design references on printed quasi yagi

printed quasi yagi

Hi everybody,

Could someone point me some design references on planar quasi- Yagi antennas on microstrip substrate?

10x, Al

Hi AL0117,

The 'home' of the Quasi-Yagi Antenna is the university of california. The 'father' is Mr. Tatsuo Itoh. Check the page at **broken link removed**. Once I found an interesting document about planar yagis on the net, but it seems to be away. So I upload it here (and hope that nobody will find it on the net...)

Bye

Re: printed quasi yagi

Hi,
you can download my presentation about Quasi-Yagi Antenna

regards

Re: printed quasi yagi

Hi AL0117
you can find Quasi-Yagi and Microstrip-to-CPS projects (that simulated by Ansoft HFSS) in bellow.
regards

Re: printed quasi yagi

and Microstrip-to-CPS files.

Re: printed quasi yagi

Wow, I really thought that this was my answer.

But I find the QY highly depends on surface waves, and requires high perm dielectric. I'm doing stripline, in a very low permitivity substrate (2.2), total thickness 3mm, and have no flexibility therein. It'll be an injection-molded, very compact and highly directional antenna. It may seem that I could change this, but I can't.

I thought about sandwiching copper between two wafers of ceramic, and encase a la LTCC, but too hard to manufacture. (read, costly)

Maybe I'm back to the humble p-a-t-c-h (why is the board changing this word to "fix"?), in a dual phased array...

Re: printed quasi yagi

i hope that these paper can help you

Re: printed quasi yagi

Hi,

Look at the book RF Technologies for Low Power Wireless Communications by Itoh et al., (chapter 9) available in this forum.

Z

Re: printed quasi yagi

Hi Quantumstate

Some times ago, I found the same problem with the QY antenna. I needed a endfire-radiator, which was not possible to build with P-A-T-C-H.
Now I'm using an array of slot-antennas, which also suffers from surface waves but in a much lower degree than the QY. I can also reach endfire characteristics.

Bye

Re: printed quasi yagi

My presentation about Quasi-Yagi Antenna

Re: printed quasi yagi

and first part

How long need the QY director ?

Re: printed quasi yagi

The attached pdf has good comments about design a Quasi-Yagi Antenna

Dear KMPA
Do u have a full version of you last post? thank you

Re: printed quasi yagi

You guys are the best.

KMPA, I'll try to DL your files, but doubt I have the credits. Got lots of (cough) philes, but maybe I can't UL them here.

I should say that, although I have a graduate degree in finance, and am highly-trained in electronics besides, I have not been able to figure out HFSS9.0. The problem is, drawing tools are so primitive. I'm sure it's quite good for core analysis, but got to give it food, first. And I've never learned Autocad, but may have to.

Nevertheless, I've tried to struggle along with Designer. I can draw planar structures and run 2.5D simulations with it, but for the life of me, I cannot figure out how to connect schematics with layout, which is really where the power is. Yeah, click Layout, but the devices I need, like a balun, are 'virtual'. I place a ladder, and set parameters in schematic editor, but the damned thing never translates to layout, for some reason... still a gheist.

So, I draw pictures and guess and simulate and manually-adjust. Attached is the p-a-t-c-h I guessed, made to exactly the specs given in Designer's Estimate for a circ pol p-a-t-c-h on FR4. Trouble is, it resonates at 3.75GHz instead of the intended 2.445 (according to return-loss). As I move the slots toward the center, freq goes down, but I'm sure efficiency drops too. I'm sure the core problem is my totally guessed-at feedline, but don't know WTF to do about it.

I'll DL what I can, and study.

Re: printed quasi yagi

hi guys,i new user,my thesis in active quasi yagi antenna at x band and c band,i use the most famous and accurate zeland program package,i send the dwsign of yagi at x band,if any buddy have any request pls reply me.
i try to use of the very accurate program xFDTD of remcom.com,but i don't have the complete version ,pls any one have the complete version pls reply me,inow i prepare the active integrated circuit of amp ATF36063
from agilent .com ,at 10 ghz,epr=10.2,h=.635 mm(25 mils)
regards

Re: printed quasi yagi

here my design of yagi antenna at c band with b.w 42% using epsr=2.2 and thick=.7874mm=31 mils
the design using IE3D from zeland
s parameter(*.sp) can be open using excel or by notepad
any comment plsa reply me at my email:
jamywood4000@yahoo.com

Re: printed quasi yagi

for Max232,

Re: printed quasi yagi

KMPA, I've had a chance to review your presentation, and it is excellent. It pretty much solidifies what I'd guessed about the structure -- 180 shift, transformer, balun overall. (But PartI and II seem to be identical)

I'd suggest extending it though, if you have the time. I do not understand the behavior of surface-waves, which are crucial to its operation. Do they envelope the balun only? Or the dipole as well? What's their relation to the groundplane? How is their phase affected by distances? What is their strength/role in air above as well as dielectric below. This knowledge could help with synthesis of enhancements. Also, I can help polish the English, if you like... it doesn't need much at all.

As to me, I've decided that either:
- Ansoft products have poor drawing tools and an indirect, non-intuitive, non-leading simulation philosophy featuring backward M$ thinking, or
- I'm too stupid to use Ansoft products.

So I must press on with my miserable guesses. If I can find it I'll try IE3D, but chances are, I'm screwed. Well, that's life.

Re: printed quasi yagi

Hi ,

you have present an Quasi-Yagi antenna has a single microstrip feed, with a microstrip-to-coplanar strip. If this antenna operated with two feeds,

http://www.mwlab.ee.ucla.edu/publications/2001c/MTTPhoenix/sylvia.pdf


which would be its study?

Thank You