G+_Brad Flubacher Posted October 30, 2015 Share Posted October 30, 2015 Regarding extending wireless to the RC park- I no not believe that the benefit of adding a directional antenna would result in any asymmetry in ability to transmit or receive. The (simplified) link budget is Tx power + Tx Loss + Tx gain + Pathloss + Rx gain + Rx loss. Assuming both endpoints transmit with the same power, a boost in either value for antenna gain will benefit both. The numbers of the question don't change their value, just their location in the equation! Thoughts? Link to comment Share on other sites More sharing options...
G+_Carlton Dodd Posted October 30, 2015 Share Posted October 30, 2015 Sounds right to me. This is why putting better antennae on my transmitter will let me fly my multi-rotor farther, without changing anything on the multi-rotor. Link to comment Share on other sites More sharing options...
G+_Eddie Foy Posted October 30, 2015 Share Posted October 30, 2015 the higher the gain the more narrow the field. No antenna will, by itself, amplify. They only rob power from one area/direction to give to another, Link to comment Share on other sites More sharing options...
G+_Brad Flubacher Posted October 30, 2015 Author Share Posted October 30, 2015 Eddie Foy Bubbles (love it), we should add the fact that two antennas can have differing effective radiated power (sum total of power radiated in all directions). While an antenna doesn't ever amplify, antenna "A" with an effective radiated power "P1", antenna B- "P2": P1 doesn't equal P2 as I understand it. Even though the power is robbed from one direction and given to another, as you put it, the total radiated power will be different. Having said all of that, in the static scenario I meant to address initially, none of this factors in at all. Link to comment Share on other sites More sharing options...
G+_Travis Hershberger Posted October 30, 2015 Share Posted October 30, 2015 Wayne Hobbins Feeling like we need an segment on "This is how antennas work?" Link to comment Share on other sites More sharing options...
G+_Brad Flubacher Posted October 30, 2015 Author Share Posted October 30, 2015 Sorry.. I feel squeezed into this little text box. My love for antennas can't be contained Link to comment Share on other sites More sharing options...
G+_Eddie Foy Posted October 30, 2015 Share Posted October 30, 2015 Bradley Flubacher which is why making your own antenna without an antenna analyzer (or spectrum analyzer with tracking generator fed through a directional coupler) to measure and tune the SWR is asking for trouble. (for Tx., Rx would just be poor performance). The antenna made to the mathematical #'s won't ever be perfect in real world. Too high a SWR damages the finals of the RF amplifier. They really don't like to see RF come back into them. Link to comment Share on other sites More sharing options...
G+_Ben Reese Posted October 30, 2015 Share Posted October 30, 2015 Here's the Hak5 explanation of antennas: Link to comment Share on other sites More sharing options...
G+_Brad Flubacher Posted October 31, 2015 Author Share Posted October 31, 2015 Ben Reese Unfortunately that video contains a lot of inaccuracies. Afraid he was out of his depth. Link to comment Share on other sites More sharing options...
G+_Jason Marsh Posted October 31, 2015 Share Posted October 31, 2015 I was arguing with Fr. Robert Ballecer, SJ on the TV while watching the episode, but somehow he couldn't hear me :) No matter what topic you discuss, unless you're an expert in the field there will be those knowledgeable enough about the given topic to break your balls about everything you said. But, yeah, I'm with you Bradley Flubacher . You absolutely can improve wireless performance by making improvements on only one end of a link. Link to comment Share on other sites More sharing options...
G+_Jason Marsh Posted October 31, 2015 Share Posted October 31, 2015 Eddie Foy if you have such equipment, I'd send you my janky, uber-ghetto cantenna to measure it's properties. I'm sure it's horrible on a meter, but the thing works like a champ. Dumb luck, I'm sure; but I only hook it to old wrt54g's that I picked up here and there for next to nothing. Link to comment Share on other sites More sharing options...
Recommended Posts