Signal analyzer Wi Fi

Wi-Fi (WLAN) is a wireless communication technology based on the IEEE 802.11 family of standards. It enables devices such as smartphones, laptops, tablets, and IoT devices to connect to local area networks (LANs) and access the internet without physical cables. Wi-Fi operates mainly in the 2.4 GHz, 5 GHz, and 6 GHz frequency bands, depending on the standard, country, and device capabilities.

Typical bandwidths of Wi-Fi channel are 20, 40, 80, or 160 MHz. Some Wi-Fi 7 devices also support 320 MHz channels in the 6 GHz band.

Note: HackRF supports only 20 MHz bandwidth. It can be used for experimental Wi-Fi signal analysis and partial decoding, even when the Wi-Fi channel bandwidth exceeds its maximum instantaneous bandwidth. However, the ability to decode a signal depends on which part of the transmission is captured and which information is required. This may be sufficient to observe certain signal characteristics, but it does not guarantee successful decoding of complete Wi-Fi frames.

Wi-Fi analyzer analyzes legacy 802.11 DSSS and OFDM signals in the selected I/Q channel. It collects access points from Beacon and Probe Response frames and probing clients from Probe Request frames. Only frames with a valid MAC FCS are added to the session tables.

The analyzer keeps the captured Access Points (AP)/client list for the current window session. Client is any device, that can communicate with Access Point. Purple rows identify probing clients.

Channel status

The upper status area shows:

• acquisition state and tuned Wi-Fi channel;
• channel center and I/Q sample rate;
• captured AP and client counts;
• decoded and detected DSSS/OFDM packet counts;
• latest decoded frame, frame classes and frame types;
• elapsed time since the latest channel activity.

The lower status line reports DSSS or OFDM acquisition details. OFDM values include L-LTF correlation, estimated SNR, EVM, carrier-frequency offset and decoded/detected packet counts.

AP and client table

The main table groups access points by BSSID and probing clients by source MAC address. Important columns include:

• SSID / requested SSID - network name advertised by an AP, or names requested by a client. <any network> denotes a wildcard scan.
• BSSID / client MAC - address used to group the row.
• RSSI - received level of the latest decoded frame in dBFS. It is not calibrated dBm.
• Role - Access Point (AP) or Client.
• PHY / Standards - decoded physical layer and generations inferred from advertised capabilities.
• Max advertised PHY - theoretical advertised capability, not measured throughput.
• Channel / width - advertised operating channel and channel-width information.
• Security / WPS - authentication, privacy and Wi-Fi Protected Setup information advertised in management frames.
• Channel util. - QBSS utilization reported by the AP, not an RF-energy estimate made by the analyzer.
• Country / Company / manufacturer / model - advertised metadata and offline MAC-vendor lookup results.
• Beacons, Probe responses, Probe requests - CRC-valid frames observed during this analyzer session.
• Beacons/s / Probe req./min - recent observed rates.
• Estimated BSS start - capture time minus the latest beacon TSF value; during replay it follows the recording timeline.

AP / client details

Select a row and press AP / CLIENT DETAILS for a parameter-by-parameter explanation. AP details include advertised capabilities, security, QBSS load, TSF timing, decoded-frame statistics and RF-quality estimates. Client details include requested SSIDs, randomized/local-address indication, advertised capabilities, WPS identity and recent Probe Request activity.

The COPY DATA button creates a stable TSV snapshot for use in a spreadsheet or diagnostic report.

Interpretation notes

• A locally administered client address is commonly randomized, so its OUI does not reliably identify the device vendor.
• The MAC vendor may identify the radio or module manufacturer rather than the product brand.
• Missing values mean the information was not present in a decoded frame; they should not be interpreted as a negative capability claim.
• Frame and byte counters cover successfully decoded frames only. They are not total channel traffic or throughput measurements.
• Reliable decoding requires the selected channel to fit inside the captured I/Q bandwidth and a signal level that is strong but not clipped.