q factor of loop antenna
时间：03-31
整理：3721RD
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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.
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.
Is it an option for you to use resistive loading? Otherwise, perhaps literature search broadband loop antennas.
-Tip
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.