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Is Your Router's Transmit Power Juiced?

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You're quoting old posts in which the information has changed, afaik.

And quite a bit at that - I can say that the Broadcom drivers have especially changed with regards to many ways that they can be configured...
 
Interesting article...

Couple of things to consider however...

1) Conducted Path Measurements - you can measure each RF chain, but you need to consider that the impendance match for conducted path is 50 ohm, typical free space matching for EIRP is 37 ohm, so the numbers will change.

2) EIRP is a magical number - what is really important is TRP, and this can only be done in a RF chamber - Rohde&Schwarz has a mini chamber that works well (the DST-200), or one can go for the big-dog, the TS8991

Wireless OEM's spend big money on these items and similar, for example the "StarLab" SATIMO chamber -- which is a gold standard in the RF world.

The FCC's rules here, along with the EU, Anatel, and other regulatory agencies - many follow the guidance of the FCC - but at the same time, there is interpretation of these rules... there are weasel words perhaps, and also loopholes to be exploited -- bending, rather than breaking a given rule.

Most OEM's do have a team that is specifically focused on the Regulatory aspects of the products they develop.

I'm not saying that Asus is in the right or wrong, but this article is only one aspect. This is a rat-hole that perhaps SNB doesn't want to get in to - considering the Netgear-Asus litigation - now that the article is published, can't really un-ring the bell there...

sfx

I thought the limit here in the U.S. is 1000mw ( 1 watt )? I own the RT-N66U and it originally measured -60db on my PC on 5GHz, about 20 feet from the router. I checked and could actually see when I set the power to 200mw - the max. THEN I upgraded the cursed firmware and they appear to have crippled it down in power, to where it doesn't even cover the whole house anymore. I'm looking for an honest higher powered /ac router now.
 
well i have an emf and rf meter that can measure to some estimate, only thing is that the rf meter works up to 3.5 Ghz so i cant check for 5Ghz.

the limit is 1W, however people dont tune their routers properly, they just set the tx power to max and be done with it. For example in my case i just set the tx power on my asus to minimum on 2.4Ghz and maximum on 5Ghz. I set the channel to a range that i see free (part of the reason to not use ISP given hardware is that prosumer APs must be able to use channels that ISP given hardware doesnt use). In my area there is a lot of 5Ghz but all the 5Ghz are using the same channels and apparently despite my AC88U showing many channels i actually only have 3 channels that will give me the full bandwidth, the further away i set the channel from it the less bandwidth i get for wifi.

1W is huge for wifi, if everyone were using their routers at their limit it will be a lot of problems as the unlicensed spectrum would be littered with traffic so even other devices that use little bits of bandwidth but work on the same frequencies will have issues. There are a lot of 2.4Ghz devices around, even bluetooth is 2.4Ghz too.

Im glad that manufacturers are decreasing their tx power however i wish they would be upfront about the numbers in the settings page, showing the mW amount your setting is. Asus for instance just uses a slider for that says either performance or power save when you move it.
 
2.4 GHz band limit is +30 dBm (1W) conducted into the antenna. Maximum allowed radiated power (out of antenna) is +36 dBM (4W). This is for point to multipoint systems.
 
well i have an emf and rf meter that can measure to some estimate, only thing is that the rf meter works up to 3.5 Ghz so i cant check for 5Ghz.

the limit is 1W, however people dont tune their routers properly, they just set the tx power to max and be done with it. For example in my case i just set the tx power on my asus to minimum on 2.4Ghz and maximum on 5Ghz. I set the channel to a range that i see free (part of the reason to not use ISP given hardware is that prosumer APs must be able to use channels that ISP given hardware doesnt use). In my area there is a lot of 5Ghz but all the 5Ghz are using the same channels and apparently despite my AC88U showing many channels i actually only have 3 channels that will give me the full bandwidth, the further away i set the channel from it the less bandwidth i get for wifi.

1W is huge for wifi, if everyone were using their routers at their limit it will be a lot of problems as the unlicensed spectrum would be littered with traffic so even other devices that use little bits of bandwidth but work on the same frequencies will have issues. There are a lot of 2.4Ghz devices around, even bluetooth is 2.4Ghz too.

Im glad that manufacturers are decreasing their tx power however i wish they would be upfront about the numbers in the settings page, showing the mW amount your setting is. Asus for instance just uses a slider for that says either performance or power save when you move it.

That's my problem now. I got the RT-N66U in 2014 and the original firmware showed the power in mw. We have a long house and my bedroom is the furthest, and I switched everything to 5GHz about 2-1/2 years ago, to get out of the neighborhood noise ( west Denver area ). SO I was running the full 200mw - except that I'm not even sure, from reading other posts, that Asus is honest about that. But it was working in the furthest room, which is my bedroom. THEN I made the mistake of updating from the original firmware and it no longer showed the mw - only a slider. The signal dropped by 10db at my PC, which is much closer to the router. It dropped from -60 to -70, which is HUGE - EVEN when maxed out on that slider. So they may have dropped it from 200mw to 15mw! So my bedroom quit working for streaming. I've been trying to watch the same episode of this series, for 2 days, and it keeps rebufering.

On top of that, some forum folks told me about http://www.dslreports.com/speedtest which they said is the best speed test out there. Comcast doesn't want us using it - they want us using theirs, or ones they cherry pick. I just found out the reason. Another thing apparently hurting me is bufferbloat - horrible. In fact I googled it and found out that Comcast has bad problems with it. And that could also explain my streaming TV buffering all the time now.

But the Comcast speed results have also been swinging all over the place, from about 15 megs to 2 megs ( we PAY for 25 meg service! ), and I'm not sure why, on that - whether it's the bufferbloat or what.
But it appears that I need an AC1900 class router now, to fix this, IF it can be fixed without Comcast fixing some of their stuff.

<a href="http://www.dslreports.com/speedtest/17103792">
<img src="http://www.dslreports.com/speedtest/17103792.png"></a>

<a href="http://www.dslreports.com/speedtest/17104048">
<img src="http://www.dslreports.com/speedtest/17104048.png"></a>
 
2.4 GHz band limit is +30 dBm (1W) conducted into the antenna. Maximum allowed radiated power (out of antenna) is +36 dBM (4W). This is for point to multipoint systems.

Ah, ok. Thanks. But the manufacturers are making it hard to find that data now.

I searched for routers that could help with the bufferbloat issue and found this article: http://bluegadgettooth.com/best-dd-wrt-router/

So it seems that dd-wrt routers can solve this, and I'm considering ( Amazon ) the:

Linksys AC1900 Dual Band Open Source WiFi Wireless Router (WRT1900ACS)
and
NETGEAR Nighthawk AC1900 Dual Band Wi-Fi Gigabit Router (R7000) with Open Source
and the
IQrouter – IQRV2 Self-Optimizing router with dual band WiFi (AC1750), which is apparently a new one, with little
feedback yet, but good feedback.

But finding the power ratings on these has been impossible. The AC1900 ones do, however, have beamforming, and simultaneous dual band, which could help immensely in my situation here.
My bedroom is about 40 feet from the router, which sits high on a shelf that I built in the kitchen, through some walls. The "200mw" ( note the quotes ) from the RT-N66U was doing it on 5GHz, but the firmware update blew that. I need honest power now, not hidden crippled power specs from companies that may be covering their butts in lowest common denominator countries that they send the routers to.


 
But finding the power ratings on these has been impossible.

The power levels will vary based on a lot of factors. Beside the country, it will also vary based on the channel, the number of streams, modulation, etc...

It's not just a static value that gets used all the time. That's one of the reasons why those webui settings that claim to allow you to configure a given output level are partly bogus - that value gets overriden by the driver.

It's quite complex. To give you a glimpse as to how complex it is, see this calibration file that's used with an Asus RT-AC68U:

https://raw.githubusercontent.com/R...08/wl/sysdeps/RT-AC88U/clm/src/wlc_clm_data.c

Here's just one single random sample taken from that file:

Code:
 /* Locale A6-57 (A6_57) */
   CHANNEL_SET_1, 0, /* Locale channels (20M), locale flags */
   RESTRICTED_SET_NONE, /* Restricted channels */
       1, /* Public Maxpwr: 1 elt(s) */
   30, RANGE_2G_20M_1_11,    /* 30dBm, 1-11 */
       CLM_DATA_FLAG_WIDTH_20 | CLM_DATA_FLAG_MEAS_COND, /* Maxpower Group Flags */
       4, /*  Locale Maxpwr: 4 elt(s) */
   44, RANGE_2G_20M_1_1,     RATE_SET_20M_146, /* 11.00dBm,   1-1  , (OFDM6-54) */
   68, RANGE_2G_20M_1_11,    RATE_SET_20M_0,   /* 17.00dBm,   1-11 , (DSSS1-11) */
   60, RANGE_2G_20M_2_10,    RATE_SET_20M_146, /* 15.00dBm,   2-10 , (OFDM6-54) */
   44, RANGE_2G_20M_11_11,   RATE_SET_20M_146, /* 11.00dBm,  11-11 , (OFDM6-54) */
 
The power levels will vary based on a lot of factors. Beside the country, it will also vary based on the channel, the number of streams, modulation, etc...

It's not just a static value that gets used all the time. That's one of the reasons why those webui settings that claim to allow you to configure a given output level are partly bogus - that value gets overriden by the driver.

It's quite complex. To give you a glimpse as to how complex it is, see this calibration file that's used with an Asus RT-AC68U:

https://raw.githubusercontent.com/R...08/wl/sysdeps/RT-AC88U/clm/src/wlc_clm_data.c

Here's just one single random sample taken from that file:

Code:
 /* Locale A6-57 (A6_57) */
   CHANNEL_SET_1, 0, /* Locale channels (20M), locale flags */
   RESTRICTED_SET_NONE, /* Restricted channels */
       1, /* Public Maxpwr: 1 elt(s) */
   30, RANGE_2G_20M_1_11,    /* 30dBm, 1-11 */
       CLM_DATA_FLAG_WIDTH_20 | CLM_DATA_FLAG_MEAS_COND, /* Maxpower Group Flags */
       4, /*  Locale Maxpwr: 4 elt(s) */
   44, RANGE_2G_20M_1_1,     RATE_SET_20M_146, /* 11.00dBm,   1-1  , (OFDM6-54) */
   68, RANGE_2G_20M_1_11,    RATE_SET_20M_0,   /* 17.00dBm,   1-11 , (DSSS1-11) */
   60, RANGE_2G_20M_2_10,    RATE_SET_20M_146, /* 15.00dBm,   2-10 , (OFDM6-54) */
   44, RANGE_2G_20M_11_11,   RATE_SET_20M_146, /* 11.00dBm,  11-11 , (OFDM6-54) */

Yeah, ok, but the RT-N66U was working ok in my bedroom, before the firmware update, which I now regret ever making, and then it drastically reduced the power.

But that aside, which of those two routers would those of you here recommend? I need to get this going today, as I cant watch streaming in my room anymore. I'm leaning towards the LinkSys but they both cost the same and both have beamforming and simultaneous dual band, so the deciding factor would be how they handle the bufferbloat and how much power they can put out, which as I said, I have yet to find out.
...
I just tried calling LinkSys sales and tech support and they don't know either.
 
Last edited:
So do any of you have a preference for which of those two routers I mentioned?

Linksys AC1900 Dual Band Open Source WiFi Wireless Router (WRT1900ACS)
or
NETGEAR Nighthawk AC1900 Dual Band Wi-Fi Gigabit Router (R7000) with Open Source
 
The R7000 is mature and has good third party firmware support directly sponsored by Netgear... factory firmware is regularly updated, and very good feature set.

The WRT - very nice hardware, they've been working with DDWRT, and OpenWRT has support for the platform. Linksys doesn't update the WRT's very often...

Hardware-wise, the WRT, but for Software, consider the R7000
 
The R7000 is mature and has good third party firmware support directly sponsored by Netgear... factory firmware is regularly updated, and very good feature set.

The WRT - very nice hardware, they've been working with DDWRT, and OpenWRT has support for the platform. Linksys doesn't update the WRT's very often...

Hardware-wise, the WRT, but for Software, consider the R7000

ARghh. Talk about ambivalence. :)
 

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