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Antenna Selection (ASEL) Capabilities in HT control field

0

ASEL is an 802.11n MIMO technique which is cheaper to implement compared with beamforming. Details of the technique can be found here:

http://www.merl.com/publications/docs/TR2006-057.pdf

I want to be able to see if units do indeed employ this feature.

ASEL capability is defined in the "ASEL control field" of the "HT control field" in the MAC header

The exact location of the frame is here: https://books.google.com/books?id=0GwFrd90G3kC&pg=PA413&lpg=PA413&dq=asel+802.11+ht+control+field&source=bl&ots=0SPEGKQcUz&sig=TNEWYeCGCQm617D4HfNijYQHiA4&hl=en&sa=X&ved=0CDIQ6AEwA2oVChMIypvdibbmxgIVEFGICh0JkA4z#v=onepage&q=asel%20802.11%20ht%20control%20field&f=false

I have tried using the following filter using Wireshark with no success: wlan_mgt.asel.capable https://www.wireshark.org/docs/dfref/w/wlan_mgt.html

Can someone please explain to me what I'm doing wrong or how I can go about finding the correct way of filtering packets to find this field?

Many thanks in advance!

B

asked 18 Jul '15, 22:53

John%20Snow's gravatar image

John Snow
6112
accept rate: 0%


2 Answers:

0

wlan_mgt.asel.capable == 1

That field name is a boolean type. You must provide whether it exists (1) or does not exist (0).

Here is a tip for determining applicable values for field names in wireshark:

  1. In the Packet Details pane, find the value that you would like to filter
  2. Right click on the field and select "Prepare a Filter" and then choose Selected
  3. In the filter toolbar, you should see the desired filter. Then change the value accordingly

answered 20 Jul '15, 17:30

Amato_C's gravatar image

Amato_C
1.1k142032
accept rate: 14%

0

In the HT Control field:

ASEL command: wlan_mgt.htc.lac.asel.command

ASEL data: wlan_mgt.htc.lac.asel.data

answered 20 Jul '15, 20:19

Guy%20Harris's gravatar image

Guy Harris ♦♦
17.4k335196
accept rate: 19%