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Antenna circular polarized (clover)

Today I'll show you how to make yourself famous "clover" from IBCrazy.
What is it: a need for stable and long-range FPV video link. If you omit the technical details, it turns out that for the same power in antenna, circular polarization easily interrupts the linear range and stability.
it purple the position of the transmitting antenna in space. In contrast to the linear (normal whip antenna). There is rotate one of the antennas 90 degrees and oppa. Polarization from vertical became horizontal. Ie necessary and the other antenna to rotate as well. If you do not turn, it is a minus signal.
For 2.4 GHz, the sizes to get the antenna oriented in 2440MHz with bandwidth more than sufficient to cover all channels of this group, from 2370 to 2510MHz should be the following:

The length of the Central wire = 3mm

Length of wire = 122,8mm

Long side (the length of the straight segment + length of the Central conductor) = 35,2mm

Short side (the length of the straight segment) = 32,2mm

The arc angle = 90 °

Tilt angle = 50 °

For the range 1.3GHz, with a center frequency of 1280MHz, the dimensions must be as follows:

The length of the Central wire = 3mm

Length of wire = 236,8mm

Long side (the length of the straight segment + length of the Central conductor) = 67,2mm

Short side (the length of the straight segment) = 64,2mm

The arc angle = 90 °

Tilt angle = 50 °

Dimensions for the frequency 5740MHZ, one of the channels points Fat 'shark:

The length of the Central wire = 2mm

Length of wire = 50,9mm

Long side (the length of the straight wire + the length of the Central wire) = 14,8mm

Short side (the length of the straight wire) = 12,8mm

The arc angle = 90 °

Tilt angle = 50 °

This appearance of the antennas at 1.3 GHz (left) and 2.4 GHz (right), in order to give you an idea of sizes:

Constructive Details

PET is better

PMMA
Organic glass (plexiglass), or polymethyl methacrylate (PMMA)...???

The dielectric constant of PMMA is around 4.9....very bad

,,, good, show me such a material in practice ... !!!

For the helix antennas does not really matter dielectric material, but I think the best is Teflon , Polystyrene and the Air

The best material for the construction of the antennas is the sheet, thickness of 0.15-0.5mm

This is from the sheet of aluminum tin cans boxes

A new form of biquad antenna

After a russian model

Putting your phone You are giving the opportunity to the Manager in touch with you for the purchase: access Point wifi Ubiquiti NanoBridge M2 (NBM2)

Optimization Techniques in CST Studio Suite,,,

Optimize in CST.doc

Something like that!
 

The dual polarized microstrip antenna was design to generate signals with  +45 and -45 polarized but with a loss in directivity gain of about 3dBi

This antenna is more interesting with symmetrical excitation at a resonant frequency

DELTA antenna, another kind of miniature antenna on PCB for 5.8GHz

Anyway it's sub-miniature, about 30x30mm

And here are the  CSTfile 

thickness FR4 = 1mm

DELTA 5,8GHz.cst

DELTA antenna, another kind of miniature antenna on PCB for 5.8GHz

This is a 1.2GHz antenna version with pseudo-elliptical polarization

,,,a simple sloted patch antenna for 5,8MHz

dimensions = 4,5x45x45mm

constructive details

on feed point,use this type of connector

"to a friend's request

I did this simulation,,,

I think this type of antenna is better

Double plated PCB

I am going to try to do a simulation, it might be that the ellipse has other dimensions for this antenna

What thickness of PCB did you choose?

for 1.3GHz it is recommended to use elliptical cut

"And these are the latest results

10 minutes ago, antenna_kid said:

what axial ratio has that antenna ?

 

For this, I have to resume the simulation, this project is old for a few years

7 minutes ago, antenna_kid said:

oh, it was under dimensions that you posted for 1mm (under picture). If so, my bad
But no problem with that, I've try make some case so it will shift antenna down

 

then multiplies the dimensions of the image with k = 1,0345 for the frequency of 5,8ghz

36 minutes ago, antenna_kid said:

No you not  you posted biquad2.igs file
As you see i've cut that biquad on CNC. I have small one so it was easy.

But biquad2.igs file is for 1.5mm FR4 thickness,,,,!!!!!

What frequency do you want?