What is the difference between -ve and +ve Gain of antenna. And which is better.

 

What is the difference between -ve and +ve Gain of antenna. And which is better.

You may have conflated two different things. Gain of an antenna is measured in dB with respect to a reference such as an isotropic radiator or a dipole.
-ve and +ve refer to the negative and positive supply voltages in a power supply which might be used in an amplifier circuit.

 

You may have conflated two different things. Gain of an antenna is measured in dB with respect to a reference such as an isotropic radiator or a dipole.
-ve and +ve refer to the negative and positive supply voltages in a power supply which might be used in an amplifier circuit.

Hi Papabravo
your 1st statement is correct but 2nd statement is wrong. antenna is there with both +ve and -ve gain.please study the below antenna having Part No. HA.21.A and FR05-S1-R-0-105.
but i am unable to understand about these two gains

 

Negative gain is the same as a loss. So if your test antenna had a +3db gain with respect to an isotropic antenna then you could say that the isotropic antenna had a -3db gain with respect to the test antenna. NOTE an isotropic antenna is not a physical antenna. It is a concept antenna where the power is evenly distributed over the surface of a sphere.

Les.

 

Hi Papabravo
your 1st statement is correct but 2nd statement is wrong. antenna is there with both +ve and -ve gain.please study the below antenna having Part No. HA.21.A and FR05-S1-R-0-105.
but i am unable to understand about these two gains

There is no antenna below. Did you meant to include a link? The part number is great, but it is of little help without a manufacturer.
The second statement is also correct , regardless of whether it is used in your context which you did not explain or provide a link to.