Antenna

Bit Number
11
Structure
u8
Unit
antenna index

Unitless indication of the Rx/Tx antenna for this packet. The first antenna is antenna 0.

Antenna noise

Bit Number
6
Structure
u8
Unit
dB

RF noise power at the antenna, decibel difference from an arbitrary, fixed reference.

Antenna signal

Bit Number
5
Structure
u8
Unit
dB

RF signal power at the antenna, decibel difference from an arbitrary, fixed reference.

Channel

Bit Number
3
Structure
u16 frequency, u16 flags
Required Alignment
2
Units
MHz, bitmap

Tx/Rx frequency in MHz, followed by flags.

Currently, the following flags are defined:

Mask

Meaning

0x0010

Turbo Channel

0x0020

CCK channel

0x0040

OFDM channel

0x0080

2 GHz spectrum channel

0x0100

5 GHz spectrum channel

0x0200

Only passive scan allowed

0x0400

Dynamic CCK-OFDM channel

0x0800

GFSK channel (FHSS PHY)

FHSS

Bit Number
4
Structure
u8 hop set, u8 hop pattern
Units
??

The hop set and pattern for frequency-hopping radios.

Flags

Bit Number
1
Structure
u8 flags
Unit
bitmap

Properties of transmitted and received frames.

Currently, the following flags are defined:

Mask

Meaning

0x01

sent/received during CFP

0x02

sent/received with short preamble

0x04

sent/received with WEP encryption

0x08

sent/received with fragmentation

0x10

frame includes FCS

0x20

frame has padding between 802.11 header and payload (to 32-bit boundary)

Currently unspecified but used:

Mask

Meaning

0x40

frame failed FCS check

0x80

frame used short guard interval (HT)

Lock quality

Bit Number
7
Structure
u16
Required Alignment
2
Unit
unitless

Quality of Barker code lock. Unitless. Monotonically nondecreasing with "better" lock strength. Called "Signal Quality" in datasheets. (Is there a standard way to measure this?)

Rate

Bit Number
2
Structure
u8
Unit
500 Kbps

TX/RX data rate.

TSFT

Bit Number
0
Structure
u64 mactime
Required Alignment
8
Unit
microseconds

Value in microseconds of the MAC's 64-bit 802.11 Time Synchronization Function timer when the first bit of the MPDU arrived at the MAC. For received frames only.

TX attenuation

Bit Number
8
Structure
u16
Required Alignment
2
Unit
unitless

Transmit power expressed as unitless distance from max power set at factory calibration. 0 is max power. Monotonically nondecreasing with lower power levels.

dB TX attenuation

Bit Number
9
Structure
u16
Required Alignment
2
Unit
dB

Transmit power expressed as decibel distance from max power set at factory calibration. 0 is max power. Monotonically nondecreasing with lower power levels.

dB antenna noise

Bit Number
13
Structure
u8
Unit
dB

RF noise power at the antenna, decibel difference from an arbitrary, fixed reference.

dB antenna signal

Bit Number
12
Structure
u8
Unit
dB

RF signal power at the antenna, decibel difference from an arbitrary, fixed reference.

dBm TX power

Bit Number
10
Structure
s8
Required Alignment
2
Unit
dBm

Transmit power expressed as dBm (decibels from a 1 milliwatt reference). This is the absolute power level measured at the antenna port.

defined-fields/all (last edited 2008-06-19 16:41:44 by JohannesBerg)