Signal strength with WNDR3800

[sigwx]

Hello

Using 1.8.1 and I've noticed that the signal strength I'm seeing 30ft away is noticeably reduced from the Netgear firmware. I used to be able to see signal across the house, now it doesn't get past more than a room or so (no more than 1 wall). I have transmit power set to 'Max', and the channel I'm using is the same in both cases (and fairly clear).

Am I alone seeing this (and maybe its my hardware) or is there something else I should be configuring (via GUI or command line) to increase the signal strength?

Thanks

[Lantis]

What country do you live in?
Your reg domain may be set incorrectly.

try "iw reg get" at a command prompt.

[sigwx]

I'm in the US, and 'iw reg get' says:

country US: DFS-FCC
(2402 - 2472 @ 40), (N/A, 30), (N/A)
(5170 - 5250 @ 80), (N/A, 17), (N/A)
(5250 - 5330 @ 80), (N/A, 23), (0 ms), DFS
(5735 - 5835 @ 80), (N/A, 30), (N/A)
(57240 - 63720 @ 2160), (N/A, 40), (N/A)

[sigwx]

Oh, and I've moved to 1.9.0 (not for this but to see if quotas are working) in case there have been changes in the support for this chipset.

[Lantis]

Run an "iwinfo" and see whether Tx-Power is above 20dBm. If it isn't, then your domain even though it says US is set to the "Worldwide default".
If that is the case, I'd advise trying out 1.9.0 which should allow you to specify this correctly.

If it is higher than 20dBm it is working fine, and in that case what you are experiencing is probably more a performance gap between OEM and Openwrt.

For what it is worth, I also use a WNDR3800 and I noticed very little difference between stock and openwrt.

[sigwx]

Thanks for the info! iwinfo says 28dBm on the 2.4Ghz network, 24dbM on the 5Ghz.

I've manually set the txpower to 29 and 24 respectively, so the only 'odd' thing is the 28, but the off by one won't make that much of a difference.

I've seen reports of the WNDR3700 wifi hardware having issues after around a year, and I'm guessing the WNDR3800 may have the same issues over time. Right now its usable, just not as strong as I remember (and I don't want to go back to factory now that 1.9.0 is working so well with the other features). May have to pick up another one and see if they both have the same behavior.

Thanks again!

[sigwx]

Looking like a hardware issue... found another WNDR3800 to try and its signal (at a setting of 29 and 24) is way better and more like I remember. Thanks again for all the info on how to review the wireless settings!

[Lantis]

No problems mate. I hope you can find a device you are happy with!

[nworbnhoj]

OK so I have a question on my WDR3600. I appear to be limited to 19dBm on both 2.4gHz and 5gHz while TP-Link claims Transmit Power
CE: <20dBm(2.4GHz) <23dBm(5GHz)
FCC: <30dBm
Can I achieve these txpowers?

http://www.tp-link.com/en/products/deta ... ifications

Code: Select all

# iw reg get
country AU: DFS-UNSET
	(2402 - 2482 @ 40), (N/A, 20), (N/A)
	(5170 - 5250 @ 80), (N/A, 17), (N/A)
	(5250 - 5330 @ 80), (N/A, 24), (0 ms), DFS
	(5490 - 5710 @ 160), (N/A, 24), (0 ms), DFS
	(5735 - 5835 @ 80), (N/A, 30), (N/A)

# iwinfo wlan0 txpowerlist
   0 dBm (   1 mW)
   1 dBm (   1 mW)
   2 dBm (   1 mW)
   3 dBm (   1 mW)
   4 dBm (   2 mW)
   5 dBm (   3 mW)
   6 dBm (   3 mW)
   7 dBm (   5 mW)
   8 dBm (   6 mW)
   9 dBm (   7 mW)
  10 dBm (  10 mW)
  11 dBm (  12 mW)
  12 dBm (  15 mW)
  13 dBm (  19 mW)
  14 dBm (  25 mW)
  15 dBm (  31 mW)
  16 dBm (  39 mW)
  17 dBm (  50 mW)
  18 dBm (  63 mW)
* 19 dBm (  79 mW)

# iwinfo
wlan0     ESSID: "abc"
          Access Point: 14:CC:20:5E:D5:2A
          Mode: Master  Channel: 1 (2.412 GHz)
          Tx-Power: 19 dBm  Link Quality: 55/70
          Signal: -55 dBm  Noise: -95 dBm
          Bit Rate: 61.6 MBit/s
          Encryption: WPA2 PSK (CCMP)
          Type: nl80211  HW Mode(s): 802.11bgn
          Hardware: unknown [Generic MAC80211]
          TX power offset: unknown
          Frequency offset: unknown
          Supports VAPs: yes  PHY name: phy0

wlan1     ESSID: "abc"
          Access Point: 14:CC:20:5E:D5:2B
          Mode: Master  Channel: 149 (5.745 GHz)
          Tx-Power: 19 dBm  Link Quality: 51/70
          Signal: -59 dBm  Noise: -95 dBm
          Bit Rate: 150.0 MBit/s
          Encryption: WPA2 PSK (CCMP)
          Type: nl80211  HW Mode(s): 802.11an
          Hardware: 168C:0033 168C:A120 [Atheros AR9580]
          TX power offset: none
          Frequency offset: none
          Supports VAPs: yes  PHY name: phy1

# iw list
Wiphy phy1
	max # scan SSIDs: 4
	max scan IEs length: 2261 bytes
	Retry short limit: 7
	Retry long limit: 4
	Coverage class: 0 (up to 0m)
	Device supports AP-side u-APSD.
	Device supports T-DLS.
	Available Antennas: TX 0x3 RX 0x3
	Configured Antennas: TX 0x3 RX 0x3
	Supported interface modes:
		 * IBSS
		 * managed
		 * AP
		 * AP/VLAN
		 * WDS
		 * monitor
		 * mesh point
		 * P2P-client
		 * P2P-GO
	Band 2:
		Capabilities: 0x11ef
			RX LDPC
			HT20/HT40
			SM Power Save disabled
			RX HT20 SGI
			RX HT40 SGI
			TX STBC
			RX STBC 1-stream
			Max AMSDU length: 3839 bytes
			DSSS/CCK HT40
		Maximum RX AMPDU length 65535 bytes (exponent: 0x003)
		Minimum RX AMPDU time spacing: 8 usec (0x06)
		HT TX/RX MCS rate indexes supported: 0-15
		Frequencies:
			* 5180 MHz [36] (15.0 dBm)
			* 5200 MHz [40] (15.0 dBm)
			* 5220 MHz [44] (15.0 dBm)
			* 5240 MHz [48] (15.0 dBm)
			* 5260 MHz [52] (15.0 dBm) (no IR, radar detection)
			  DFS state: usable (for 94333 sec)
			  DFS CAC time: 60000 ms
			* 5280 MHz [56] (15.0 dBm) (no IR, radar detection)
			  DFS state: usable (for 94333 sec)
			  DFS CAC time: 60000 ms
			* 5300 MHz [60] (15.0 dBm) (no IR, radar detection)
			  DFS state: usable (for 94333 sec)
			  DFS CAC time: 60000 ms
			* 5320 MHz [64] (15.0 dBm) (no IR, radar detection)
			  DFS state: usable (for 94333 sec)
			  DFS CAC time: 60000 ms
			* 5500 MHz [100] (15.0 dBm) (no IR, radar detection)
			  DFS state: usable (for 94333 sec)
			  DFS CAC time: 60000 ms
			* 5520 MHz [104] (19.0 dBm) (no IR, radar detection)
			  DFS state: usable (for 94333 sec)
			  DFS CAC time: 60000 ms
			* 5540 MHz [108] (19.0 dBm) (no IR, radar detection)
			  DFS state: usable (for 94333 sec)
			  DFS CAC time: 60000 ms
			* 5560 MHz [112] (19.0 dBm) (no IR, radar detection)
			  DFS state: usable (for 94333 sec)
			  DFS CAC time: 60000 ms
			* 5580 MHz [116] (19.0 dBm) (no IR, radar detection)
			  DFS state: usable (for 94333 sec)
			  DFS CAC time: 60000 ms
			* 5600 MHz [120] (15.0 dBm) (no IR, radar detection)
			  DFS state: usable (for 94333 sec)
			  DFS CAC time: 60000 ms
			* 5620 MHz [124] (15.0 dBm) (no IR, radar detection)
			  DFS state: usable (for 94333 sec)
			  DFS CAC time: 60000 ms
			* 5640 MHz [128] (15.0 dBm) (no IR, radar detection)
			  DFS state: usable (for 94333 sec)
			  DFS CAC time: 60000 ms
			* 5660 MHz [132] (15.0 dBm) (no IR, radar detection)
			  DFS state: usable (for 94333 sec)
			  DFS CAC time: 60000 ms
			* 5680 MHz [136] (15.0 dBm) (no IR, radar detection)
			  DFS state: usable (for 94333 sec)
			  DFS CAC time: 60000 ms
			* 5700 MHz [140] (15.0 dBm) (no IR, radar detection)
			  DFS state: usable (for 94333 sec)
			  DFS CAC time: 60000 ms
			* 5745 MHz [149] (19.0 dBm)
			* 5765 MHz [153] (19.0 dBm)
			* 5785 MHz [157] (19.0 dBm)
			* 5805 MHz [161] (19.0 dBm)
			* 5825 MHz [165] (19.0 dBm)
	valid interface combinations:
		 * #{ managed } <= 2048, #{ AP, mesh point } <= 8, #{ P2P-client, P2P-GO } <= 1, #{ IBSS } <= 1,
		   total <= 2048, #channels <= 1, STA/AP BI must match
		 * #{ WDS } <= 2048,
		   total <= 2048, #channels <= 1, STA/AP BI must match
	HT Capability overrides:
		 * MCS: ff ff ff ff ff ff ff ff ff ff
		 * maximum A-MSDU length
		 * supported channel width
		 * short GI for 40 MHz
		 * max A-MPDU length exponent
		 * min MPDU start spacing
Wiphy phy0
	max # scan SSIDs: 4
	max scan IEs length: 2257 bytes
	Retry short limit: 7
	Retry long limit: 4
	Coverage class: 0 (up to 0m)
	Device supports AP-side u-APSD.
	Device supports T-DLS.
	Available Antennas: TX 0x3 RX 0x3
	Configured Antennas: TX 0x3 RX 0x3
	Supported interface modes:
		 * IBSS
		 * managed
		 * AP
		 * AP/VLAN
		 * WDS
		 * monitor
		 * mesh point
		 * P2P-client
		 * P2P-GO
	Band 1:
		Capabilities: 0x11ef
			RX LDPC
			HT20/HT40
			SM Power Save disabled
			RX HT20 SGI
			RX HT40 SGI
			TX STBC
			RX STBC 1-stream
			Max AMSDU length: 3839 bytes
			DSSS/CCK HT40
		Maximum RX AMPDU length 65535 bytes (exponent: 0x003)
		Minimum RX AMPDU time spacing: 8 usec (0x06)
		HT TX/RX MCS rate indexes supported: 0-15
		Frequencies:
			* 2412 MHz [1] (19.0 dBm)
			* 2417 MHz [2] (20.0 dBm)
			* 2422 MHz [3] (20.0 dBm)
			* 2427 MHz [4] (20.0 dBm)
			* 2432 MHz [5] (20.0 dBm)
			* 2437 MHz [6] (20.0 dBm)
			* 2442 MHz [7] (20.0 dBm)
			* 2447 MHz [8] (20.0 dBm)
			* 2452 MHz [9] (20.0 dBm)
			* 2457 MHz [10] (20.0 dBm)
			* 2462 MHz [11] (18.0 dBm)
			* 2467 MHz [12] (20.0 dBm)
			* 2472 MHz [13] (20.0 dBm)
			* 2484 MHz [14] (disabled)
	valid interface combinations:
		 * #{ managed } <= 2048, #{ AP, mesh point } <= 8, #{ P2P-client, P2P-GO } <= 1, #{ IBSS } <= 1,
		   total <= 2048, #channels <= 1, STA/AP BI must match
		 * #{ WDS } <= 2048,
		   total <= 2048, #channels <= 1, STA/AP BI must match
	HT Capability overrides:
		 * MCS: ff ff ff ff ff ff ff ff ff ff
		 * maximum A-MSDU length
		 * supported channel width
		 * short GI for 40 MHz
		 * max A-MPDU length exponent
		 * min MPDU start spacing

[Lantis]

"No".

The output of "iw reg get" shows you the australian FCC regulation.

The 2.4GHz one probably makes sense.

The 5GHz one i'd have to know which channel you are on, but you can maybe squeeze a few more dB out of it.


The CE claim is the meet the European specifications and the FCC one to meet FCC regulations.