Uncontended Voice and Data Through TDMA Networks

By Rolf Berge
How subsea applications are leveraging satellite technology for the “Internet of Things”
The Internet of Things (IoT) has been a hot topic across many industries in recent years. Whether it’s a fitness tracker, smart refrigerator, thermostat or apps within a car, most people are now connected to electronic devices in ways that they probably wouldn’t have imagined 15 years ago. Experts are predicting that there will be more than 24 billion IoT devices installed and $6 trillion invested in IoT solutions by 2020. At this rate of growth, the IoT ecosystem extends beyond consumer electronics to other industries like healthcare, logistics, agriculture and oil and gas, to name a few. 
For most of these applications, especially those located in remote areas, the IoT has only been made possible through satellite-based communication. For example, companies such as Harris CapRock* work with their customers to provide connectivity through satellite communications, with a specialization in transient environments. One way this is achieved is through Harris CapRock One. It provides a communication service that monitors for and adopts the best-fit satellite, wireless or terrestrial network as a rig or ship moves around the globe. The solution’s multi-band antenna is capable of supporting C-, Ku- and Ka-band and is remotely configurable, saving on the costs associated with an on-site service technician.
With this setup, customers are allowed to freely roam wherever they want worldwide and the equipment self-configures to the most appropriate connection in the given conditions – making IoT applications a reality, even in the middle of the ocean. This type of reliability opens a window to what customers can achieve through communications technology and connectivity, allowing them to derive benefits from the IoT that weren’t previously available. 
Uncontended TDMA Networks 
Another way Harris CapRock achieves connectivity is through uncontended Time Divisional Multiple Access (TDMA) networks. TDMA networks are very flexible in supporting highly mobile assets that need to move from one region of the world to the next. What many customers don’t realize is that service providers have the ability to offer uncontended TDMA networks with a dedicated committed information rate (CIR). This architecture allows access to committed bandwidth levels at all times – an advancement over traditional TDMA networks. Under this network model, an uncontended CIR is like a dedicated lane on the freeway that can only be used by a single company, allowing the company to send any mix of cars, vans and trucks as they like. The dedicated lane is unaffected by rush hour, or activity in other lanes. In other words, and for operators tracking multiple assets or remotely monitoring myriad metrics from a wide array of equipment, the perfect match. TDMA networks are able to react to changing traffic requirements from the VSAT to the hub much faster than a single channel per carrier (SCPC) network. This makes TDMA networks much more appealing when dealing with bursts of traffic or IoT applications. 
In one such application, the results are noteworthy. Harris CapRock deploys voice and data services through an uncontended TDMA network with its customer, Oceaneering, to support live video services which are currently utilized for subsea and topside activities offshore. By nature of the work, Oceaneering’s fleet is almost always located in hard to reach areas making satellite communications a must.
As a global oilfield provider of engineered services and products, primarily to the offshore oil and gas industry, Oceaneering has a focus on deep-water applications. Oceaneering’s business offerings include remotely operated vehicles (ROVs), built-to-order specialty subsea hardware, deep-water intervention and manned diving services, non-destructive testing and inspection, as well as engineering and project management. The company provides the hardware, networking and all communications services to install and backhaul video from even the most remote locations.
For Oceaneering, the IoT is enabled by the use of cameras and sensors on vessels to create feedback to users onboard and onshore. Traditionally, operations personnel were required to monitor gauges and sensors. With the availability of the Harris CapRock satellite communications link, sensors are interconnected and monitored via various gauges and dashboards instead of through manual intervention. 
Through the IoT, companies are given great visibility into their subsea operations. Predictive maintenance has become a more common method to reduce costs, and video is a key tool in validating the wear and use of equipment. Subsea video is used to monitor Oceaneering’s ROV operations and to inspect subsea hardware for any damage or erosion and corrosion issues. Video management is provided through an integrated web-based portal for viewing and management of real-time streaming and historical archiving and review. The user has the ability to tag interest areas for subsequent analysis and view multiple streams in a unified display. The analytics around the video enable clients to measure the amount of surface coasting or rust occurring on assemblies and calculate when to replace them. 

Harris CapRock in Action
Recently, an operation was initiated to verify a leak in one of Oceaneering’s subsea risers which was used to transfer product from the subsea floor to the offshore production platform. With these types of operations, there is quite a bit of ROV work and support around the installation, maintenance and operation of the riser (including frequent inspections) – all requiring subsea video.
To fix the issue, live video was streamed to multiple users in order to design a repair kit for the damaged pipe joint. Measurements were made directly off the video using photogrammetry, which allows precise measurement when two cameras are used in coordination. The cameras on the surface and live streaming were used to conduct operations monitoring and surveillance of activities to provide direct feedback and assistance to crews offshore. Oceaneering was able to successfully conduct a repair of the riser while providing operational visibility to the client – all while the operation was underway through satellite-enabled live streaming video.
Today, several of Oceaneering’s clients now conduct operations through an onshore command center and maintain active communications with the crews offshore operating the equipment. As vessels become more automated, the need for connectivity only increases. The visibility that’s made possible through Harris CapRock’s satellite link has become a necessity for the subsea operations, and through it, Oceaneering has been able to provide more sophisticated solutions because of reliable communications across its fleet of vessels. 
* Editor’s Note: 
On November 1, 2016, Harris’ CapRock Communications commercial business was acquired by satellite communications and network service provider SpeedCast International Limited in a cash transaction valued at $425 million.
(As published in the November/December 2016 edition of Marine Technology Reporter)
Marine Technology Magazine, page 20,  Nov 2016

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