Impedance of Half-Wave Dipole

How to use openEMS. Discussion on examples, tutorials etc

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noisewarrior
Posts: 1
Joined: Mon 04 Jun 2018, 23:42

Impedance of Half-Wave Dipole

Post by noisewarrior » Wed 06 Jun 2018, 08:59

According to theory the impedance of a half-wave dipole should be 73 + j42.5 Ohm.

My simulation of a 1GHz half-wave dipole seems way off:
dipole2.m
1 GHz Half-Wave Dipole.m
(2.29 KiB) Downloaded 293 times
also posted at https://pastebin.com/VM705AUD

Any suggestions as to where I'm messing up would be appreciated.
Attachments
dipole-impedance.jpg
dipole-impedance.jpg (18.99 KiB) Viewed 2457 times

sajeed.mulla
Posts: 6
Joined: Fri 21 Apr 2017, 16:57

Re: Impedance of Half-Wave Dipole

Post by sajeed.mulla » Wed 25 Jul 2018, 14:03

plz take

L + D = 0.48 x lambda

L is the length of the antenna
D is the diameter of the antenna

you will get exact input impedance as it mentioned in the book.

mzk
Posts: 4
Joined: Fri 26 Apr 2019, 15:20

Re: Impedance of Half-Wave Dipole

Post by mzk » Sun 05 Jul 2020, 14:59

Since this is pretty good example, I'm attaching a slightly modified dipole2.m (not 0.48 ratio tough...).
The commented out lines allow for rectangular shape of the antenna.
MUR changed to PML_8.
S11 is also plotted.
Attachments
dipole2.m
(2.96 KiB) Downloaded 51 times

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