Low Noise Amplifiers and Line Feeds for Cylinders

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Low Noise Amplifiers and Line Feeds for
Cylinders

• Peter Timbie
• UW-Madison
• Dept of Physics

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Gawande, Wadefalk, Weinreb LNA with GaAs mHEMT

• 3 stages of amplification
• runs at 300 K

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Gawande, Wadefalk, Weinreb LNA Designwith SiGe
transistors
RF in
RF out
transistors go here
BFP740F
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WSTAR

• 3 - element interferometer for 21 cm
• student training

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WSTAR Receiver
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Belostoski Haslett CMOS LNA
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2007, IEEE Ant. and Prop. Soc. Int. Symp.

• Molonglo Observatory
• Synthesis Telescope
• 11.6 x 778 m cylinder
• 300 - 1400 MHz

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MOST Linefeed
1.4 m
?c/2
fc 866 MHz, ?c 35 cm
?c/4
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Linefeed for Cylindrical Antenna
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MOST Linefeed Element Beam Patterns, Transverse
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MOST Linefeed Element Beam Patterns, Transverse
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MOST Linefeed Element Beam Patterns,
Longitudinal700-1100 MHz
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Phased Array of Vivaldi Antennas (Veidt et al
2007)

• Phased Array Feed Demonstrator
• (PHAD)
• 1-2 GHz
• elements spaced 7.5 cm
• ?/2 at shortest wavelength
• testing at Parkes

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