Starlink Antenna

[VK3YNV]

Some more interesting trivia related to patch antenna design.

"In a fragmented aperture, the radiating element isn’t a single piece of copper. Instead, it’s pixelated, like an array within an array (Fig. 1). Such an approach not only helps reduce the parasitic coupling between elements, but it also helps increase gain and improve sidelobe performance."

https://www.mwrf.com/technologies/s...iciency-with-fragmentedaperture-phased-arrays

 

[BillC]

Wonder how the the feed is coupled ?.

 

[VK3YNV]

Wonder how the the feed is coupled ?.

Hi Bill, My simplistic way of understanding it is, the patch layer is an array of directors, the driven elements are spaced a short distance behind the director layer, so it's like an array of lots of little yagis with funny shaped directors. Then by changing the phasing between the hundreds of little yagis they can make the combined beam point whereever they like.

It's like the slew switches on the curtain arrays at radio australia, where they could slew the beam +-30 degrees or so.

 

[BillC]

Hi Ray perhaps there is a driver transistor for every little yagi too. Must be able to phase the multiple inputs instantly individually to any degree . Sounds tricky .Thanks Ray..

 

[VK3YNV]

Hi Bill,
The drivers are specialized IC's like the Renesas 8 channel 28 GHz transmitter. This chip can drive 8 x 28-30GHz transmitters with phase and gain control of each transmitter individually. So the driven elements would be arranged so that by varying the phase the overall beam direction can be controlled.

Here's a more general description.
https://www.analog.com/en/analog-di...-beamforming-ics-simplify-antenna-design.html

 

[BillC]

Thank you Ray ,I have looked at those links ,very interesting . The precision in the manufacture of the chips must be incredible .