The need
JET Connectivity is delivering increased 5G connectivity at sea through the deployment of high-bandwidth 5G floating buoys, offering enhanced communication capabilities to the marine sector. These floating 5G base stations aim to support the UK’s priorities of critical national infrastructure for future wireless non-terrestrial network (MNTN). They aim to significantly enhance the security of the maritime sector as well as support the UK Government’s drive towards net-zero ambitions, by servicing offshore wind farms.
To counter the harsh wireless broadcast environment at sea, JET applied coverage enhancement and self-adapting environmental technologies, based on integrated access and backhaul network, to their floating base stations. These were developed using an innovative beam-steering antenna system, with a multi-segment integrated antenna solution, alongside diversity location awareness methods, to achieve a sufficient beamform gain and compensate for the large pathloss on the sea. This plays a crucial role in ensuring the coverage, capacities, and positioning precision of the maritime 5G network.
It was critically important for JET to acquire the necessary support to design, optimise and validate their complex antenna systems. They required expert evaluation of their real-world radio frequency (RF) performance while considering the critical direction-finding algorithms JET develops for GNSS-denied scenarios.
The solution
The National Physical Laboratory (NPL) worked with JET throughout their R&D procedure, helping with the design and characterisation of key devices, optimisation of core algorithms and benchmarking for the entire system.
We worked closely with JET through consecutive Measurement for Recovery (M4R) and Analysis for Innovators (A4I) projects, providing crucial support for the successful release of multiple innovative products. This included JET’s mechanically selectable directional antenna, linear polarised beam switching directional antenna array, and high gain performance multi-band omni antenna system.
Throughout these projects, NPL provided:
- consultation on the initial prototype design of the multi-beam antenna array
- improvements to key design parameters based on full-wave numerical software simulations
- radiation characterisation of antenna systems from multiple domains, such as frequency and spatial domain performance
- verification of the hardware implementation within the design
- evaluation of coupling interference between adjacent antennas operating at different frequency ranges
- impact assessment of antenna housing.
Alongside measurement of the antenna system, NPL developed an innovative over-the-air Radio Frequency testbed. We also developed methods for assessing the performance of JET’s wireless system and the accuracy of its innovative direction-finding algorithm. The testbed, based on software-defined radio (SDR), operates over a wide band. The maximum 1 GHz instantaneous bandwidth ensures high-resolution measurement accuracy in the delay domain and the full support The 3rd Generation Partnership Project (3GPP) 5G new radio (NR) protocol.
By exploring the flexibility of a SDR platform, NPL was able to develop a sophisticated tool which includes the 5G NR signal generator and receiver, customisable interference signal generator and the anechoic chamber controlling software to form a versatile testbed.
Bespoke measurement campaigns were created to comprehensively evaluate the link performance and direction-finding accuracy of JET’s entire wireless system under flexibly configurable incidence signals, with adjustable parameters such as frequency band and receiving power level, (Tx) waveform, and interference signal generation.
The JET-6 Merida platform, where the antenna has been installed dockside in Dundee.
The impact
Due to NPL’s involvement in the project, the function and performance of JET’s product have been significantly improved. The coverage of their 5G network at sea improved by nearly seven-fold compared with the previous system. This will pave the way for the creation of a connected, safer, more secure, and environmentally sustainable global Blue Economy. The newly applied operation frequency bands successfully reduce the overall dimension and weight of the communication subsystem. The validation of the direction-finding algorithm has enabled JET to further develop and apply the entire 5G network-based positioning service on the buoy as the wireless beacons.
Because of its flexibility and adaptability, the innovative testbed and associated measurement method can be further tailored to fit a wide range of future applications.