Enhancing Time-Domain Interference Alignment for Underwater Acoustic Networks with Cross-Layer Design

Area of Science:

• Computer Science
• Electrical Engineering
• Telecommunications

Background:

• Underwater acoustic (UWA) networks face challenges due to large propagation delays.
• Time-domain interference alignment (TDIA) uses delay-aware scheduling to create idle time for improved MAC layer transmission.
• Perfect interference alignment is difficult in UWA networks with arbitrary delays.

Purpose of the Study:

• To enhance TDIA by integrating power allocation with transmission scheduling across physical and MAC layers.
• To develop a cross-layer design for optimizing UWA network performance.
• To maximize network throughput by jointly optimizing transmission schedule and power.

Main Methods:

• Proposed a quasi-interference alignment (QIA) mechanism for controlled interference on useful signals.
• Formulated an optimization problem to maximize network throughput.
• Divided the optimization into sub-problems for coarse slot scheduling and refined scheduling/power allocation.

Main Results:

• The QIA framework demonstrates superior performance compared to traditional TDIA.
• Simulation results show QIA outperforms genetic algorithm benchmarks.
• The joint optimization of schedule and power allocation effectively improves network throughput.

Conclusions:

• The QIA framework offers a significant advancement in UWA network communication.
• Cross-layer optimization integrating power allocation enhances TDIA's effectiveness.
• QIA provides a robust solution for maximizing throughput in UWA networks with propagation delays.