Sounds like 11ghz can thread a needle.
If I'm going through a treeline I'm probably doing 2.4 or 900....or 3.65.
On 12/19/2018 12:57 PM, [email protected] wrote:
You made me think a bit.
Consider 11 GHz. One 2 mile link and one 10 mile link.
15’
34’
I presume the online tool is calculating 60% of the first fresnel zone.
So half that would be the opposite side of a right triangle.
arc tan of 7.5/10560 = .04 deg
arc tan of 17/52800 = .018 deg
So double that for the diameter of the cone based on the distance and
angle you have almost 1 full degree and a third of a degree. Pretty
small circles. May as well call them a dot when viewing through the
camera.
*From:* [email protected]
*Sent:* Wednesday, December 19, 2018 10:12 AM
*To:* AnimalFarm Microwave Users Group
*Subject:* Re: [AFMUG] Fresnel scope?
I toyed around with this idea last night. I think the angle of view of
most phones is too wide. Doing the rangefinder math for my iPhone 6s a
1 meter dish at 1 km would be less than 4 pixels across at full
resolution (4032x3024). The 5.8 GHz fresnel radius would be 3.6 m or
only 52 pixels. Of course, this would grow larger if calculated closer
to the user—even as the fresnel zone shrank—but I don’t have the
calculus chops to figure out the ideal size to indicate “this area
should be clear no matter how far away”
December 18, 2018 8:58 AM, [email protected] wrote:
I guess you could run a calibration routine where you take a photo
of some linear feature that exactly fills the frame and tell the
phone how far away it is and how wide it is.
*From:* Brian Webster
*Sent:* Monday, December 17, 2018 10:09 PM
*To:* 'AnimalFarm Microwave Users Group'
*Subject:* Re: [AFMUG] Fresnel scope?
Right and since you know the frequency and total path distance, if
you used a laser range finder to put the spot on an obstruction
you would know that distance and could calculate the size of the
zone at that obstruction distance. Might be able to do some
Pythagorean math on the other side of an obstruction to determine
the width of the “hole” through to see if it is wide enough for
the zone clearance at that distance? This might be a bit too much
for an app that would work on all phones but I wonder if it would
be easier to make it work on an outboard camera with the known
lenses and rangefinder configuration and just use the phone to run
the calcs.
Thank You,
Brian Webster
www.wirelessmapping.com <http://www.wirelessmapping.com>
www.Broadband-Mapping.com
*From:*AF [mailto:[email protected]] *On Behalf Of *Chuck McCown
*Sent:* Monday, December 17, 2018 8:40 PM
*To:* AnimalFarm Microwave Users Group
*Subject:* Re: [AFMUG] Fresnel scope?
I guess you could enter the distance of the link and the camera
field of view. With that you could put some circles on the screen.
*From:*Jeremy
*Sent:*Monday, December 17, 2018 6:13 PM
*To:*AnimalFarm Microwave Users Group
*Subject:*Re: [AFMUG] Fresnel scope?
What about integrating it with one of these laser rangefinders
that are fairly cheap now? The tech exists to make this product
work, but I am not sure if there is a big enough market to justify
the R&D.
On Mon, Dec 17, 2018 at 6:12 PM Chuck McCown <[email protected]> wrote:
The challenge would be to know the distance to the obstructions.
*From:*Steve Jones
*Sent:*Monday, December 17, 2018 6:06 PM
*To:*AnimalFarm Microwave Users Group
*Subject:*[AFMUG] Fresnel scope?
Anybody every toyed with making some kind of fresnel scope for
installers?
Like a rangfinder with a red, orange, yellow, and green opaque
overlay that you dial your freq and range and it adjusts the
rings?
Having been doing the installers job for almost a year and
seeing the "gap in the trees" theyve been shooting through,
explains alot of the performance issues.
A phone app would be cool cause you could do a field of vision
screenshot. But i dont know how that could be calculated with
much accuracy given the differences in cameras
Would be really cool if the adjustable rings could be used to
identify beneficial obstructions for mitigating destructive
multipath.
I cant see the concept being all that complicated, you would
know the magnification, field of vision and distance from the
eye. Making the circles adjust like miltiple irises would be a
might bit complicated though.
------------------------------------------------------------------------
--
AF mailing list
[email protected]
http://af.afmug.com/mailman/listinfo/af_af.afmug.com
--
AF mailing list
[email protected]
http://af.afmug.com/mailman/listinfo/af_af.afmug.com
------------------------------------------------------------------------
--
AF mailing list
[email protected]
http://af.afmug.com/mailman/listinfo/af_af.afmug.com
------------------------------------------------------------------------
--
AF mailing list
[email protected]
http://af.afmug.com/mailman/listinfo/af_af.afmug.com
------------------------------------------------------------------------
--
AF mailing list
[email protected]
http://af.afmug.com/mailman/listinfo/af_af.afmug.com
--
AF mailing list
[email protected]
http://af.afmug.com/mailman/listinfo/af_af.afmug.com
