Communication Revolution in Blue Oil Fields: ZTE Helps CNOOC Set a New Benchmark in Smart Energy

In July 2023, with the official launch of the 5G private network on the Bohai Bay drilling platform, China National Offshore Oil Corporation (CNOOC) ushered in the 5G era for its offshore oil fields. The integrated private network solution—combining submarine optical cables, microwave links, and 5G technology—was jointly developed by ZTE, Liaoning Telecom, and CNOOC to address communication challenges in sea areas 40 to 300 kilometers offshore. This breakthrough in deep-sea communication technology marks a historic shift from labor-intensive to data-driven operations in China's largest offshore oil field.

Pilot Breakthrough in Bohai Bay

Traditional offshore oil fields relied on microwave equipment installed on main platforms for communication with land, while nearby vessels had to switch to satellite communications once they sailed away. These legacy networks were characterized by high latency, low speed, and limited mobility, and were prone to frequent interruptions during severe weather conditions like typhoons and heavy fog, which severely constrained safe and efficient maritime operations. As a result, CNOOC urgently needed a communication revolution to address these long-standing bottlenecks affecting offshore operations.

As part of this communications revolution, ZTE collaborated with Liaoning Telecom to pilot the deployment of a 5GC control plane, installing one UPF along with 5G base stations on each drilling platform. By connecting CNOOC and seven drilling platforms in Bohai Bay via submarine optical cables and utilizing the ultra-long-distance coverage of base stations, 5G communication was established across the surrounding sea areas.

With a unified 5GC control plane for all drilling platforms, seamless handovers and interoperability among surrounding operational vessels have been achieved. Data from operational vessels and platform equipment is transmitted back via 5G private network base stations to the on-platform UPF, where local data offloading is performed before being forwarded to application servers both on the platforms and at headquarters for further analysis. This ensures that data remains within operational areas while meeting requirements for high bandwidth and low latency.

Scaling Success Across Maritime Areas

Building on the initial success, other branches CNOOC sought to replicate the benefits of this digital transformation. In 2024, following the deployment in Bohai Bay, drilling platforms across the East China Sea, South China Sea, and Beibu Gulf began deploying UPFs and 5G base stations, all connected to the 5GC control plane at headquarters. Thus, a preliminary cross-sea 5G private network took shape, seamlessly integrating the blue territory into the digital pulse of the nation.

In this network, ZTE tailored its solutions to the specific conditions of different maritime areas.

Wireless  

At the wireless level, to meet the coverage requirements of CNOOC's offshore platforms and surrounding maritime areas, ultra-long-range base stations were deployed on offshore platforms. These base stations utilize beamforming technology, which adjusts the phase of signals emitted from each antenna to create an electromagnetic wave superposition at the terminal reception point, thereby enhancing signal strength. Offshore terminal  access the 5G network via high-gain SE9102 gateways. Based on antenna characteristics, directional antennas are installed on oil extraction vessel platforms, while omnidirectional antennas are utilized on shift vessels. By modifying terminals to support external antennas, RF gain is improved, wireless links are optimized, and data transmission rates are maximized.

Transmission

At the transmission level, satellite backhaul is adopted for the Shanghai offshore platform due to its considerable distance from the mainland. Meanwhile, drilling platforms in Liaoning, Dongying, Shenzhen, and Zhanjiang are connected via submarine optical cables to Telecom A and B equipment. The equipment of various branches of CNOOC connect to the headquarters' 5GC through inter-provincial OTN dedicated lines, establishing internal CNOOC networks that transmit the control signaling of the 5G private network. This approach replaces the previous microwave solution, ensuring stable and reliable transmission.

Core Network

At the core network level, ZTE adopts a lightweight i5GC for ToB scenarios, encompassing key 5GC network elements such as AMF, SMF, UDM. The goal is to provide industry customers with a lightweight, industry-customized, and easy-to-maintain 5G core network.

• Lightweight deployment: i5GC occupies less space, consumes less energy, requires less hardware investment, and can be deployed on-demand in a variety of environments, including enterprises, parks, airports, and mines.
• Extensive connectivity: i5GC can be extended to support integrated access for 4G, 5G, eMTC, and NB-IoT, as well as future evolution to fixed-mobile convergence (FMC). It can also enable innovative features such as 5G LAN, QoS monitoring, FRER, and TSN.
• Strong security: Leveraging 5G’s built-in confidentiality and integrity protection features, i5GC prevents terminal data leakage and ensures secure terminal access. To meet the varying security needs of different business traffic within industry clients, services can be isolated using different domain names (DN) and separate secure tunnels, ensuring that offshore operations and office traffic remain fully isolated and interference-free.

Furthermore, the integrated hardware-software design of i5GC reduces the complexity of deployment, operation, and usage, while offering simple system monitoring functions for enterprise-level autonomous maintenance. Customized service solutions, distinct from general-purpose core networks, are designed to address the diverse application scenarios of industry users.

Deployment, Operations and Delivery

At the overall architecture level (see Fig. 1), Tianjin hosts the deployment of the 5GC control plane and unified network management system, while UPFs are deployed on offshore drilling platforms across the Bohai Bay, East China Sea, South China Sea, and Beibu Gulf regions. Wireless base stations and UPFs in regions like Liaoning, Dongying, Shenzhen, and Zhanjiang are connected to land-based office networks via submarine optical cables, while the Shanghai platform is connected via satellite. All terminals are managed under unified numbering by the UDM within the headquarters' i5GC, supporting roaming scenarios for operational vessels of different branches across various maritime areas. Each branch uses distinct number segments to facilitate easier management.

Additionally, the R88 unified network management is deployed at the headquarters, enabling comprehensive O&M across wireless, transmission, and core networks. It provides robust capabilities including network configuration, fault monitoring, statistical analysis, performance tracking, version upgrades, and security management. The embedded iDOS enterprise portal offers both business and device dashboards, supporting visual operations through large-screen displays.

To accelerate the rapid deployment and commissioning of CNOOC’s network, ZTE offers a “three-no” solution—no design, no on-site installation, and no debugging—with all pre-installation completed at the production line. Upon arrival at branch locations, one-click reconfiguration is performed based on the site environment. Once transported to drilling platforms, the equipment can be directly connected and powered on for immediate operation, enabling site activation in less than 24 hours and significantly shortening project timelines.

The collaboration between ZTE and CNOOC demonstrates that a 5G private network not only resolves communication bottlenecks in offshore oil fields, but also redefines the production paradigm of marine oil and gas development. It delivers replicable results and provides useful references for more remote marine scenarios in the future. As CNOOC's chief engineer remarked, "5G is not merely a technological upgrade—it is the golden key to unlocking the treasure trove of deep-sea energy."