Measurement Pilot

Measurement Pilot
The Measurement Pilot frame provides a subset of the information provided in a Beacon frame, is smaller
than a Beacon, and is transmitted more often than a Beacon. The purpose of the Measurement Pilot frame is
to assist a STA with scanning.
Frame
The frame request/report pair returns a picture of all the channel traffic and a count of all the frames received
at the measuring STA. For each unique Transmitter Address, the STA reports the Transmitter Address,

number of frames received from this transmitter, average power level (RCPI) for these frames, and BSSID
of the transmitter.
Channel load
The channel load request/report pair returns the channel utilization measurement as observed by the
measuring STA.
Noise histogram
The noise histogram request/report pair returns a power histogram measurement of non-IEEE 802.11 noise
power by sampling the channel when virtual carrier sense indicates idle and the STA is neither transmitting
nor receiving a frame.
STA statistics
The STA statistics request/report pair returns groups of values for STA counters and for BSS Average
Access Delay. The STA counter group values include transmitted fragment counts, group addressed
transmitted frame counts, failed counts, retry counts, multiple retry counts, frame duplicate counts, Request
to Send (RTS) success counts, RTS failure counts, Acknowledgement (ACK) failure counts, received
fragment counts, group addressed received frame counts, FCS error counts, and transmitted frame counts.
BSS Average Access Delay group values include AP average access delay, average access delay for each
access category, associated STA count, and channel utilization.
Location
The Location request/report pair returns a requested location in terms of latitude, longitude, and altitude. It
includes types of altitude such as floors and permits various reporting resolutions. The requested location
may be the location of the requestor (e.g., Where am I?) or the location of the reporting STA (e.g., Where are
you?)
Measurement pause
The measurement pause request is defined, but no report comes back from this request. The measurement
pause permits the inclusion of a quantified delay between the execution of individual measurements that are
provided in a series within a measurement request frame. The measurement pause used as the last
measurement in a frame provides control of the measurement period when measurement request frames are
to be repeated.
Neighbor report
The neighbor report request is sent to an AP, which returns a neighbor report containing information about
known neighbor APs that are candidates for a service set transition. Neighbor reports contain information
from the table dot11RMNeighborReportTable in the MIB concerning neighbor APs. This request/report pair
enables a STA to gain information about the neighbors of the associated AP to be used as potential roaming
candidates.
 Link measurement
The link measurement request/report exchange provides measurements of the RF characteristics of a STAto-
STA link. This measurement indicates the instantaneous quality of a link.