How to do impedance matching on a helical antenna?

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Albert Manfredi

This article should explain what you need.

https://antenna-theory.com/antennas/travelling/helix.php

Also, here's a calculator that's already been figured out.

https://www.daycounter.com/Calculators/Helical-Antenna-Design-Calculator.phtml

Ziad Sobih

Please look at my book

The American University Laboratories For Electrical Engineering Part 2

The American University Laboratories For Electrical Engineering Part 3

I hope you like it.

Malcolm White

Matching with a resistor always wastes more power in the resisitor than the power that would have been reflected, so unless the reflected power causes a problem somewhere else and there is no other way of stopping it, don't use a resistor.

Martin Lema

Dear Meenakshi

I agree with Malcom. Never use resistor for impedance matching. Of course the measurement shows "perfect" impedance, but the antenna doesn´t radiates at all.I don´t know what type of helical antenna are you talking about. If it is a NMHA (diameter much less than wavelengh) the correct groundplane can help to increase the radiation resistance (these antennas has very very low radiation reistance, near few ohms). If you are talking about axial mode or conical mode ( each turn equal or greater than a wavelengh) probably a tap conection will help in impedance matching. A very useful tool is the 4NEC2. It is free for education and personal use. It is not a proffesional electromagnetic simulator, but helps a lot in all these stuff.

Best regards

Smrity Dwivedi

Hello,

I do agree with Prof. Lema and Prof. White, that never use resistance for impedance matching. Actually, mismatch loss can be calculated using commercial software, so it will be easy to analyze the antenna matching impedance.

Few references are attached.

Thanks,