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Ceramic:AluminaSapphire

9.89.4, 1.6

0.00040.0001

ExcellentExcellent

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Semiconductor:Silicon 11.9 0.0004 Excellent High

Ferrimagnetic:Ferrite 9.0 0.001 Excellent Medium

Synthetic:PTFEPolyphenylene oxide

2.12.55

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PoorGood

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2.17 –2.5510.2

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Microstrip Feed Types

Characteristics Coaxial-probe feed

Radiating Edge

Coupled

Non-radiating

Edge Coupled

Gap Coupled

Inset Feed

Proximity Coupled

Aperture Coupled

CPW Feed

Configuration Non planar Coplanar Coplanar Coplanar Coplanar Coplanar Coplanar Coplanar

Spurious feed radiation

More Less Less More More More More Less

Polarization Purity

Poor Good Poor Poor Poor Poor Excellent Good

Ease of fabrication

Soldering and drilling

needed

Easy Easy Easy Easy Alignment required

Alignment required

Alignment required

Reliability Poor due to soldering

Better Better Better Better Good Good Good

Impedance matching

Easy Poor Easy Easy Easy Easy Easy Easy

Bandwidth 2-5% 9-12% 2-5% 2-5% 2-5% 13% 21% 3%

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Name of Project Frequency

of operation

Antenna Type Gain Beamwidth (degrees)

Az Ele

NASA AIRSAR P-bandL-bandC-band

All Microstrip 14dBi18dBi24dBi

198

2.5

384450

CCRS C/X SAR C-bandX-band

All Horn 26.0dBi28.5dBi

3.31.4

2526

DLR E-SAR P-bandL-bandS-bandC-bandX-band

MicrostripMicrostripMicrostripMicrostripHorn

12dBi17dBin.a.17dBi17.5dBi

3018201917

6035353330

NASDA X/L-band SAR

L-bandX-band

MicrostripWaveguide-slot

18dBi 26.5dBi

2.32.3

4040

DCRS EMISAR L-bandC-band

All Microstrip 17.1dBi26.0dBi

102.4

4231

Lynx Ku-band Horn-fed dish n.a. 3.2 7

PHARUS SAR C-band Microstrip n.a. 2.3 24

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Width of patch, W 16.476 mm

Length of patch, L 12.611 mm

Feeding point offset from edge, xf 3.97 mm

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3.5

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4.5S tanding Wave Ra tio (S WR) at Input P ort

Frequency (GHz)

Magnitude of S

WR

5.890 GHz 6.106 GHz

6.054 GHz 5.939 GHz

216 MHz

115 MHz

Simulation Measured

At 6GHz

Standing wave ratio 1.21 1.41

Reflection coefficient -20.5dB -15.319dB

Gain 5.86dBi 5.7dBi

Bandwidth

For SWR<1.5 115MHz 92.4MHz

For SWR<2.0 216MHz 206MHz

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1 2 3 4 5

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Phase (deg) -164.23 -161.13 -155.69 -119.79 0

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103.75Ω -50Ω λ/4

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65.10Ω -50Ω λ/4

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50Ωtransmission line as phase

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102.61Ω -50Ω λ/4

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65.55Ω -50Ω λ/4

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50Ωtransmission line as phase

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101.56Ω -50Ω λ/4

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1.5

2

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3

3.5S tanding Wave Ratio (SWR) at input port

Frequency (GHz)

Magnitude of S

WR

6.082 GHz 5.949 GHz

5.983 GHz 6.046 GHz

133 MHz

63 MHz

Simulation Measured

At 6GHz

Standing wave ratio 1.29 1.16

Reflection coefficient -17.83dB -22.632dB

Gain 16.2dBi 15.8dBi

Bandwidth

for SWR<1.5 63MHz 83.9MHz

for SWR<2.0 133MHz 135.9MHz

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Excitation coefficient

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Element no. 8 9 10 11 12 13 14

Excitation coefficient

2.4528 2.7003 2.9211 3.1078 3.2540 3.3543 3.4054

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At 6GHzStanding wave ratio 1.11 1.22Reflection coefficient -25.50dB -20.097dB

Gain 17.0dBi 16.6dBi

Bandwidth for SWR<1.5 145.1MHz 168.1MHz

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Frequency (GHz)

Magnitude

145.1 MHz

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0 20 40 60 80 100 120 140 160 180-40

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SWR < 1.5 168MHz (2.8% of f0)

SWR < 2.0 224MHz (3.7% of f0)

Measured gain, G 21.2dBi

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Centre frequency 6GHz 6GHz

Beamwidth AzimuthElevation

30

240 (shaped)2.940

240 (rms error 0.43dB)

Bandwidth (SWR < 1.5) 20MHz 168MHz

AASR (at prf = 1000Hz) < -20dB -26.9dB

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-30dB (all)

-15dB (all)

-16.2dB (peak), ≤ ±0 from broadside-20dB (peak)

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= received signal from a scatterer at R

= received signal from a scatterer at R with an

aircraft LOS displacement of δR

01

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