antenna and transmission line site

[flatulent]

www.amanogawa.com has a bunch of applets on antenna patterns and .pdf files of theory. This is very good for beginners.

 

[Lupin]

Hi,
I'm involved in a study of linear and planar phased arrays. I'm looking for formulas of Directivity. I've been writing a code. The general formula of the Directivity must be checked for particular cases (uniform array..).
Can u help me?

Thanks in advance
Lupin

 

[flatulent]

The books by Kraus have thes equations. The easiest test case is broadside with the elements a half wave apart. The field should all add up on the axis perpendicular to the plane containing the radiators.

 

[Lupin]

Sure! I checked the case (u mentioned) of uniform excited (in Am and Ph) isotropic radiators (and my code was right for the computation of Directivity, nulls'position, beamwidth, sidelobes level).. anyway I'ld like to make a "cross check" with other configurations such as not uniform excited arrays, not equispaced arrays, not isotropic radiators.. For this purpose I implemented the Directivity general equation, to check its results I'm using some commercial code but it doesn't consider all the cases I 'm working on.
So if u can write me the title of Kraus's books where the formulas I'm looking for are contained , I can implement them and make another cross check with my code.

Thanks for your cooperation
Lupin

 

[flatulent]

The book title is Antennas. The math for the phased arrays is identical to that for FIR filters with the spacing in wavelengths between radiators is related to the time between samples.

Some simple cases to try is binomial weighting which will give no sidelobes. For phase testing you can do an endfire array.

Some years ago it was amusing to see the reinvention of 50 year old antenna technology being claimed as scientific research in DSP.

 

[iambbcat]

Hi flatulent , I'm looking for some articles about PIFA antenna ,can you tell me where to find it ? thanks