- \n
- The need to wait for the vehicle to surface to retrieve and process image data into useful maps and high-quality visuals.<\/li>\n<\/ul>\n\n\n\n
The CSIR team is solving the first problem in imaging using specialised signal and image processing algorithms.<\/p>\n\n\n\n
They also employ novel transducers, electrical components that act as underwater antennas to transmit and receive sound waves.<\/p>\n\n\n\n
Compared to traditional transducers, these locally developed, wide-bandwidth components give the CSIR’s SAS systems four times more bandwidth.<\/p>\n\n\n\n
More bandwidth means higher data rates with fewer errors, which translates into higher-resolution images.<\/p>\n\n\n\n
“SAS is like the high definition television version of sonar,” said Josiah Jideani, a senior engineer in the CSIR’s ultrasonics research group.<\/p>\n\n\n\n
“SAS shines when you’re looking for very small targets or objects that conventional types of sonar won’t be able to detect.”<\/p>\n\n\n\n
In the oil and gas industry, SAS can be used for underwater pipeline inspections to check for small leaks or damage.<\/p>\n\n\n\n
It can also be used for mineral prospecting, geological surveys, marine archaeology, buried underwater mine detection and undersea internet cable monitoring.<\/p>\n\n\n\n
Using drones and towed underwater platforms<\/h2>\n\n\n\n
![\"\"](\"https:\/\/mybroadband.co.za\/news\/wp-content\/uploads\/2026\/04\/2-8-1200x382.jpg\")
<\/figure>\n\n\n\nThe sonar system can be mounted on Autonomous Underwater Vehicles (AUVs) or on a towed underwater platform.<\/p>\n\n\n\n
The challenge is maintaining a stable speed and straight trajectory, both of which are essential for synthetic aperture processing.<\/p>\n\n\n\n
Light boats and surface waves introduce motion that must be corrected algorithmically, in addition to imaging and autofocusing algorithms.<\/p>\n\n\n\n
At the CSIR underwater testing facility in Pretoria, the sonar team calibrates the underwater transducers and electronics.<\/p>\n\n\n\n
They also fine\u2011tune signal processing algorithms and evaluate performance under controlled conditions.<\/p>\n\n\n\n
The team then performs ocean and dam tests that introduce uncontrollable variables such as waves, currents, speed changes and platform instability.<\/p>\n\n\n\n
Data collected during field tests are returned to the facility, where the team adjusts the algorithms to account for real\u2011world conditions.<\/p>\n\n\n\n
This iterative cycle between controlled testing and field deployment is central to the technology development process.<\/p>\n\n\n\n
In parallel, researchers are tackling the second problem: how to retrieve information from the surface while a system remains submerged.<\/p>\n\n\n\n
CSIR senior engineer Elna Niemann explained that radio waves used for high-speed communication above water typically don’t travel well underwater.<\/p>\n\n\n\n
“You can’t just submerge a wireless modem underwater and get the same kind of performance you would on land,” she said.<\/p>\n\n\n\n
However, sound waves travel very well underwater. Her team is developing an underwater wireless acoustic communication system.<\/p>\n\n\n\n
Also known as Broadband Underwater Data Communication, this is, in essence, underwater Wi-Fi using sound.<\/p>\n\n\n\n
The novelty lies in a specialised ultra-wide bandwidth transducer that provides up to five times more bandwidth than commercial acoustic modems.<\/p>\n\n\n\n
“We can offer internet-like speeds compared to the commercial offering, which is more in line with telegraph speeds,” she said.<\/p>\n","protected":false},"excerpt":{"rendered":"
South African researchers have developed underwater Wi-Fi technology to transmit sonar images almost instantly.<\/p>\n","protected":false},"author":23,"featured_media":641401,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[13],"tags":[104579,20101,3446,104580,104578,104577,104576,104575],"class_list":["post-641394","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wireless","tag-autonomous-underwater-vehicles-auvs","tag-council-for-scientific-and-industrial-research-csir","tag-csir","tag-elna-niemann","tag-josiah-jideani","tag-kiri-nicolaides","tag-synthetic-aperture-sonar-sas","tag-underwater-wi-fi"],"_links":{"self":[{"href":"https:\/\/mybroadband.co.za\/news\/wp-json\/wp\/v2\/posts\/641394"}],"collection":[{"href":"https:\/\/mybroadband.co.za\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mybroadband.co.za\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mybroadband.co.za\/news\/wp-json\/wp\/v2\/users\/23"}],"replies":[{"embeddable":true,"href":"https:\/\/mybroadband.co.za\/news\/wp-json\/wp\/v2\/comments?post=641394"}],"version-history":[{"count":3,"href":"https:\/\/mybroadband.co.za\/news\/wp-json\/wp\/v2\/posts\/641394\/revisions"}],"predecessor-version":[{"id":641464,"href":"https:\/\/mybroadband.co.za\/news\/wp-json\/wp\/v2\/posts\/641394\/revisions\/641464"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/mybroadband.co.za\/news\/wp-json\/wp\/v2\/media\/641401"}],"wp:attachment":[{"href":"https:\/\/mybroadband.co.za\/news\/wp-json\/wp\/v2\/media?parent=641394"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mybroadband.co.za\/news\/wp-json\/wp\/v2\/categories?post=641394"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mybroadband.co.za\/news\/wp-json\/wp\/v2\/tags?post=641394"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}