Monthly Archives: April 2011

Improve WiFi range and speed

I did some reading to understand what affects WiFi range, but it was hard to find really useful information. Especially, I wanted to know what range I could expect, measured in meters, under different conditions. Well, I did some experiments and here are the results.

The main base station is an Apple Airport Extreme basestation (the one introduced in 2004, without N capability). The range has been extended with WDS using either an Airport Express, or an Asus wl-520gu running Tomato firmware. An iPhone 4 was used to measure range and signal quality (yeah, the best tool for that job).

All experiments are made in a rural area with no other interfering WiFi networks.

Original setup
Originally, the range was extended with the Airport Express, extending the network from one house to another. The distance between the Airports was about 15 meters, going through a few wooden walls. The connection quality was very questionable with lost connections, occationally very bad bandwidth and sometimes the need to restart the network equipment. A mixed B/G network with no encryption was used.

wl-520gu with improved antenna
I got a 32cm long antenna (9dbi) for the wl-520gu. Replacing the Airport Express with this improved wl-520gl made a huge difference. The connection to the Airport Extreme was perfect.

I decided to walk around in the vicinity with my iPhone, and found good reception (3 bars out of 4) about 75 meters away. There were no obstacles between me and and the house where the wl-520gl was located. As soon as I got behind a hill or something, connection was completely lost.

It is worth noting that AirPort Extreme and Tomato can do WDS together (at least without encryption).

wl-520gu with standard antenna
Repating the experiments above with the standard antenna I got much worse results. At 30 meters away, I got worse reception on my iPhone, than I had 75 meters away with the improved antenna. The included standard antennas are not the best ones for your equipment.

Experimenting with transmission power
Tomato allows you to set the WiFi transmission power (range 1-255 mW). Default was 42mW and I raised it to 200mW. So far, I have not noticed any benefits with higher transmission power, and I left it at 50mW. After all, this is the same frequency that microwave ovens use.

G more stable than B
Initially the network was in mixed B/G mode. I thought perhaps the network would be more stable and have better range in the slower B mode. Wrong! It turned out that G mode is not only faster, but also more stable over longer distances, than B.

Directional antennas
I have not experimented with directional antennas. But, my 9dbi antenna gave me quite good range. Obstacles seems to matter much more than distance, at least for shorter distances (up to 75 meters).

On antenna connectors
There are different connectors for WiFi antennas. A very common one is RP-SMA (also called rev-SMA). ASUS uses this connector for their routers. The Linksys WRT54GL has another connector.

Flashing Tomato over OpenWRT on WRT54GL

On Linksys Wrt54GL, flashing Tomato over OpenWRT 10.03 using the web gui works fine. You need to use the tomato.trx image rather than any bin file. When the router is rebooted, it has IP 192.168.1.1, username=root, password=admin.

Update 2015-07-25: I did this from OpenWrt rescue mode, using command line:

# sysupgrade -v -n tomato.trx

After that, I needed to make a hardware reset: start the router up with the reset button (on the back side) pressed. Keep it pressed for about 15-30 seconds (depending on what source you reead), and then restart (unplug and plug).

Ubuntu on EEE1101 (gma500/poulsbo)

After the relative success with with my EEE 701 I decided to give my EEE 1101 a try. First, there are official Ubuntu instructions how to run Ubuntu on a computer with gma500 (poulsbo) graphics chipset. I post the link because it is surprisingly hard to find it using google. Note that they updated that page just about an hour before I write this.

Natty (Ubuntu 11.04)
First I gave Natty a try (the Ubuntu page was not so discouraging a few days ago). It did not work at all, and since it is not supposed to work, I am not going to explain what I went through.

Maverick (Ubuntu 10.10)
Maverick installs without much problem on the EEE 1101, using a slow VESA-mode (or something) at 1024×768. As soon as I was done with the installation I upgraded (apt-get update, apt-get upgrade) and then followed the instructions. The first command (add-apt-repository) gave some GPG-key complains, but I found out it was ok to proceed anyways. The other commands went all fine. I rebooted, and everything was fine.

Unity
I decided to try Unity on this machine with Maverick. I found installation instructions for Unity and followed them. Unity did not work at all. The “dock” did not render properly. The “menu” did not render properly. The computer felt very slow. I gave up.

External display
I use this netbook at work, and it is common that I connect it to a projector during a meeting. This has before stopped me from running Ubuntu on it. Well, I found out that:

  • Mirrored display (same output on both screens) is not possible to choose at all
  • Side-by-side requires changing X virtual screen size, this destroys performance completely
  • Turning external display ON, and laptop display OFF, then clicking Apply, works well (at least for 1024×768).

Having your laptop display black, and the external display working, can be worthless, useful, or perfect, depending on situation. The Gnome monitor application is not really designed to do this kind of switch only, so it is a little cumbersome, but it works.

Flash performance
YouTube video performance is bad. 240-resolution flows. At higher resolution, and full screen, the jerkiness and lost frames make it unpleasant to view. Facebook games like CityVille are painfully slow to play. To be fair, I think this is very slow in Windows too, on this computer. (I will double check some day)

Ubuntu 11.04 Beta 1 on Eee 701

I have two Asus EEE PCs, probably the two worst ones they made. I have an EEE1101, which comes with the horrible GMA500.

And I have an EEE701. It was a nice idea, at a nice price, but the actual machine sucks. Keyboard on the brink of unusable and poor battery life. The Celeron 900HMz at 630MHz does not help much. But the worst thing is not the 7-inch 800×480 display – it is the lack of OS/Window Manager that makes good use of it.

Yesterday I came across this review of Ubuntu 11.04 Beta 1 on TheRegister. Can it really be that bad? Can it be something for my EEE701.

Well, I am writing this post on my EEE701 Ubuntu 11.04 right now – that is a good start. Installation went smooth (after I failed to boot the EEE from a 4GB SDHC card).

Most things work out of the box: Wireless network, Video, Webcam, Audio (via headset, not loudspeakers – perhaps my Eee is old and broken), volume buttons and display light buttons. Booting time is about a minute.

I removed a few Items from the Launcher/Dock because with 480 pixels you need to prioritize. I use firefox mostly in full screen mode (F11), and occationally I have to use Alt-F7 to move windows around.

The computer feels a bit slow, but useful. CPU at 630MHz (not overclocked – should maybe look into that). I have 1GB RAM and no swap partition.

Flash videos on YouTube are enjoyable, but not perfect.

Do I hesitate about updating my other computers from Ubuntu 10.10 to 11.04? Absolutely (well, Gnome is still there).

Do I think that Ubuntu 11.04 is the best OS for my EEE701? Yes – I think so.

Would EEE701 + Ubuntu 11.04 impress on anyone? No – I dont think so.

The review in The Register focuses on that Unity is nice, but it does much less than Gnome. Well, for my netbook that is not so bad. And I am used to falling back to the command line a lot anyway.

Nikon P7000 now supported

The Nikon P7000 camera is now supported by iPhoto. It also works in Shotwell 0.9.0 in Ubuntu 10.10. The NRW Raw files I mean.