Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

circularly polarized microstrip antenna

Status
Not open for further replies.

suvitha

Newbie level 4
Newbie level 4
Joined
Jan 22, 2007
Messages
6
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,329
how do nearly square patch gives circular polarization?
 

vfurlan

Full Member level 2
Full Member level 2
Joined
Mar 27, 2006
Messages
133
Helped
10
Reputation
20
Reaction score
2
Trophy points
1,298
Location
Slovenia
Activity points
2,185
There are two ways of obtaining:
1. antenna must be fed with two probes
or
2. see **broken link removed**
 

    suvitha

    Points: 2
    Helpful Answer Positive Rating

ananth

Advanced Member level 4
Full Member level 1
Joined
Jun 29, 2004
Messages
113
Helped
56
Reputation
112
Reaction score
43
Trophy points
1,308
Location
India
Activity points
815
Hello Suvitha,
A nearly square microstrip patch gives you circular polarization by activating two modes that have their resonant frequencies very close to the design frequency desired. There are plenty of ways to do this..

A very good article about this is at
h**p://www.mwjournal.com/Journal/article.asp?HH_ID=AR_453

I haven't gone through the mathematics of it all but this is what this article explains.. Another way is to have a truncation on the edges of the antenna to create the same effect being talked about in the above article.. Also, you can find good, although very mathematical, explanation to how this is achieved in the Microstrip Antenna design handbook by Bahl and Bhatia..

If I could add to vfurlan's comments.. it is not necessary to have the antenna fed by two probes.. You can do it with a single probe which is what the above article talks about..

Hope this helps..
Ananth.
 

    suvitha

    Points: 2
    Helpful Answer Positive Rating

bingjiang99

Advanced Member level 4
Full Member level 1
Joined
Apr 27, 2005
Messages
115
Helped
5
Reputation
10
Reaction score
0
Trophy points
1,296
Activity points
2,303
I would like to add two more things:
1)the CP bandwidth will be very limited if the antenna is fed with only one probe.
2)the coupling between two feeding ports should be taken into design considerations if the antenna is fed with two probes

suvitha said:
how do nearly square patch gives circular polarization?
 

    suvitha

    Points: 2
    Helpful Answer Positive Rating
Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top