3

I'm currently in the middle of a somewhat badly planned out install of a intel 2100 mini PCIe wireless adaptor into a HP laptop of some sort. I have a pair of antennae I extracted out of the thinkpad they were in. They were originally against a metal sheet (which would be too much trouble to remove) and at right angles to each other, with the broad part against the metal sheet, and the little lips at right angles, sort of like this

               +-------------------------------+
               |                               |
               +-------------------------------+
               |                               |
               |                               |
               |                               |
               |                               |
               |                               |
               |                               |
               |                               |
               |                               |
               +-------------------------------+


                                                            +------------+---+
                                                            |            |   |
                                                            |            |   |
                                                            |            |   |
                                                            |            |   |
                                                            |            |   |
                                                            |            |   |
                                                            |            |   |
                                                            |            |   |
                                                            |            |   |
                                                            |            |   |
                                                            +------------+---+

enter image description here.

I'm planning on ductaping them to the outside lid of the laptop in question, but I'm trying to understand how the antennae would be best located.Would taping them against the lid (i did say badly planned) be enough, or does the metal sheet also act as an extension of the antennae? or would i be better off chopping off one end, and replacing it with a stick antennae of some sort? Does the main and auxiliary adapters being at right angles have any reason, or is it a space issue?

(and yes, i'm aware that using a USB wireless adaptor is probably simpler. This is more fun)

1 Answer 1

1

First, you should know that the FCC has some rules regarding which antennas can be used with which transceivers. Not that the feds are going to beat down your door, but pairing antennas with transceivers that they are not designed for is generally not a good practice. Be prepared for interference and unstable signals.

Regarding the placement, I would stick with the orientations in which they were originally mounted. The designers put them there to ensure the most possible coverage given all possible scenarios (laptop open, laptop closed, etc.).

The differing angles and locations have to do with the transceiver finding the signal with the least amount of interference. WiFi signals can reflect off of metallic surfaces and create multiple paths to the antenna which results in interference. Having two antennas in slightly different locations and positions allows the radio to select the antenna with the least interference to allow for a cleaner signal and increased range. The fact that laptops are portable and can change orientation makes this a necessity.

The Server Fault Blog recently posted an article regarding the placement of access points which touches on antennas which may be of interest to you.

1
  • apparently the orientations are for handling polarisation. That said, i can't work out a neat solution to mount the darn things, and the reception is (and always has been) crap on that system, so i'm giving up and switching to a USB wireless dongle, unless i want to mess around with the panel antennae
    – Journeyman Geek
    Dec 15, 2011 at 2:28

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .