Executive Summary
This thesis proposes a scheme for short-range (<500m) underwater acoustic communications in shallow water, adapting an existing commercial modem. It utilizes a higher carrier frequency (45 kHz) and increased spectral bandwidth to achieve greater channel capacity. The scheme, combining MFSK and OFDM, is analyzed for its resilience against multipath interference and intersymbol interference (ISI).
Why It Matters
This document is crucial for defense analysts focusing on naval capabilities, as it details advancements in underwater acoustic communication, a critical component for submarine operations, unmanned underwater vehicles (UUVs), and maritime intelligence gathering.
Key Takeaways
- A new scheme for short-range (<500m) underwater acoustic communication is proposed, leveraging higher frequencies (45 kHz) for increased channel capacity.
- The scheme combines M-ary Frequency-Shift Keying (MFSK) and Orthogonal Frequency-Division Multiplexing (OFDM) to create a multi-channel MFSK modulation.
- Multipath interference and intersymbol interference (ISI) in shallow water environments are key challenges addressed, with multiplexing proposed for better protection against ISI.
Strategic Relevance
Advancements in underwater acoustic modems directly enhance naval communication capabilities, enabling more robust and higher-bandwidth data transfer for submarines, UUVs, and sensor networks. This is critical for intelligence, surveillance, reconnaissance (ISR), command and control (C2), and tactical operations in contested maritime environments.