to form a coherent beam
Reflectarrays typically use variable-length patches, patches with tuning stubs, or CP patches with rotations to achieve required reflection phases
Bandwidth (gain) is generally limited to 2-4% with these methods
A new technique using aperture coupled patches with stub tuners provides much better bandwidth properties,