Biquad Antenna

[Admin 2546]

,, you're not interested in the Batwing antenna ... ??

,,, or so it may be...

[Admin 2546]

,,, something like that ... !!!

[RC-Concepts 3]

On 06/05/2020 at 2:14 PM, Admin said:

,,, something like that ... !!!

Thanks for the tip. 45degrees will cover both vertical polarization and horizontal polarization too. I have changed the transmitting antennas to vertical polarization so I have all 4 Biquads positioned in vertical polarization (horizontal bow-tie) now.

I did more range test in different urban evironments and here are the results:

 

[Admin 2546]

,,,hi buddy...!!!

,,, yes, but anyway you did not rotate the antennas by 45 degrees as I showed you...!!!

[RC-Concepts 3]

I tried your 45degrees, but I changed back to horizontal bow-tie. The reason for not using 45degrees is I got a wider horizontal beam with the horizontal bow-ties. For FPV, I need the horizontal beam to be as wide as possible.

[Admin 2546]

,,,hi buddy...!!!

,,, what do you think of this ... ???
,,, would you like to build it...???

PCB diameter = 50mm

[RC-Concepts 3]

On 12/05/2020 at 4:49 PM, Admin said:

,,,hi buddy...!!!

,,, what do you think of this ... ???
,,, would you like to build it...???

PCB diameter = 50mm

Nice, it has a wide beam (Phi). Do you have the dimensions of it?

[Admin 2546]

These files can help you...???!!!

5,8ghz.dxf

5,8ghz.gbr

5,8ghz.gds

[Raymond 1]

Could someone help me, please? I want to make double biquad at 5.8 GHz in CST, but I am new in this software. How to make like this models? Thank you!

[Admin 2546]

Raymond,,,here, is not the place for tutorials...!!!

,,,try creating a new post...1!!!

[Mishka 10]

On 2/11/2018 at 10:00 AM, Admin said:

this file type is not good...??

 

biquad.dxf

biquad.gbr

Hello,

first of all, please let me thank you for sharing the designs! This is absolutely stunning what you guys are doing here.

I'm working with Bluetooth 5 enabled microcontrollers, and for an experiment want to build a long range symmetrical setup using vanilla nRF52840 MCU (+8dBm max). To break 2 km range, I'm thinking about a couple of offset dishes 1m diameter (expect to reach +25dBi), and looking for a suitable feed horn. I have noticed your biquad and batwing antenna designs. Both do promise about +10dBi gain, with the biquad a little bit narrower and hence with better directivity.

I ilke that they can be manufactured on FR4 which means high reproducibility and hence low error margin. Also, I'm going to further tune the antenna with matching network to better match my source. However, I've noticed that the DXF / Gerber files (cited above) are not fully correspond to the dimensions on the CST screenshots listed for a very similar 2.44 GHz design - DXF / Gerber is bigger.

Could you point me to the most decent model for 2.442 GHz, please?

Also, may be there a better option to take the feed horn role?

Thanks!

[clanon 247]

only 8dbm (6mw) 

you might wanna stay AWAY from any DIELECTRIC...(efficiency would be lost ) power would be lost

 

Edited August 5, 2020 by clanon

[Mishka 10]

1 hour ago, clanon said:

only 8dbm (6mw) 

you might wanna stay AWAY from any DIELECTRIC...(efficiency would be lost ) power would be lost

 

Pretty much agree, thanks for the point. This will probably to decrease it by 1 dBi or such. So I could laser cut it from a copper plate instead.

But this means that a different model needed.

Also, I think that I'm going to fix the biquad to the reflector with two plastic struts, and for the feed line I'll use an SMA bulkhead extension cable from Amazon, like this one https://www.amazon.com/Bingfu-Bulkhead-Cellular-Amplifier-Transmitter/dp/B07MJQWH8S On the board side there is the U.FL connector.

 

[clanon 247]

you may wanna study feeds efficiency (spillover ,etc) for you desired Dishes...anything close to 70%or more would be GREAT for your project...(over 20dbi gain should be enough , if there are NO LOSSES (dielectrics , cables , connector , mismatch ,etc) and if it is only BLUETOOTH ,,,you may use high Q factor centered on your band,,,NO need for wide Bandwidth...there

[Mishka 10]

47 minutes ago, clanon said:

you may wanna study feeds efficiency (spillover ,etc) for you desired Dishes...anything close to 70%or more would be GREAT for your project...(over 20dbi gain should be enough , if there are NO LOSSES (dielectrics , cables , connector , mismatch ,etc) and if it is only BLUETOOTH ,,,you may use high Q factor centered on your band,,,NO need for wide Bandwidth...there

I'm going to use a pair of cheap offset satellite mirrors of about 80 cm diameter. Looks like most of them were designed with F/D ≈ 0.5, hence the feed antenna should fit vast majority of its radiation into 90 degrees beam. I don't expect the mirrors will be of high quality, but I believe they're big enough to compensate some errors. Also, I'll try to align focal points.

The link budget with monopole omnidirectional antennas (I assume 0dBi) and +8dBm PA on transmitter side is 104 dB which results in about 1600 m of theoretical range. I hope to break this 2 km barrier with directional antennas first (supposed to be +10 dBi each) which hopefully results in 5+ km range. And then with the satellite dishes (hope to achieve +25 dBi per node) to reach 10 km. Unfortunately, this is the maximum distance in my area where I may have more or less clear Fresnel zone. There is also 20 km line of sight, but there is a hill between the points.

[clanon 247]

This is with a TP LINK kinda of dipole on 1.26 regular parabolic dish...0.2 or so F/d ratio...(hard to feed)

https://www.wifi-antennas.com/uploads/monthly_2020_07/5f05b71ad1d7f_126m.JPG.3d12cb9d42e94a87de9f02d81677a212.JPG

i like the VE4MA and chaparral feeds for Efficiency...but still collating...not sure (big area both...)

[Mishka 10]

Reading here and there I found that the Bester antenna may be another option. For 2.44 GHz there are two designs, with one director (9.5 dBi) and with seven directors (14.5 dBi).

Any thoughts, how is the Bester in comparison to the biquad? Which one is be better for a satellite dish?

[Admin 2546]

Simple Bester antenna on a satellite dish, is better than biquad antenna but it is harder to execute...!!!

[Mishka 10]

1 hour ago, Admin said:

Simple Bester antenna on a satellite dish, is better than biquad antenna but it is harder to execute...!!!

Many thanks for the advice! I'm going to build the following one. Will post questions / updates to the "2.4GHz yagi" topic.

[Admin 2546]

,,,no,this one,,,

[Mishka 10]

22 minutes ago, Admin said:

,,,no,this one,,,

Oh!

Have some more questions, but to keep the biquad topic clean please see my reply in the "Bester Antenna".

[Newbe 0]

thanks for sharing, and i have made a biquad antenna according to your instructions so i get signal gain. next i want to make yagi 9 antenna but i don't know if this will work because i will be using 2 millimeter wire medium recommended is 1.6 mm.

[Admin 2546]

,,, okay, but try not to post so many images in the dubbing and put it under Spoiler...!!!

[Hamza 43]

https://onlinelibrary.wiley.com/doi/full/10.1002/mmce.22037    here  you can find new biquad   higher gain  and wider band 

[Hamza 43]