This example shows how to use the Universal Software Radio Peripheral (USRP®) device using SDRu (Software Defined Radio USRP®) System objects™ to implement a WLAN receiver. The receiver is able to recover 802.11™ OFDM non-HT beacon frames transmitted over the air from commercial 802.11 hardware.
WLAN System Toolbox™ provides functions and tools to decode 802.11 waveforms. This example shows how to receive signals from commercial WLAN transmitters in MATLAB using USRP®. A receiver design is demonstrated including synchronization, transmission configuration recovery, and payload decoding for non-HT packets.
In this example, OFDM beacon packets corrupted by the transmission over the air are captured and processed to recover the payload contents. To recover beacon packets the receiver performs packet detection, symbol timing and frequency offset correction, and L-SIG and payload decoding. The resulting payload bits are then evaluated to determine whether the payload is a beacon frame and the contents are displayed as appropriate.
To view an example of a WLAN front end processing which does not require SDR hardware see 802.11 OFDM Beacon Receiver with Live Data.
This example requires the USRP®-based radio support package. This can be installed using the Add-On Explorer.
More information about other supported SDR platforms can be found here.
The full example description and source code can be found in the list of examples using USRP® under the name "IEEE 802.11 WLAN - OFDM Beacon Receiver with USRP® Hardware".
Universal Software Radio Peripheral® and USRP® are trademarks of National Instruments Corp.