[SOLVED] External laptop wifi antennae

lxs602 · 08-08-2020, 03:18 PM

Hi,

I only get variable or poor wifi signal to my laptop to my room in the house where I live.

The router is in the next room along, on the floor below, about 20 feet away horizontally and about 15 feet away vertically, and I have no access to it.

I wondered if external laptop antennae would help, but the signal strength and quality was actually lower

Picture of set-up:
https://imgur.com/a/VCvUZe3

Standard internal antennae:

Quote:

user@user-pc:~$ iwlist wlan0 scan
Cell 01 - Address: XX:XX:XX:XX:XX:XX
Frequency:2.462 GHz (Channel 11)
Quality=50/70 Signal level=-60 dBm
Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 6 Mb/s; 9 Mb/s; 12 Mb/s; 18 Mb/s; 24 Mb/s; 36 Mb/s; 48 Mb/s; 54 Mb/s
.............
Cell 02 - Address: XX:XX:XX:XX:XX:XX
Frequency:5.22 GHz (Channel 44)
Quality=46/70 Signal level=-64 dBm
Bit Rates:6 Mb/s; 9 Mb/s; 12 Mb/s; 18 Mb/s; 24 Mb/s; 36 Mb/s; 48 Mb/s; 54 Mb/s

External wifi antennae:

Quote:

user@user-pc:~$ iwlist wlan0 scan
Cell 01 - Address: XX:XX:XX:XX:XX:XX
Frequency:2.462 GHz (Channel 11)
Quality=43/70 Signal level=-67 dBm
Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 6 Mb/s 9 Mb/s; 12 Mb/s; 18 Mb/s; 24 Mb/s; 36 Mb/s; 48 Mb/s; 54 Mb/s
..........
Cell 02 - Address: XX:XX:XX:XX:XX:XX
Channel:44
Frequency:5.22 GHz (Channel 44)
Quality=38/70 Signal level=-72 dBm
Bit Rates:6 Mb/s; 9 Mb/s; 12 Mb/s; 18 Mb/s; 24 Mb/s Mb/s; 48 Mb/s; 54 Mb/s

I understand the question above displays a lack of any real knowledge about radio electronics.

I have read though that increased antennae gain is used on routers to broadcast on a flatter plane to increase horizontal range. I don't know how antennae on the receiving end would help or affect signal reception.

Could anyone help explain a little?

What else would you suggest to try - changing the wifi card?

The wireless card is an Intel Centrino Advanced-N 6235 (rev 24). I am using Ubuntu 20.04 on a Toshiba Portege R930.

Thank you

michaelk · 08-08-2020, 03:45 PM

Actually the numbers with the external antenna are good.

The more negative the number the lower the signal strength. -60 dBm is a good reliable signal and I would expect a higher signal for 2.4 GHz band. -64 dBm for the 5 GHz should be a decent signal.

With the internal antenna -67 is ok for 2.4 but not great and -72 dBm for 5 GHz is marginal to unusable.

Is the 15 feet away and no access referencing the internal or the external antenna? 2.4 or 5 GHz?

lxs602 · 08-08-2020, 05:51 PM

Sorry. I mixed up the outputs for external and internal antennae. I have corrected the original post.

I get a poor connection, or failure to connect at all, on both internal or external antennae, on 2.4 or 5 Ghz.

By the distances, I meant the distance the router is away from the laptop. I kept the laptop in the same place each time. The router is in a room that is diagonally below me (I hope that's worded better this time...)

I have no access to it unfortunately, without negotiating with the landlady. Otherwise a long ethernet cable might be the best idea.

kilgoretrout · 08-08-2020, 06:23 PM

Quote:

I have no access to it unfortunately, without negotiating with the landlady. Otherwise a long ethernet cable might be the best idea.

Do you have an ethernet port in your room? If you do, you can get your own wireless access point device and hook it in through your ethernet port.

scasey · 08-08-2020, 07:06 PM

Look into range extender to boost the weak signal. I need one in my home to get to the other end of the house from the router.

michaelk · 08-08-2020, 07:45 PM

Your revised post actually makes more sense. I did not actually look at your posted image until after I posted, the external antennas do not have a proper ground plane which will affect signal quality. The internal antennas may actually have more gain. I am surprised you can not access the router with the internal antennas.

Does Network Manager show your connected to the router or do you never get to that point? Lots of things affect signal strength and what ever the floor is made of could attenuate the signal. Building a directional cantenna and using that to replace your current external antennas might improve signal strength.

https://www.wikihow.com/Make-a-Cantenna

Otherwise you can purchase a USB hi-gain wifi adapter which will help too. Alpha makes some that are supported by linux I don't know which model.

KGIII · 08-08-2020, 07:56 PM

I recently ordered a very inexpensive USB wifi adapter.

https://www.newegg.com/netis-wf2116-...9SIAAFS3W46594

It was like $10, though it now appears to be sold out. Either way, I just looked to see if it was compatible with Linux and ordered it. It not only works out of the box, it gives me great connectivity and throughput. I haven't got a lot of bandwidth (DSL, 'cause I live in a very, very remote area) and I get pretty much the same speeds wireless as I do wired.

In this case, it came with a stand that can be removed and it can be plugged straight into a USB port. I put it on the stand and put the stand on the back of the desk. I'm probably 40' away and this is the results:

Code:

Address: 3C:90:66:49:37:8F
                    Channel:6
                    Frequency:2.437 GHz (Channel 6)
                    Quality=42/70  Signal level=-68 dBm  
                    Encryption key:on
                    ESSID:"Fairpoint378D"
                    Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 18 Mb/s
                              24 Mb/s; 36 Mb/s; 54 Mb/s
                    Bit Rates:6 Mb/s; 9 Mb/s; 12 Mb/s; 48 Mb/s
                    Mode:Master

So, for $10 I resolved the connectivity issue. It might be worth exploring a new device.

lxs602 · 08-26-2020, 12:44 PM

Quote:

Your revised post actually makes more sense. I did not actually look at your posted image until after I posted, the external antennas do not have a proper ground plane which will affect signal quality.

Thank you. I thought there might have been something to do with antennae that I didn't know about. An old metal hard-drive caddy as a ground plane has helped.

I also thought I had already turned off wireless power-saving, which I hadn't checked, so this was also a software issue.

Thank you all for the suggestions and ideas.