[time-nuts] GNSS Antennas (was: Rooftop antenna and splitter)

[Peter Monta]

Hi Attila,


The "good" patch antennas thus
> employ a four point feed, but this makes the whole antenna quite a
> bit more expensive, as a 0°/90°/180°/270° phase spliter/hybrid is
> needed. Of course, any such circuit is rather difficult to make
> wide-band and thus becomes the bandwidth limiting element.
>

Mini-Circuits has such a 4-port phase splitter, part number SCQ-4-1650+.
It's $25, which is not super cheap, but it's unclear one could implement
such a network with a planar circuit for less, and the planar circuit would
be more bulky.  I've been thinking of picking up one of these to give an
untuned 4-filar helix a try (not a fancy resonant backfire quadrifilar
helix, which are hard to make broadband, but just a plain set of 4 helices
and the combiner).

>From the data sheet it's clear they have GNSS in mind, and it is quite
broadband:

https://www.minicircuits.com/pdfs/SCQ-4-1650+.pdf

Cheers,
Peter