txline;awr

Hello ngstty,

You need feedline to the patch through a matching network which is a quarter-wave transformer (as shown)..

For the width and length of the quarter-wave transformer and 50 Ω feedline
determined by using the Txline Calculator available in AWR MWO software.

As shown in the attached screenshot of the Txline Calculator.
However the value that obtained from Txline Calculator will be modified to suitable value suite
with the help of EM Simulator with the antenna.

The Txline calculator available freely on AWR website...
http://web.awrcorp.com/Usa/Products/...ducts/TX-Line/

Hi,

problem is matching, several solutions is in the attachment. But you need software :(

try TXLine - is it answer higher

try http://www.microwaves101.com/encyclo...nna_ustrip.cfm

about patch antenna, try follow:

or http://www.ece.rutgers.edu/~orfanidi/ewa/ ch 18

or try search in the edaboard: microstrip antenna, or try google.com or http://books.google.com/

or http://www.scialert.net/qredirect.ph....51&linkid=pdf

or http://ece.wpi.edu/mom/index.html

or http://etd.lib.fsu.edu/theses/availa...d/Chapter3.pdf

or http://rze-falbala.rz.e-technik.fh-k...0LabManual.pdf

or try there http://www.pdf-search-engine.com/ write "microstrip antenna"

I hope, that is answer on your question....

i mean what is the lenght of the feed ....

is there any particular formula to find the length of the feed

I think, that the answer Manjunatha_hv is good. You must use software TXLine

1) find impedance your microstrip antenna - easy, set right colum "Physical Cahrakteristic" and click left left arrow - you have impedance Zm

2) calculate Zx = √(Zm*50), this is impedance transformer

3) in left colum set Zx, electical length is 90 deg - click right arrow and you have design λ/4 transformer

4) set left colum 50 Ω and you have feed. In this case the length is
not important, you can have it 50 mm or 50 cm or 4.35 km :) (if you have loss free material)

thats all, do you undestand me ? if not, give me question

Hii manju
what would be the length of lambda/4 transformer,also does this act as a biasing circuit,
if you could give us some document with all the calculations for each and every component it would be ideal

rgds
jagath

Hi,
i do not know, if I understand exactly, but your question is : What is length of transformer ? Answer: Is it lambda/4 :). And lambda/4 = "electrical length 90 deg"

May be try this:

http://www.arcticpeak.com/antennapag...ransformer.htm

I have not document, I have it in my head :)

If you need "all the calculations for each and every component" , you can use TXLine.

I dont know exactly, where is the problem, can you give me more specification question ?

hii
ok from the begining
i have designed a LNA using micrstrip line useing BFG425W transistor but i dont know how to bias the trasistor in the pcb, appreciate if you could help

rgds
jagath

PS:
hii
ia m designing a low noise microstrip amplifier but i have a problem i dont know how to doo the biasing part i have seen a article in www.rfic.co.uk but it does not mention how to doo the calculation for biasing part component values pleas ehelp me out

rgds
jagath

eee,

I think, that this is absolutly another case. LNA is not so easy. You must use some good software. Sorry, I cant help in this case, I do not remember, how can you do it.
I made it a long time before. May be later....

but the length feed is not important...

I think, that will be better do new topic with label: LNA

using pcad

can any body tell what is the formula for impedance of micro strip fed rectangular patch antenna.

can anybody tell which one is the best technique for qw transformer out of the three shown above and why?
or does it depend?
Thanks

The length doesnot seem to be important, all you have to optimise is the width of the strip, that component will determine the impedance of the strip

Hi,

Try with the Excel sheet, I did it for my reference....