[time-nuts] Re: Composite sky GPS - with an added digression

[Lux, Jim]

On 7/1/23 4:03 PM, Hal Murray via time-nuts wrote:
> Jim Lux said:
>> Non ideal antennas make the grating lobes wiggle or be wavy along their long
>> axis. Of course what YOU care about are the nulls (and to a lesser  extent
>> the phase smoothness as you traverse the pattern).  I've looked a lot of
>> these kind of models and your saving grace is that the nulls are deep only
>> when the signals from the antennas are equal strength, which doesn't really
>> happen much.
> In the case of interest, the signal strength will be strongly unbalanced.
>
> It would be interesting to plot the signal strength as a satellite goes from
> one receiver to the other.  You could make several plots with the antennas
> pointed up at different angles so the field of view would overlap more or less.
>
> What do I need to combine a pair of antennas?
>
>
>
Did some sample plots in a subsequent post.

You'd need a power combiner - which is just a splitter used in reverse. 
Depending on signal levels and whether there are LNAs on the antennas, 
it could be as simple as just hooking the antennas up in parallel.

If you're an all passive system, then something like a Minicircuits 
ZX10-2-25 (or any of a dozen or more) would do. With a dB hit from the 
loss through the combiner.

https://www.minicircuits.com/WebStore/dashboard.html?model=ZX10-2-25-S%2B