34.4. API and behavior changes across releases

This page tracks the most relevant changes to the API and behavior of the wifi module occurred across the various releases of ns-3.

34.4.1. ChannelSettings attribute

Prior to ns-3.36, channels, channel widths, and operating bands were set separately. As of ns-3.36, a new tuple object that we call ChannelSettings has consolidated all of these settings. Users should specify the channel number, channel width, frequency band, and primary channel index as a tuple (and continue to set the Wi-Fi standard separately). Since ns-3.43, this attribute can contain multiple tuples to support 80+80MHz operating channels.

For instance, where pre-ns-3.36 code may have said:

WifiPhyHelper phy;
phy.Set("ChannelNumber", UintegerValue(36));

the equivalent new code is:

WifiPhyHelper phy;
phy.Set("ChannelSettings", StringValue("{36, 20, BAND_5GHZ, 0}"));

which denotes that channel 36 is used on a 20 MHz channel in the 5GHz band, and because a larger channel width greater than 20 MHz is not being used, there is no need to indicate the primary 20 MHz channel so it is set to zero in the last argument. Users can read Channel, frequency, channel width, and band configuration for more details.