I am trying to analyze the up-link Wireless traffic generated by my Sony Ericsson phone and captured by my D-Link router, on which I installed the DD-WRT firmware. To do this, first I log in the router and enable the prism0 interface by typing the command:

wl -i eth1 monitor 1

and then I start to capture the packets by typing:

tcpdump -i prism0 ether src xx:xx:xx:xx:xx:xx -s0 -w /tmp/smbshare/sony_ericsson_test.pcap

where xx:xx:xx:xx:xx:xx is the MAC address of my Sony Ericsson phone. After a while I transfer the sony_ericsson_test.pcap file to my computer and open it with Wireshark program. In order to display the RSSI values I follow this procedure: Edit -> Preferences... -> Columns -> Press "Add" button -> As "Field type" I choose "IEEE 802.11 RSSI" and finally I choose name "Power" and click on "Apply" button. The problem is that the column "Power" is empty with no RSSI values.

Does Anyone has a clue on why are RSSI values not displayed? Maybe I am missing a passage.

Looking forward to hearing from anyone of you!

Thanks in advance for your help!