NL Series LF PNT Transmitters

NL Series

Data Capable LF PNT Transmitters

Nautel’s NL Series sets a new standard of low frequency, data capable PNT transmitters with outstanding performance, rugged design and operational ease in the industry’s most compact enclosure.

The NL Series is the smallest yet most advanced, fully solid-state eLORAN (Enhanced Long Range Navigation) transmitter available.


The NL Series features exceptional pulse stability, 70% efficiency*, and unmatched levels of redundancy with the capability to fully monitor critical system and LRU parameters, status and alarms via dual Ethernet ports.

The dual Ethernet ports also allow fault diagnosis to be performed to LRU level while the system remains fully operational.

Highlights include:

  • Scalability from tens of watts to more than 1 MW.
  • Patent pending pulse power recovery technique results in outstanding efficiency.
  • Precise, software definable pulse and modulation control.
  • Lightweight, hot-swappable, redundant power amplifiers.
  • Class leading space efficiency.
Models Scalability from tens of watts to more than 1 MW

The NL Series platform is extremely scalable utilizing Nautel combining techniques that have been proven reliable
in the field for over 25 years at peak power levels of more than 1.5 MW.

The unique low-power scalability of the NL Series opens up a whole new set of cost effective coverage gap applications. The NL Series also supports increased average power capability allowing higher pulse rates and future or alternate modulation techniques.

Patent Pending Pulse Power Recovery Technique for Outstanding Efficiency

The building block of the NL Series is a Class D RF amplifier with Nautel’s patent pending pulse power recovery technique which utilizes power that, using current technology, is normally dissipated in the antenna. The result is an RF module with outstanding efficiency regardless of antenna height.

Overall efficiency of the NL Series transmitter typically reaches 70%* or better. High efficiency means less energy is wasted as heat which reduces cooling and ventilation costs.

Precise, Software Definable Pulse and Modulation Control

Advanced Digital Signal Processing (DSP) techniques are utilized to generate a very precise, software definable pulse and modulation control. Pulse Optimization is included for antenna system resistance changes.

The ability to configure the pulse shape via software allows for current and future modulation techniques to be easily implemented, “future-proofing” the NL Series.

Lightweight, Hot-Swappable, Redundant Power Amplifiers

Redundant, hot-swappable PAs with front panel access switch on and off in sequence to generate the software defined signal envelope. An additional number of redundant PAs, which are in the “off” mode, are supplied as active spares further increasing the robustness of the system.

The NL series can experience significant RF power amplifier failure with no change in pulse shape, timing or data. Further losses reduce amplitude while maintaining the integrity of pulse shape and timing.

PA replacement if necessary can be accommodated without the need of any special tools, lifting assemblies and without need to interrupt the signal transmission.

Class Leading Space Efficiency

NL Series transmitters are typically one third the size of current solid state high power LF PPM transmitters. The compact footprint continues to offer safe, easy and spacious access to all major, serviceable assemblies and modules.

The high energy efficiency offered by NL Series also translates into additional space efficiency since less space needs to be allotted to HVAC services and back-up power sources.

Address GNSS Vulnerabilities and Gain Sovereign Control

When deployed in a cost effective terrestrial network, Nautel’s eLORAN transmitters give authorities sovereign control over navigation and timing. Low frequency terrestrial signals offer increased interference tolerance. The co-primary approach draws on the strengths of both the terrestrial and satellite networks where either system can be primary. That means sovereign choice, sovereign control and decreased vulnerability.

Together with our global partner, UrsaNav Inc., Nautel provides turnkey eLORAN solutions, including system design, timing and control equipment, advanced receivers, data channel techniques, and differential LORAN reference equipment. Read this joint UrsaNav/Nautel white paper Leadership in Resilient PNT.