Posted: Fri May 01, 2020 11:57 Post subject: WRt32x Antenna question: Antenna Gain
Hello,
I purchased from Amazon TECHTOO 9dBi Omni WiFi Antenna with RP-SMA Connector for Wireless Network. Should I leave the antenna gain section alone or do I need to make adjustments I know the transmit power we cannot change because FCC. How about the Antenna Gain that has default 0 in it. Also if anyone has the best settings for Wirless to optimize. thank youu
Joined: 04 Aug 2018 Posts: 1444 Location: Appalachian mountains, USA
Posted: Sat May 02, 2020 19:23 Post subject: Re: WRt32x Attena question Antenna Gain
weaklinks wrote:
Hello,
I purchased from Amazon TECHTOO 9dBi Omni WiFi Antenna with RP-SMA Connector for Wireless Network. Should I leave the antenna gain section alone or do I need to make adjustments I know the transmit power we cannot change because FCC. How about the Antenna Gain that has default 0 in it. Also if anyone has the best settings for Wirless to optimize. thank youu
For the last dozen or so years, most of my professional life has been as an antenna engineer, so I'll take a stab at this one. I can't actually imagine why dd-wrt has a setting for this. It's a matter of antenna design. Nothing dd-wrt can really do about it. (Or is there something going on here that is seriously nonobvious. Anyone?)
BTW, an antenna is not an amplifier, so it cannot produce more transmit power. All it can do is redistribute the power given to it by the transmitter across the sphere of possible directions of radiation. The "i" in "dBi" is for "isotropic." An isotropic antenna is hypothetical thing that distributes the power uniformly across all those directions, and an antenna with 9 dBi gain is producing, in some direction or directions of interest, a power density 9 dB above what an isotropic antenna would produce. That's a power ratio of roughly 8:1. The simplest (not terribly realistic, but if we want simple) model of what's happening is that power is being radiated at equal levels across 1/8 of the sphere and not radiated at all across the other 7/8. So imagine a sphere with the top and bottom chopped off so that only 1/8 of the original surface remains, now in a sort of donut shape. That's your omni pattern.
The takeaway is that you get your gain in one direction by not radiating it somewhere else. In this case, if everything is on one floor of the house, things may be great. If a client is upstairs two levels above the router, it may not fall into the donut and so may receive a significantly lower power level (not actually zero, as real antennas don't go from all to nothing in an abrupt way). So if you need decent coverage in lots of directions that include directions significantly upward and downward, be careful about going with a high-gain antenna. High gain in one direction means low gain (negative number of dBi) in another direction, and a really high-gain omni antenna has a really flat donut. It's not friendly towards clients up or down from the horizontal plane (assuming the antenna is oriented vertically). _________________ 2x Netgear XR500 and 3x Linksys WRT1900ACSv2 on 53544: VLANs, VAPs, NAS, station mode, OpenVPN client (AirVPN), wireguard server (AirVPN port forward) and clients (AzireVPN, AirVPN, private), 3 DNSCrypt providers via VPN.
Joined: 10 Nov 2018 Posts: 350 Location: South Carolina
Posted: Sat May 02, 2020 23:31 Post subject: Large gain router antenna
Folks, I think the answers above are spot on technically, theory seems sound. I personally have been a licensed ham radio operator since the 70s, so I'm not a stranger to antenna structures and theory, but in no way an “expert”. I can post my personal experience taking the stock router antennas, and replacing them with the larger (taller) higher gain models. Leaving the router where it was (in my case), noticed no “notable” signal change or range increase. As always, your personal mileage may vary. But I have serious reservations, that you will see a performance increase worth of the cost of the larger antennas.
Joined: 04 Aug 2018 Posts: 1444 Location: Appalachian mountains, USA
Posted: Sun May 03, 2020 12:30 Post subject:
Per Yngve Berg wrote:
Entering a value in antenna gain will only lower the transmitted power.
So there you have it, folks. It's a regulatory thing. Law limits the radiated power, so entering a gain figure matching that of the actual antenna(s) corresponds not to increasing power to clients in the favored directions but to decreasing power to clients in the nonfavored directions. If you instead leave the antenna-gain setting at 0 dBi while using a higher-gain antenna, you'll be doing a little of both, but unless you've set Tx power below the legal limit, you'll be doing it illegally. (Thanks, Per.) _________________ 2x Netgear XR500 and 3x Linksys WRT1900ACSv2 on 53544: VLANs, VAPs, NAS, station mode, OpenVPN client (AirVPN), wireguard server (AirVPN port forward) and clients (AzireVPN, AirVPN, private), 3 DNSCrypt providers via VPN.
Joined: 08 May 2018 Posts: 14125 Location: Texas, USA
Posted: Wed May 06, 2020 2:13 Post subject:
I think the strongest antennas you can get anymore through any vendor is 20 or 21db gain, if I am not mistaken. The mesh-dish directional antennas used around 20 years ago for the ~1 mile and ~6.2 mile links some folks I know set up were 24db gain, and I think the hardware was Orinoco. I just don't remember if it was Linux 2.2 or 2.4... I've slept since then
Pacwireless made these, they are now defunct, and the company that took over, Laird, no longer makes these AFAIK, but this is basically what they used:
holy cow my home is small and I just have one small problem.
My bedroom on the footboard of the bed I got signal and by the headboard i don't the TV is to the left and EcoDot honestly I a missing what 5 feet, are there settings that I can adjust?
Thank you i have done what you suggestion. I will let you know the outcome thank you again
Hello,
Quick update since the change, as far as 5g the settings you requested are doing really well, I am able to have decent speeds in my bed room. The 2.4 has been having issues. when i try to even do a speed test it takes a long time to start and my speeds are sooo bad when they do.
Joined: 04 Aug 2018 Posts: 1444 Location: Appalachian mountains, USA
Posted: Thu May 14, 2020 16:49 Post subject:
Some of those settings, like TurboQAM and NG-Mixed, are specific to 2.4G wifi. _________________ 2x Netgear XR500 and 3x Linksys WRT1900ACSv2 on 53544: VLANs, VAPs, NAS, station mode, OpenVPN client (AirVPN), wireguard server (AirVPN port forward) and clients (AzireVPN, AirVPN, private), 3 DNSCrypt providers via VPN.