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URGENT!:LOWERING THE Q FACTOR OF THE ANTENNA

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paupau101

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q factor of loop antenna

Hi guys,
I'm designing a small loop antenna and the computed impedance is much greater than
the load impedance. I'm using the L- section network for matching both of the impedances but the technique requires a lower Q. Is there any technique in lowering the Q of small loop antenna?

Pls help.

Tnx.
 

rrumpf

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Is it an option for you to use resistive loading? Otherwise, perhaps literature search broadband loop antennas.

-Tip
 

House_Cat

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To lower the Q for a loop antenna, you need to increase the series resistance or decrease the inductance. If you're using a multi-turn wire loop, decrease the size of the wire to increase the resistance, decrease the diameter of the loop, and/or decrease the number of turns to decrease the inductance.

For a multi-turn loop antenna, Q = 2πfoL/(Rr+RL) where fo=frequency, L=inductance, Rr=radiation resistance, and RL=resistive loss.

If you want the exact equations for inductance, capacitance, etc, look in the ARRL Antenna Book.
 

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