Development of a 1 Mbps low power acoustic modem for underwater communications

Abstract

Underwater wireless communication systems are becoming a priority in terms of research and technological development due to the increasing demand for exploring the oceans in areas such as pharmaceutical, oil, minerals, environmental and biodiversity. This demand is increasing exponentially with the need for high data rate and near-real-time communications. In this work an underwater low power acoustic modem to operate over tens of meters, achieving a maximum data rate of 1 Mbps, is presented. This solution allows for reprogramming the digital signal processing block enabling the use of different types of digital modulations in order to improve the modem's performance. The system is based on a poly(vinylidene fluoride) PVDF ultrasonic emitter transducer which is capable of sending high quality signals needed for digital modulations with high symbol rates per carrier period. BPSK, BFSK and OOK modulations have been tested. The results registered were 3x10 -3 BER with 1 Mbps OOK, 2.3x10-5 with 512 kbps and 1x10-8 with 256 kbps.

Wideband and Wide Beam Polyvinylidene Difluoride (PVDF) Acoustic Transducer for Broadband Underwater Communications

“…Despite the recent developments presented in the literature about acoustic transducers, there is no reliable solution that meets all the needs in underwater broadband wireless communications for a distance coverage range up to 15 m [10]. In this sense, and in order to fill this technological gap, the present work describes the development and implementation of a wideband wide beam PVDF acoustic transducer to operate as emitter for frequencies up to 1 MHz.…”

Exploration of underwater life with an acoustically controlled soft robotic fish

“…Although Woods Hole Oceanographic Institution modems (58,59) can overcome challenges such as multipath effects and Doppler shifts (60), their size and power consumption are too large for fish-sized robots. Similarly, other modems (61,62) focus on higher data rates and longer ranges than required for remote-controlled operation by a diver, rendering them too bulky, expensive, and energy-consuming for our present application. Some acoustic modems (52) use hardware-defined signal generation and detection, but this limits available processing and reduces versatility.…”

A Compact Acoustic Communication Module for Remote Control Underwater

“…A modem developed at the Woods Hole Oceanographic Institution [14,12] is able to operate in this di cult environment, but the physical size and the power consumption are too large for the compact underwater devices targeted in this paper. Similarly, many other modems such as those described in [17,19] and commercially available modems such as [4,15] are generally focused on higher data rates and longer ranges than are required for remote underwater operation by a diver, and become too bulky and expensive for the presented application. Additionally, many acoustic modems such as [22] use hardware-defined signal generation and detection, which limits the available processing and reduces versatility.…”