Toggle Main Menu Toggle Search

Open Access padlockePrints

Low-Power Environmentally Friendly Underwater Acoustic Communication Using Pseudo-Noise Spreading Sequences

Lookup NU author(s): Kalin Dimitrov, Jeffrey Neasham, Professor Bayan Sharif, Dr Charalampos Tsimenidis, Dr Gerry Goodfellow

Downloads

Full text for this publication is not currently held within this repository. Alternative links are provided below where available.


Abstract

This paper explores possible approaches to very low power, environmentally friendly underwater acoustic communications with signals that are well disguised in the background noise. While the underwater acoustic spectrum is currently not regulated, it is likely that it will be in the future, both to ensure human activities have minimal impact on marine wildlife and to minimise interference with other acoustic systems. Two variations on a low bit rate spread spectrum modulation scheme using multiple pseudo-noise codes are compared, the first using conventional BPSK modulation and the second using "carrierless" modulation (bandlimited noise). Simulation shows that for a given time-bandwidth product and data rate, the carrierless modulation outperforms the BPSK system. Additional benefits from the carrierless approach are a simpler transmitter and receiver structure, reduced cost of implementation and better noise-like statistics for blending into background noise. The carrierless system is tested in recent trials in the North Sea and was effective for communication at ranges up to 4km with only 0.1W of acoustic power transmitted (160 dB re 1 mu Pa at 1m). The maximum bit rate tested for systems using length 4095 PN codes was 70bps, while for a system with length 8191 codes 35bps, with the latter system being capable of 48bps if it's full codebase capacity is used. The authors conclude that this is a potentially powerful technique that, combined with advanced error correction codes and Doppler compensation methods, could form the basis of very robust, long range, environmentally friendly acoustic modems for a variety of command/control and low volume sensor data gathering applications.


Publication metadata

Author(s): Dimitrov KE, Neasham JA, Sharif BS, Tsimenidis CC, Goodfellow GM

Publication type: Conference Proceedings (inc. Abstract)

Publication status: Published

Conference Name: Oceans

Year of Conference: 2012

Pages: 1-5

ISSN: 0197-7385

Publisher: IEEE

URL: http://dx.doi.org/10.1109/OCEANS-Yeosu.2012.6263622

DOI: 10.1109/OCEANS-Yeosu.2012.6263622

Library holdings: Search Newcastle University Library for this item

ISBN: 9781457720918


Actions

Find at Newcastle University icon    Link to this publication


Share