 | 1 | initial version |
I think the driver you have is reporting two antennas - so provides both values. For instance, here is the output from the same frame caught by four different adapters on Linux:
tshark -r beacon.pcapng -T fields -e wlan.sa -e radiotap.dbm_antsignal -c 5
00:01:02:03:ef:72 -58
00:01:02:03:ef:72 -60
00:01:02:03:ef:72 -64,-64,-65
00:01:02:03:ef:72 -61,-64,-61
In order, we have here:
For the Intel case, here is what Wireshark shows:
Radiotap Header v0, Length 56
Header revision: 0
Header pad: 0
Header length: 56
Present flags
MAC timestamp: 388880163915
Flags: 0x10
Data Rate: 18.0 Mb/s
Channel frequency: 5745 [A 149]
Channel flags: 0x0140, Orthogonal Frequency-Division Multiplexing (OFDM), 5 GHz spectrum
Antenna signal: -64dBm
RX flags: 0x0000
timestamp information
Antenna signal: -64dBm
Antenna: 0
Antenna signal: -65dBm
Antenna: 1
I am guessing the first one of the three fields is a minimum and then the next two are the specific antenna values. I would think it is driver specific.
Some different adapters, and I know I have some antenna problems (broken/missing):
tshark -i wlan1 -i wlan10 -i wlan11 -i wlan90 -i wlan104 -T fields -e frame.interface_name -e wlan.sa -e radiotap.dbm_antsignal -c 30
wlan10 00:01:02:03:ef:72 -66,-81,-66
wlan10 00:01:02:03:ef:73 -66,-81,-66
wlan10 00:01:02:03:ef:74 -68,-82,-68
wlan11 00:01:02:03:ef:72 -56,-70,-56
wlan11 00:01:02:03:ef:73 -57,-71,-57
wlan11 00:01:02:03:ef:74 -56,-70,-56
<cut>
It looks like the first value is the minimum in this small sample. I get two values from an Atheros chipset:
Atheros Communications, Inc. AR9271 802.11n
wlan1 4a:8a:23:0f:97:b9 -24,-24
With Wireshark showing:
Radiotap Header v0, Length 36
Header revision: 0
Header pad: 0
Header length: 36
Present flags
MAC timestamp: 2018179335135440602
Flags: 0x10
Data Rate: 6.0 Mb/s
Channel frequency: 2462 [BG 11]
Channel flags: 0x00c0, Orthogonal Frequency-Division Multiplexing (OFDM), 2 GHz spectrum
Antenna signal: -79dBm
RX flags: 0x0000
Antenna signal: -79dBm
Antenna: 0
| | 2 | No.2 Revision |
I think the driver you have is reporting two antennas - so provides both values. a minimum and then the actual value. For instance, here is the output from the same frame caught by four different adapters on Linux:
tshark -r beacon.pcapng -T fields -e wlan.sa -e radiotap.dbm_antsignal -c 5
00:01:02:03:ef:72 -58
00:01:02:03:ef:72 -60
00:01:02:03:ef:72 -64,-64,-65
00:01:02:03:ef:72 -61,-64,-61
In order, we have here:
For the Intel case, here is what Wireshark shows:
Radiotap Header v0, Length 56
Header revision: 0
Header pad: 0
Header length: 56
Present flags
MAC timestamp: 388880163915
Flags: 0x10
Data Rate: 18.0 Mb/s
Channel frequency: 5745 [A 149]
Channel flags: 0x0140, Orthogonal Frequency-Division Multiplexing (OFDM), 5 GHz spectrum
Antenna signal: -64dBm
RX flags: 0x0000
timestamp information
Antenna signal: -64dBm
Antenna: 0
Antenna signal: -65dBm
Antenna: 1
I am guessing the first one of the three fields is a minimum and then the next two are the specific antenna values. I would think it is driver specific.
Some different adapters, and I know I have some antenna problems (broken/missing):
tshark -i wlan1 -i wlan10 -i wlan11 -i wlan90 -i wlan104 -T fields -e frame.interface_name -e wlan.sa -e radiotap.dbm_antsignal -c 30
wlan10 00:01:02:03:ef:72 -66,-81,-66
wlan10 00:01:02:03:ef:73 -66,-81,-66
wlan10 00:01:02:03:ef:74 -68,-82,-68
wlan11 00:01:02:03:ef:72 -56,-70,-56
wlan11 00:01:02:03:ef:73 -57,-71,-57
wlan11 00:01:02:03:ef:74 -56,-70,-56
<cut>
It looks like the first value is the minimum in this small sample. I get two values from an Atheros chipset:
Atheros Communications, Inc. AR9271 802.11n
wlan1 4a:8a:23:0f:97:b9 -24,-24
With Wireshark showing:
Radiotap Header v0, Length 36
Header revision: 0
Header pad: 0
Header length: 36
Present flags
MAC timestamp: 2018179335135440602
Flags: 0x10
Data Rate: 6.0 Mb/s
Channel frequency: 2462 [BG 11]
Channel flags: 0x00c0, Orthogonal Frequency-Division Multiplexing (OFDM), 2 GHz spectrum
Antenna signal: -79dBm
RX flags: 0x0000
Antenna signal: -79dBm
Antenna: 0
| | 3 | No.3 Revision |
I think the driver you have is reporting a minimum and then the actual value. For instance, here is the output from the same frame caught by four different adapters on Linux:
tshark -r beacon.pcapng -T fields -e wlan.sa -e radiotap.dbm_antsignal -c 5
00:01:02:03:ef:72 -58
00:01:02:03:ef:72 -60
00:01:02:03:ef:72 -64,-64,-65
00:01:02:03:ef:72 -61,-64,-61
In order, we have here:
For the Intel case, here is what Wireshark shows:
Radiotap Header v0, Length 56
Header revision: 0
Header pad: 0
Header length: 56
Present flags
MAC timestamp: 388880163915
Flags: 0x10
Data Rate: 18.0 Mb/s
Channel frequency: 5745 [A 149]
Channel flags: 0x0140, Orthogonal Frequency-Division Multiplexing (OFDM), 5 GHz spectrum
Antenna signal: -64dBm
RX flags: 0x0000
timestamp information
Antenna signal: -64dBm
Antenna: 0
Antenna signal: -65dBm
Antenna: 1
I am guessing the first one of the three fields is a minimum and then the next two are the specific antenna values. I would think it is driver specific.
Some different adapters, and I know I have some antenna problems (broken/missing):
tshark -i wlan1 -i wlan10 -i wlan11 -i wlan90 -i wlan104 -T fields -e frame.interface_name -e wlan.sa -e radiotap.dbm_antsignal -c 30
wlan10 00:01:02:03:ef:72 -66,-81,-66
wlan10 00:01:02:03:ef:73 -66,-81,-66
wlan10 00:01:02:03:ef:74 -68,-82,-68
wlan11 00:01:02:03:ef:72 -56,-70,-56
wlan11 00:01:02:03:ef:73 -57,-71,-57
wlan11 00:01:02:03:ef:74 -56,-70,-56
<cut>
It looks like the first value is the minimum in this small sample. I get two values from an Atheros chipset:
Atheros Communications, Inc. AR9271 802.11n
wlan1 4a:8a:23:0f:97:b9 00:01:02:03:97:b9 -24,-24
With Wireshark showing:
Radiotap Header v0, Length 36
Header revision: 0
Header pad: 0
Header length: 36
Present flags
MAC timestamp: 2018179335135440602
Flags: 0x10
Data Rate: 6.0 Mb/s
Channel frequency: 2462 [BG 11]
Channel flags: 0x00c0, Orthogonal Frequency-Division Multiplexing (OFDM), 2 GHz spectrum
Antenna signal: -79dBm
RX flags: 0x0000
Antenna signal: -79dBm
Antenna: 0
| | 4 | No.4 Revision |
I think the driver you have is reporting a minimum maximum and then the actual value. For instance, here is the output from the same frame caught by four different adapters on Linux:
tshark -r beacon.pcapng -T fields -e wlan.sa -e radiotap.dbm_antsignal -c 5
00:01:02:03:ef:72 -58
00:01:02:03:ef:72 -60
00:01:02:03:ef:72 -64,-64,-65
00:01:02:03:ef:72 -61,-64,-61
In order, we have here:
For the Intel case, here is what Wireshark shows:
Radiotap Header v0, Length 56
Header revision: 0
Header pad: 0
Header length: 56
Present flags
MAC timestamp: 388880163915
Flags: 0x10
Data Rate: 18.0 Mb/s
Channel frequency: 5745 [A 149]
Channel flags: 0x0140, Orthogonal Frequency-Division Multiplexing (OFDM), 5 GHz spectrum
Antenna signal: -64dBm
RX flags: 0x0000
timestamp information
Antenna signal: -64dBm
Antenna: 0
Antenna signal: -65dBm
Antenna: 1
I am guessing the first one of the three fields is a minimum maximum and then the next two are the specific antenna values. I would think it is driver specific.
Some different adapters, and I know I have some antenna problems (broken/missing):
tshark -i wlan1 -i wlan10 -i wlan11 -i wlan90 -i wlan104 -T fields -e frame.interface_name -e wlan.sa -e radiotap.dbm_antsignal -c 30
wlan10 00:01:02:03:ef:72 -66,-81,-66
wlan10 00:01:02:03:ef:73 -66,-81,-66
wlan10 00:01:02:03:ef:74 -68,-82,-68
wlan11 00:01:02:03:ef:72 -56,-70,-56
wlan11 00:01:02:03:ef:73 -57,-71,-57
wlan11 00:01:02:03:ef:74 -56,-70,-56
<cut>
It looks like the first value is the minimum maximum in this small sample. I get two values from an Atheros chipset:
Atheros Communications, Inc. AR9271 802.11n
wlan1 00:01:02:03:97:b9 -24,-24
With Wireshark showing:
Radiotap Header v0, Length 36
Header revision: 0
Header pad: 0
Header length: 36
Present flags
MAC timestamp: 2018179335135440602
Flags: 0x10
Data Rate: 6.0 Mb/s
Channel frequency: 2462 [BG 11]
Channel flags: 0x00c0, Orthogonal Frequency-Division Multiplexing (OFDM), 2 GHz spectrum
Antenna signal: -79dBm
RX flags: 0x0000
Antenna signal: -79dBm
Antenna: 0
Copyright Wireshark Foundation, 2017-2023 Content on this site is licensed under a Creative Commons Attribution Share Alike 3.0 license.