The Council for Scientific and Industrial Research (CSIR) has successfully demonstrated a new broadband underwater data communication system to Armscor. This project aims to provide the South African Navy with fast, reliable acoustic data transfer capabilities for various naval operations.
According to a DefenceWeb article, during testing at the CSIR’s specialised acoustic facility, the system achieved data rates exceeding 240 kbps with near-perfect transmission.
Reliable underwater communication is notoriously challenging because water is a dense medium in which radio waves do not travel well. Unlike terrestrial Wi-Fi or cellular signals that use electromagnetic waves, underwater systems must rely on sound. To overcome the limitations of the aquatic environment, researchers utilised multiple-input multiple-output (MIMO) technology. This approach uses multiple transmitter and receiver transducers to increase bandwidth and improve signal reliability.
The current version of the technology can transmit complex data, such as sonar images, over distances of up to 500 meters. Beyond software improvements, the CSIR developed new mechanical and electronic hardware for two buoy-mounted transmitter and receiver units. These stand-alone systems allow for easier testing and deployment in open water.
This development is a vital step for the future of autonomous underwater vehicles (AUVs). These modern devices are used to map the ocean floor, inspect subsea structures, and ensure the safety of national waterways. During the demonstration, researchers also explored the potential for live video streaming. Fast data transfer allows operators to see what an AUV or a diver sees in real-time; this capability changes how commanders manage underwater search and recovery or mine-clearing missions.
In a related naval project, the CSIR recently integrated its sonar demonstrator into a new towfish. A towfish is a specialised sensor platform that a ship pulls through the water to stabilise sensors and get them closer to the seafloor. This specific platform uses synthetic aperture sonar (SAS) to capture high-resolution acoustic images of the ocean bottom. While the South African Navy already uses multibeam and side-scan sonars for navigation and threat detection, SAS technology offers much higher detail for identifying small objects like mines or wreckage.
Processing the massive amount of data generated by high-resolution sonar is a major technical hurdle. To solve this, the CSIR developed proprietary software that runs on high-performance single-board computers. These units use cutting-edge graphics processing unit (GPU) technology to handle complex calculations. This hardware allows the system to produce final images in near-real-time.
Moving toward real-time image formation is a priority for the Navy. It allows surface vessels and submarines to detect obstacles or potential threats immediately rather than waiting for post-mission data analysis. These advancements ensure that South African naval forces can operate more safely and effectively in increasingly complex maritime environments.
Meanwhile, last August, CSIR built an all-new ground-based detection radar. This new development, known as the Ground-based Surveillance and Classification Radar (GSCR), is intended to integrate with the CSIR’s existing Meerkat wide area surveillance system. The Meerkat platform currently relies on a radar from Reutech Radar Systems, the RSR 904, but the CSIR’s newly developed GSCR offers a more cost-effective alternative.
This innovation reflects the CSIR’s ongoing efforts to enhance surveillance capabilities for a range of applications, from border security to wildlife conservation. The Meerkat system itself is a robust tool, combining radar with day and thermal cameras to enable 24-hour operation. It includes information analysis software capable of detecting, tracking, and classifying individuals entering specific areas. With the ability to monitor up to 200 square kilometres at a time, Meerkat is well-suited for overseeing large expanses, such as borders or nature reserves.
The introduction of the GSCR aims to build on this foundation, bringing additional functionality and efficiency to the platform. One of the standout features of the GSCR is its capacity to classify targets, distinguishing, for instance, between animals and humans. This ability sets it apart from the current setup, where Meerkat’s cameras play a key role in identifying and classifying targets alongside the RSR 904 radar. With the GSCR, there is potential for the radar to operate independently of these cameras, reducing reliance on additional equipment. The CSIR envisions the GSCR enabling unattended automated operation, a feature that could transform how the system is used in the field.