Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronic 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.

Register Log in

impedance matching for dipole antenna @ UHF

Status
Not open for further replies.

sudokubk38

Newbie level 6
Joined
Oct 6, 2010
Messages
14
Helped
1
Reputation
2
Reaction score
1
Trophy points
1,283
Activity points
1,368
please help me:
I design a dipole antenna RFID tag, I want to increase imaginary part to 750 Ohm. thanks very much!
 

vfone

Advanced Member level 5
Joined
Oct 10, 2001
Messages
5,103
Helped
1,517
Reputation
3,035
Reaction score
1,117
Trophy points
1,393
Activity points
32,290
Probably is about a small printed dipole, and you can use a gamma match, which allow tuning the impedance match of the antenna.
 

sudokubk38

Newbie level 6
Joined
Oct 6, 2010
Messages
14
Helped
1
Reputation
2
Reaction score
1
Trophy points
1,283
Activity points
1,368
can you please explain clearly, my friend? impedance value of chip is 36-j750 Ohm. when I use stub to impedance matching but input impedance of antenna just increases about 10+j250 Ohm.
more than, I must obtain broadband from 860-960 MHz. please help me! thanks very much!
 

sudokubk38

Newbie level 6
Joined
Oct 6, 2010
Messages
14
Helped
1
Reputation
2
Reaction score
1
Trophy points
1,283
Activity points
1,368
Thank you very much! I am researching that. By the way, could you please help me about:
"I have a RFID dipole antenna (microstip line), I want to measure input impedance and return loss so that I compare with simulating. But I don't know anyway. Could you please help me?" Thank you in advance!
 

RCinFLA

Advanced Member level 2
Joined
Aug 31, 2010
Messages
569
Helped
185
Reputation
374
Reaction score
182
Trophy points
1,323
Activity points
5,566
Any match stub must run perpendicular to antenna. Any ground plane or components near antenna will effect it. You need a balun to convert to balance line to measure dipole.

Attached is a drawing for an unbalanced to balanced tranformer for making measurements. It can match impedance or transform an S parameter to another impedance plane.
 

Attachments


Status
Not open for further replies.
Toggle Sidebar

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top