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Antenna Polarization Mismatch

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Greetings to all here on the forum. I must say I really like the projects that are being done here. I was looking at the 600mW brown bag kit from Black Widow and I had a question about it. It looks like the transmitter antenna is a standard whip antenna (or possibly a helical, I don't know offhand what the internal structure of the antenna is), but it appears to transmit with a horizontal/vertical polarization (depending on which way it's oriented). What I'm wondering is how much more effective the 8dB circularly polarized patch antenna is going to be compared to a standard whip on the reciever. From my undersanding, a polarization mismatch results in about a 3dB loss in signal. So am I correct in assuming that you really get an effective 5dB of gain out of the antenna (compared to 3 db for a standard whip antenna)? It would seem to me that this loss would me mitigated if I got the 14dB linearly polarized antenna instead, since there is no polarization mismatch, there will be no loss (due to polarization).

Am I totally wrong (chances are high that I am :-P )?

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What I'm wondering is how much more effective the 8dB circularly polarized patch antenna is going to be compared to a standard whip on the receiver.
In a perfect world you would gain +6dB, so the range would double. In practice, YMMV. Frankly, the stock omni whips are a poor Rx antenna choice for this application.

From my understanding, a polarization mismatch results in about a 3dB loss in signal.
A linear polarization mismatch is a -20dB hit. If one antenna is circularly polarized, and the other linear, then the average mismatch is -3dB, but is higher when the antennas are not carefully aligned. However, many folks report better overall performance when a circular and linear are used together in our application.

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