sanchez251
Newbie level 3
Hello guys!
First I want to tell, that I like that site! It's very useful! Second, something about myself: I'm a student of a German technician school and now doing some kind of thesis about RFID. Please remember that I'm a newbe in designing and analizing antennas. Futher I'm sorry for my bad english...
Here is the problem:
One Part of my thesis is to analyze and buid an antenna which works on 866 Mhz (I'm using EPC Gen1 Class2 Transponders EU). The antenna have to be very thin, because it have to lie on the floor ant read all transponders above. Because this I want to buid a microstrip patch antenna with 50 Ohm feed and using a PCB FR4 as substrate (Er = 4.4).
Here I found some help about developing the patch and the microstrip line:
https://www.emtalk.com/mscalc.php
https://www.emtalk.com/mpacalc.php
On basic of this tutorial ( https://www.emtalk.com/tut_1.htm ) I have adapted a existing example to my application. I simulated the patch antenna with HFSS (V10.0), but simulation has shown that the antenna isn't as good as i want. I also built a prototype of this antenna and measured the SWR. It is about 5!
I'll uppload the HFSS-File so you can test it for yourself. For everyone who don't have HFSS here are the dimensions:
f = 866 Mhz
FR4 1.52 mm
Er = 4.4
Patch:
W = 105.41 mm
L = 82.41 mm
Feed: (Have to be 50 Ohm)
W = 2.85 mm
L = 31.35 mm
Waveport:
H = 3 mm
W = 10 mm
What's wrong? Please can someone help me? THX!!!
Regards
Sanchez251
First I want to tell, that I like that site! It's very useful! Second, something about myself: I'm a student of a German technician school and now doing some kind of thesis about RFID. Please remember that I'm a newbe in designing and analizing antennas. Futher I'm sorry for my bad english...
Here is the problem:
One Part of my thesis is to analyze and buid an antenna which works on 866 Mhz (I'm using EPC Gen1 Class2 Transponders EU). The antenna have to be very thin, because it have to lie on the floor ant read all transponders above. Because this I want to buid a microstrip patch antenna with 50 Ohm feed and using a PCB FR4 as substrate (Er = 4.4).
Here I found some help about developing the patch and the microstrip line:
https://www.emtalk.com/mscalc.php
https://www.emtalk.com/mpacalc.php
On basic of this tutorial ( https://www.emtalk.com/tut_1.htm ) I have adapted a existing example to my application. I simulated the patch antenna with HFSS (V10.0), but simulation has shown that the antenna isn't as good as i want. I also built a prototype of this antenna and measured the SWR. It is about 5!
I'll uppload the HFSS-File so you can test it for yourself. For everyone who don't have HFSS here are the dimensions:
f = 866 Mhz
FR4 1.52 mm
Er = 4.4
Patch:
W = 105.41 mm
L = 82.41 mm
Feed: (Have to be 50 Ohm)
W = 2.85 mm
L = 31.35 mm
Waveport:
H = 3 mm
W = 10 mm
What's wrong? Please can someone help me? THX!!!
Regards
Sanchez251