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I bought Linksys WiFi Access Point WAP610N.

I had a great access point already..but it didn't support N so I decided to upgrade.

Now I configured it somehow and set it to use 5Ghz frequence in N-only mode.

I expected that my hotspot would be accessible from a broader area but in reality...my older b/g access point (actually router) supported longer distance...

(the main goal is "range" and not the speed!) I am ready even for 1Mps if it worked at longer distance)

What am I doing wrong?

I set channel width to 40Mhz only (another option is 20Mhz only) The wide channel set to: 46 (other options: Auto (DFS), 38, 46)

Standard channel set to: 48 - 5.240 Ghz (another option is: 44 - 5.220 Ghz)

I just want to be able to access my hotstpot from a little bit longer distance (5 meters). I am not expecting some really long area but..right now it's shorter than my older Linksys WRT54G b/g)

Other options are here:

AP Isolation set to disabled.

Basic rate is set to Default (another option is: All)

N Transmission Rate is set to: auto and it has a lot of other options starting with mcs0 to mcs15 with Mbps ratings

Transmission power is set to 100% (50%, 25%, 12%)

CTS Protection Mode is set to: Auto (another option is: Disabled)

Beacon interval is 100 (range from 20 to 1000)

DTIM Interval is: 1 (range 1-255)

RTS Threshold 2347 (range 0-2347)

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You shouldn't have any trouble accessing either router from 5 meters away. For the best signal reception, make sure that the path between your laptop and router is as clear as possible. You may also need to change the orientation of the antennas. –  Joe Internet Jul 21 '11 at 13:16
    
i meant longer for five meters distance from current range and not the overall distance. sorry for that. –  bakytn Jul 21 '11 at 19:35

2 Answers 2

up vote 1 down vote accepted

Don't use N-only mode. Set it back to Mixed. N-only mode sacrifices range for speed. The older modulation schemes from the A/B/G days sometimes work better at range, so it's good to leave them enabled so that even N clients can use them when they're the best choice.

Also, I'd be surprised if your router really has a 40MHz-only mode, as the IEEE 802.11n standard does not provide for that. The standard only provides for 20MHz-only and 20/40 modes, but no 40MHz-only mode. If you router really does have a 40MHz-only mode and you've set it that way, change it to 20/40 so that devices on your network can choose 20 or 40MHz transmissions as it suits them.

KCotreau is right that all else being equal, signals in 5GHz don't go as far as signals in 2.4GHz. However, due to varying regulatory agency rules for different frequency bands, and varying radio designs, some APs may well be able to transmit at higher power in 5GHz to make up the difference. BUT, the specs on your Linksys WAP610N say it has higher power, higher sensitivity, and even a slightly higher-gain antenna in 2.4GHz.

Look at this table from your User Guide:

RF Power (EIRP) in dBm
802.11a: 15 dBm (typical) @ 54Mbps
802.11b: 18 dBm (typical) @ 11 Mbps
802.11g: 16 dBm (typical) @ 54 Mbps
802.11n: 12 dBm (typical) @ 130 Mbps (HT20),
                            270 Mbps (HT40)

Receive Sensitivity in dBm
802.11a: -72 dBm (typical) @ 54 Mbps
802.11b: -85 dBm (typical) @ 11 Mbps
802.11g: -73 dBm (typical) @ 54 Mbps
802.11n: -70 dBm (typical) @ MCS15/2.4 GHz,
         -69 dBm (typical) @ MCS15/5.0 GHz

Antenna Gain in dBi
2.4 GHz: 1.58
  5 GHz: 1.45

Note that in decibels, a gain of 3 dB is a doubling of power, so this is saying that it puts out 4x as much power when transmitting at 802.11b rates than it does when transmitting at 802.11n rates. (Too bad it doesn't say which band those N rate power levels are for, so I guess we'll just have to assume the same number applies to either band, which seems unlikely, but whatever.) It's also saying that it can successfully receive B-rate transmissions that come in at just 1/32nd the power of the quietest N-rate transmission it can receive.

So it looks like, for this device, you'd have a huge range advantage by going back to the 2.4GHz band and re-enabling the legacy rates (just leave the "Network Mode (2.4GHz)" set to "Mixed"). Also leave the "Transmission Rates" set to "Auto".

Be sure to pick a clean channel (or leave channel selection on Auto and hope your AP does a good job of picking a clean channel).

Also, when doing 802.11n in the 2.4GHz band, you should consider using HT20 (20MHz-wide channels) only, not 20/40 or 40-only. This is because the 2.4GHz band is small crowded, and the channels overlap. If you use 40MHz wide channels here, you're using up 2/3rds of the band, and that doesn't leave much room for coexistence with other networks, or Bluetooth devices, or 2.4GHz cordless phones or baby monitors or whatever. It means you're only going to get 130-144 megabit per second signaling instead of the 270-300 megabit per second signaling your N gear could be capable of, but it might make everything work out better anyway by reducing interference.

P.S. I just looked some more at the US English user guide for that box and oh boy is it terrible. It's clear the writer doesn't know the 802.11 concepts he's trying to write about. But then again, I don't think the web GUI engineers knew what they were doing either, because I can't believe the product provides a non-standard 40MHz-only mode without providing a standard 20/40 mode. I'll bet that what the User Guide and web GUI call 40MHz-only is actually 20/40 if you look at it with a sniffer. It's also weird that they use the channel number of the center frequency of the wide channels. Almost everyone else in the industry tells you the channel number of your control channel, then says +1 or -1 to tell you if your extension channel is above or below your control channel.

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Thank you for the comprehensive response! Will do other tests later today. BTW, it allows to choose channel numbers if I select 2.4Ghz mode (not 5Ghz). So the interfaces differ. I have to test and test in order to find optimal results. The good thing is that there are no any other AP's 1mile around nor we use BlueTooth widely. I can say that interferences are not the case. –  bakytn Jul 21 '11 at 12:39
    
ok, I called their support and they helped. I used 40mhz only in 2.4Ghz mode. AP now supports a little bit broader distance..but I expected more. However I do understand that I really own a powerful hardware..possibly that's just a limit. But in their support, they refused to help me configure in Advanced settings tab saying that it might be dangerous –  bakytn Aug 9 '11 at 11:13

Actually in radio theory, range decreases the higher you go in the spectrum, but you gain clarity. That is why submarines use very low frequency (VLF) to transmit long distances.

http://en.wikipedia.org/wiki/Very_low_frequency

Despite that, I still like the upper ranges since they seem to be less susceptible to interference, like from most cordless phones in the 2.4 GHz range.

This link deals with phones, but the radio theory is the same.

http://www.epinions.com/content_1277730948 (go down to the section "What's with the new 5.8GHz?")

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hey! this is extremely interesting! (still fighting with my AP) –  bakytn Jul 20 '11 at 14:44
    
I had the same problem using the A-band a long time ago. It just did not travel far enough. In another life, I used to work with radios in the service. –  KCotreau Jul 20 '11 at 14:45
    
used lower frequence..no result. :( –  bakytn Jul 20 '11 at 15:06
    
Do you know what is N Transmission rate? –  bakytn Jul 20 '11 at 15:06
    
@bakytn Here is a nice list of most transmission rates: en.wikipedia.org/wiki/List_of_device_bit_rates –  KCotreau Jul 20 '11 at 15:16

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