Energy-efficient UAV communication: A NOMA scheme with resource allocation and trajectory optimization.

Area of Science:

• Wireless Communication
• Optimization Theory
• Aerial Networks

Background:

• Unmanned Aerial Vehicles (UAVs) offer flexible deployment as aerial base stations (ABS).
• Nonorthogonal Multiple Access (NOMA) enhances spectral efficiency compared to Orthogonal Multiple Access (OMA).
• Energy efficiency (EE) is a critical design parameter for sustainable wireless networks.

Purpose of the Study:

• To develop an energy-efficient downlink NOMA scheme using a UAV-aided wireless communication system.
• To maximize the overall energy efficiency by jointly optimizing resource allocation and UAV trajectory.
• To address the challenges posed by UAV mobility and communication constraints.

Main Methods:

• A UAV energy efficiency (EE) model was developed considering UAV velocity and maneuverability constraints.
• An EE maximization problem was formulated, jointly optimizing ground user transmit power and UAV trajectory.
• The nonconvex optimization problem was converted to a convex form using three user clustering algorithms.
• An iterative alternating optimization approach was employed for rapid convergence.

Main Results:

• The proposed UAV-NOMA scheme demonstrated significant improvements in energy efficiency.
• The developed algorithm achieved nearly 99.6% superiority over conventional OMA schemes.
• The joint optimization of resource allocation and UAV trajectory effectively enhanced system EE.

Conclusions:

• The UAV-aided NOMA scheme is a promising approach for improving energy efficiency in wireless networks.
• The proposed optimization framework effectively balances resource allocation and trajectory planning for enhanced EE.
• This research provides a valuable contribution to the field of energy-efficient aerial wireless communication.