Power Allocation Scheme for Non-Orthogonal Multiple Access in Underwater Acoustic Communications

Area of Science:

• Wireless Communication
• Network Engineering
• Oceanography

Background:

• Non-orthogonal multiple access (NOMA) is crucial for enhancing spectral efficiency in wireless networks.
• Underwater acoustic sensor networks (UWASNs) face unique challenges, including limited bandwidth and high latency.
• Existing power allocation schemes like sum-rate maximization (SRM) are suboptimal in UWASNs due to unequal transmission times.

Discussion:

• The proposed Equal Transmission Times (ETT) power allocation scheme addresses resource wastage in UWASNs.
• ETT ensures equal transmission times across different paths by considering buffer status.
• This approach mitigates performance degradation inherent in terrestrial-based schemes when applied to underwater environments.

Key Insights:

• ETT significantly improves the overall sum-rate in UWASNs compared to SRM.
• The scheme effectively prevents resource wastage caused by disparate transmission durations.
• ETT achieves performance comparable to SRM in terms of maximum sum-rate.

Outlook:

• Further research can explore adaptive ETT schemes for dynamic UWASN conditions.
• Investigating the impact of ETT on energy efficiency and network lifetime is warranted.
• The ETT scheme holds potential for optimizing data transmission in other delay-sensitive underwater networks.