In Non-Terrestrial Network (NTN) architectures, high bandwidth is critical for transforming satellites from simple “relays” into robust extensions of 5G and 6G ecosystems. It enables the network to handle data-intensive applications in regions where traditional terrestrial infrastructure is absent. High bandwidth allows NTNs to move beyond simple text-based emergency messaging to support broadband-heavy services in remote areas and at distributed gateway sites.

The eT family of high-capacity broadband fiber links connect satellite antennas and ground segments (gateways) to the terrestrial core telecommunications network, facilitating connectivity to standard user devices. A single eT transport link can accommodate any combination of up to ten uplinks and/or downlinks. These links support transport of data, voice, or IoT information from LEO (Low Earth Orbit) satellites to the core network via feeder link infrastructure.

The eT L/S/C-Band SATCOM fiber transport subsystem provides a dense, cost-effective, and reliable RF connection between a satellite antenna and a SATCOM modem in those cases where coaxial cable is impractical or additional security is required. Fiber optic transmitters feature linear uncooled isolated DFB laser diodes. Fiber optic receivers feature high performance InGaAs photodiodes. The standard transported RF frequency band with high spur free dynamic range (SFDR) is 30–3000 MHz. Options exist for extending the frequency range to 6 GHz on the upper end, and/or 10 kHz on the lower end.

The eT fiber subsystem utilizes Coarse Wavelength Division Multiplexing (CWDM) to transport all RF signals between the Indoor Unit (IDU) and the Outdoor Unit (ODU) over a single fiber. Low phase noise reference clocks may be transported from SATCOM modems or timing servers to elements at the antenna in a number of ways. An optional low noise transmitter pre-amplifier ensures a margin on signal-to-noise ratio (especially on low received power downlinks) while keeping the signal in the most linear operating range of the fiber link. Diversity support for multiple fiber routes is optional.

The eT transport subsystem may be monitored in a number of ways. Locally, LEDs and dry contact relay alarms (IDU) provide status. There are multiple ways to monitor the subsystem remotely including SSH command line interface (CLI), HTTP web user interface, and Optical Zonu’s Managed RFoF graphical command and control interface. The management interface also supports SNMP v2 and v3 and the RESTful API.

The standard RF interface is 50Ω SMA (IDU) and 50Ω N (ODU). The ODU is powered from 12 VDC (-48V optional). The IDU may be powered from AC or 48 VDC.