Overview
Glenn and Andrew tested the v3 cylindrical patch antennas on the HP VNA in the PSU microwave lab. The v3 CPA's PCB's were made last week, and have 1/16" UHMW PE as a dielectric.
Conclusion
The GPS and ATV antennas are dead on. We're very happy with them. The wifi antenna is surprisingly and disapointingly low. It'll still work as a wifi antenna, but it's pretty close to a SWR of 2:1. Why is the wifi different? Is it the 8 feed network? Or?
WiFi Antenna (Design frequency = 2.412 GHz)
FILE00 = 2.362 TO 2.462 GHz CALIBRATION
Antenna was outside of these limits. Moved range from 2.2 to 2.5
SCRN00 = smith
SCRN01 = freq. resp., marker at 2.412 GHz
SCRN02 = freq. resp., marker at resonant
At design: 1.86:1
At resonance: F = 2.3372 GHz, SWR = 1.08:1, BW = 2.2748 GHz - 2.4282 GHz = 153.4 MHz
"knee" of swr curve is at 2.3941 GHz.
Futzing with antenna made absolutely no difference.
SCRN00 = Wifi angtenna smith chart
SCRN01 = Wifi antenna with marker on design frequency
SCRN02 = Wifi antenna with marker on resonant freq.
GPS (Design frequency = 1.57542 GHz)
FILE01 = 1.475 TO 1.575 GHz CALIBRATION
Closer than expected! Moved range from 1.550 to 1.600 GHz
SCRN03 = smith chart with marker at 1.5754 GHz
SCRN04 = freq. resp., marker at 1.57542 GHz
SCRN05 = freq. resp., marker at resonant
At design: SWR = 1.45:1
At resonance: F = 1.5665 GHz, SWR = 1.25:1, BW = 1.5434 GHz - 1.5885 GHz = 45.1 MHz
Futzing with antenna made no difference.
SCRN03 = GPS angtenna smith chart
SCRN04 = GPS antenna with marker on design frequency
SCRN05 = GPS antenna with marker on resonant freq.
ATV (Design frequency = 1.25325 GHz)
FILE02 = 1.2 TO 1.3 GHz CALIBRATION
SCRN06 = smith chart with marker at design freq.
SCRN07 = freq. resp., marker at design freq.
SCRN08 = freq. resp., marker at resonant
At design: SWR = 1.74:1
At resonance: F = 1.2488 GHz, SWR = 1.56:1, BW = 1.2412 GHz - 1.2571 GHz = 15.9 MHz
SCRN06 = ATV angtenna smith chart
SCRN07 = ATV antenna with marker on design frequency
SCRN08 = ATV antenna with marker on resonant freq.
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