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Earth Observation Satellite 1700 MHz Patch Antenna

The L-Band is carved up for many services and the 1690 to 1710 MHz Space to Earth band is shared with 4G cell phone services, with several geo stationary and polar orbit earth observation satellites operating at 1702.5 and 1707 MHz.  Since I recently made an ADS-B 1090 MHz patch I decided to make one for this higher frequency band, while I am still in the swing of things with my mad antenna carving skillz.

This Right Hand Circular polarized antenna is carved from Rogers RO4350B low loss PCB and after a couple days of meticulous cutting and measuring it is spot on.

It is amazing what one can make if one has enough coffee, chocolate and patience!

Rogers 4350B copper clad circuit board has the following RF parameters:

  • Permittivity Dk = 3.66
  • Loss Df = 0.0031
  • Dielectric width Dw = 0.508 mm
  • Cu 1 Oz = 36 um

This Joint Polar Satellite Service (JPSS) antenna has the following dimensions:

  • Base: 69 x 54.6 mm
  • Patch: 53.3 x 43.4 mm
  • Corners: 12 x 12 mm
  • Slots: 5 x 8 mm
  • Feed: 1.1 x 7.5 mm


A receive antenna does not have to be super accurate, but 0.1 mm makes a measurable difference.  If you have very steady hands, a sharp scalpel, calipers and a reasonable quality Vector Network Analyzer, then you can carve one of your own and see what you get, or you can send me a message and once there are multiple takers, I'll have a batch made at Eurocircuits, next door in Hungary.



La voila!

Herman

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