IBSS (ad hoc) with Multiple Traffic Flows

This application is an extension to the Investigating Physical Carrier Sensing in the DCF with Multiple Traffic Flows application note. Instead of a network of 1 AP and 2 STA nodes, this example shows how to run an experiment with 3 IBSS nodes.

The standard AP/STA flavors of 802.11 have a fundamental limitation: The AP is capable of transmitting to any of its association stations, but the STA devices can only directly transmit to the AP. STA devices cannot directly communicate with other STA devices on the BSS without first hopping through the AP.

IBSS devices are different. The "Independent Basic Service Set" allows for any device to communicate to any other device, allowing for more general mesh configurations. Unlike the Investigating Physical Carrier Sensing in the DCF with Multiple Traffic Flows application note, we are not limited to a total of 4 possible flows when using IBSS nodes. In this application note, we extend the network to a total of 6 flows while still only using 3 nodes.

Experiment Details

• Packet Length: 1400 byte payloads (1428 byte MPDUs, with MAC header and FCS)
• PHY Rate: 18 Mbps (QPSK, code rate 3/4)
• Tx Power: -5 dBm
• Trial Duration: 300 seconds
• 2.4GHz channel 6

We use 6 traffic flows in our experiments:

• Flow 1: Backlogged traffic from IBSS_1 to IBSS_2
• Flow 2: Backlogged traffic from IBSS_1 to IBSS_3
• Flow 3: Backlogged traffic from IBSS_2 to IBSS_1
• Flow 4: Backlogged traffic from IBSS_2 to IBSS_3
• Flow 5: Backlogged traffic from IBSS_3 to IBSS_1
• Flow 6: Backlogged traffic from IBSS_3 to IBSS_2