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Hi – I’ve recently changed my router to one that provides 802.11n and hence can, in theory, work up to 300Mbit/s*. I note the Humax WiFi dongle is also “n”-capable but I don’t see any great increase in speed, either 48 or 56Mbit/s. The connection delay is much reduced however and, it seems, more reliable. My HDR and the router are separated by some distance.
So, I wondered what connection speeds any of you see – does anyone get anywhere near “n”-speeds.
Thanks
*I’m aware depending on the channel used 802.11n might only run at 150Mbit/s.
Have you tried running something like ‘inSSIDer’ to check that you are on a free channel and not overlapping with your neigbours. Things like microwaves and baby monitors can interfear with WiFi. The ‘inSSIDer’ program is availible on Windows and Android so a smart phone is ideal. Some routers are better than others as well so dont expect full speed.
Andy
Thanks for the suggestion of “inSSIDer” which was new to me and is a very useful utility.
I’ve made some progress and my Humax now reports 135Mbit/s mostly and sometimes 121.5. I changed my router over to “802.11n only” and on the Humax changed the Encryption to WPA2-PSK(AES) from WPA2-PSK(TKIP+AES). Research on the dongle suggests its max speed is 150Mbit/s and I presume it has one antenna. [If it had multiple antennae (which is MIMO – Multiple In Multiple Out) then it could go in 150 jumps to 600 in theory].
Using “inSSIDer” it shows the router using two channels, and my laptop now also reports 130 or 65, not sure why there is a difference. Also not sure if the Humax is using both channels – I guess so as it’s 802.11n compliant.
I reckon this is the best I’ll get at present – whether it makes any actual difference to my use (seeing my broadband is only marginally improved now with the new router from 3.4 to 3.8Mbit/s) – we’ll see.
Some further research shows that the 135Mbit/s I’ve achieved is the maximum I can expect with the default 800ns “Guard Interval” used on 802.11n (in fact using channel 7 at 40MHz). The shorter alternative interval of 400ns is likely to achieve the full design speed of 150Mbit/s (again on ch.7). However there are issues to be considered in gaining this 11% increase as detailed in the extract from Wikipedia shown below. So I guess it’s best to stick to 135Mbit/s. (The 121.5Mbit/s I observed was the max on Ch.6 which the router switched to for some reason).
Extract from Wikipedia on Guard Intervals:
“The standard symbol guard interval used in 802.11 OFDM is 0.8 μs. To increase data rate, 802.11n added optional support for a 0.4 μs guard interval. This provides an 11% increase in data rate.
The shorter guard interval results in a higher packet error rate when the delay spread of the channel exceed the guard interval and/or if timing synchronization between the transmitter and receiver is not precise. A scheme could be developed to work out whether a short guard interval would be of benefit to a particular link. To reduce complexity, manufacturers typically only implement a short guard interval as a final rate adaptation step when the device is running at its highest data rate.”
There is overlap in the 11 channels. Only 1, 6 and 11 do not overlap, as you can see from the ‘inSSIDer’ display. I have found it best to select one of these, I use 6 as my neighbors use channel 1 and 11. So insider shows three table like icons with slightly splayed legs and each one is separate and mine is about twice the hight of the other two showing my router gives the strongest signal in my flat.
Andy
Just a quick note to say thank you for this post about inSSIDer. I was struggling to get my HDR FOX T-2 to see my Sky Broadband but realised after reading the advice here that I could log in to my router and change the channel it was broadcasting on (switched from “AUTO” to a free channel). Bingo! It’s now popped up on the Hummy.
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