OFDMA allows the APs to subdivide the serving channel into sub-channels and to allocate smaller frequencies to each, such that the AP can handle the simultaneous data transmission on the channel to multiple connected devices (OFDMA downlink transmissions), and simultaneous data reception on the channel from multiple connected devices (OFDMA uplink transmissions).
The efficiency of the OFDMA allows the ecosystem to support a much larger capacity of time-sensitive applications that are used by multiple devices simultaneously on the channel, while keeping the traffic performance intact and maintaining the stable performance with negligible jitter, latency, and packet loss for all the connected devices. Without OFDMA, a lower number of connected devices can receive good quality service from the given APs.
