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IEEE 802.11ax OFDMA Resource Allocation with Frequency-Selective Fading.
Sergei Tutelian1, Dmitry Bankov1, Dmitri Shmelkin2
1Institute for Information Transmission Problems, Russian Academy of Sciences, 127051 Moscow, Russia.
Sensors (Basel, Switzerland)
|September 28, 2021
Summary
This study introduces an Orthogonal Frequency Division Multiple Access (OFDMA) resource allocation algorithm for IEEE 802.11ax Wi-Fi. The new approach enhances efficiency and performance, even with imperfect channel information.
Area of Science:
- Wireless communication networks
- IEEE 802.11ax standards
- Orthogonal Frequency Division Multiple Access (OFDMA)
Background:
- Efficient resource allocation is crucial for multi-user transmissions in Wi-Fi using OFDMA.
- Algorithms must adapt to dynamic channel conditions like frequency-selective fading.
Purpose of the Study:
- To develop an OFDMA resource allocation algorithm for IEEE 802.11ax uplink transmissions.
- To propose power and modulation/coding adaptation for varying channel conditions, even with outdated access point information.
Main Methods:
- Developed a novel OFDMA resource allocation algorithm tailored for frequency-selective fading.
- Proposed an adaptive approach for user transmission power and modulation and coding schemes (MCS).
Main Results:
- The proposed algorithm doubles goodput in Wi-Fi networks.
- Data transmission time is halved, even in dense access point deployments.
- The approach remains efficient with outdated channel state information.
Conclusions:
- The presented OFDMA scheduling and power allocation strategy significantly improves Wi-Fi performance.
- This method offers a robust solution for high-density wireless environments facing channel variability.
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