Register to reply

Horn Antenna Radio Interferometer

by rattis
Tags: antenna, horn, interferometer, radio
Share this thread:
rattis
#1
Apr21-08, 03:55 PM
P: 41
This is a strange experiment (or not so compared to some of the experiments I've done) that I am currently undertaking, and require your help.

I have built an interferometer of sorts. Two metal funnels of diameter 200mm are attached together by copper tubing (20mm?) through a Y junction with all angles of 120 degrees. The distance between the centre of the funnels is 600mm. The lower tube connects directly into an LNB.

I am trying to connect the LNB to a voltage data logger via a device called a satellite finder that is basically an analogue dial voltmeter. Currently the software isn't working, but it should do the job.

What I need your help with.
I don't know if it (what ever it is) will work, and if it does, why? I can't find any (seemingly) relevant equations.
Phys.Org News Partner Physics news on Phys.org
UCI team is first to capture motion of single molecule in real time
And so they beat on, flagella against the cantilever
Tandem microwave destroys hazmat, disinfects
mgb_phys
#2
Apr21-08, 04:24 PM
Sci Advisor
HW Helper
P: 8,953
Unless there is some sort of mixer in the Y junction you haven't built an interferometer.
It sounds like you are trying to make a directional signal detector.
I would have thought you want to connect a LNB to each funnel and measure the relative signal strength of each.
You will have to do some caibration because the Feed+LNBs are unlikely to be perfectly equal gains and sensitivity.
rattis
#3
May5-08, 04:14 AM
P: 41
Got this setup and it actually works! One can see some excellent fringes when a person walks past it, and there's certainly some stuff going on when a sweep of the sky is made.

can anyone give me an equation relating the intensity of the em radiation detected and the size/angle of the horns? Or just some general electrostatics relations

rattis
#4
May13-08, 04:43 PM
P: 41
Horn Antenna Radio Interferometer

If anyone is interested, it works exceptionally well. Interference fringes are observed, and when sweeping the southern horizon, a pattern that is significantly similar to that obtained with a standard parabolic reflective dish is observed.


Register to reply

Related Discussions
Satellite TV & Radio dish & antenna question Electrical Engineering 19
Frequency of horn Introductory Physics Homework 4
How does a Radio Antenna Work? General Physics 8
Inductance caused by radio antenna Introductory Physics Homework 0