1400 Wireless N Has 2 antennas?

So, when I disassembled my 1520, there were 3 antennas that connected the intel 4965 agn (silver, white, black) I disassembled my 1400 today, and there's only 2 antennas connected to the BCM94321mc (black and white) The silver one is disconnected. I thought wirless N needed 3 antennas? Anyone have a second to clear this up?

 

1400 does have three antennas.

 

Maybe it is something like the situation on the M1330.
On M1330 there is only a third antenna for the 'n' wireless if you took the model without the thin LED backlit screen.

Today's 'n' wireless cards only use a third antenna for antenna diversity. i.e. they take a look at the signals and ignore the antenna with the worst signal. So they don't actually use 3 antennas. Depending on where the antennas are run in the notebook it may be that one of the three is predictably always going to be turned off by the wireless card - in which point there is no point in connecting it in the first place. Also, I think as Dell start to prepare models for wireless USB they may be re-allocating an antenna for that.

 

They should connect the third connector to an outside connector for an external antenna. Then it will automatically switch to external if it's connected and working properly.

 

I have both the 4965 and Dell-Broadcom-N. The Dell only has two antenna contacts, the 4965 has three.

The 1420 has three antenna wires (grey, black, white).

 

That kind of lame. Id assume the Intel card is a little better since they actually make use of that third antenna. Too bad the Vostro 1400 only has the Dell N option.

sOnIc

 

eh, just checked it out and they added the Intel option back. Its actually 30 dollars more..

 

So, if anyone searches and pulls up this thread, here is some reading material. Via google, there's not much explanation whether wireless n needs three antennas or not.

http://www.edn.com/article/CA6470826.html

Basically, for MIMO, your card needs atleast 2 antennas, hence multiple in, multiple out. 3 antennas is better though, because then there is 3 streams in and out of your wireless connection, provided the router itself has 3 antennas. Again, the third antenna is not required, but theoretically should increase speed and efficiency since youre providing a third stream of data. We all know though that reality and theory are not equal.

sOnIc