VLF Communications

The ability of VLF and LF radio transmissions to penetrate seawater allows submerged submarines to receive strategic and tactical communications. Drumgrange has been actively involved in the UK VLF Submarine Broadcast Strategic Communications programme since the 1980s having developed bespoke items of equipment that span the entire VLF communications chain from headquarters, transmitter sites, to the submarine platforms. We continue to support, refine and refresh those systems via long term contracts with the UK MoD and other MoD Prime Contractors.

All our current systems have been developed to be compliant with NATO STANAG 5030 Edition 4. Drumgrange is now developing products to be compliant with the new NATO STANAG 4724 which is currently being ratified by NATO member states.

To aid system development, Drumgrange has developed a sophisticated numerical (Matlab/Simulink) modelling environment to support link budget estimation and overall system performance analysis.

We work closely with CESG, the UK Government's National Technical Authority for Information Assurance, during the development and security accreditation of High Grade devices required within these programmes.

In addition to the UK sovereign programmes, Drumgrange also provides VLF/LF Communications equipments to NATO Facilities and for other overseas national programmes.


MSK Demodulators (DDM311)
Designed to meet all the requirements of NATO STANAG 5030, the compact DDM311 enables the continuous off-air data recovery of MSK and FSK from up to five separate VLF radio receivers and 20 data channels simultaneously. In service with NATO, versions are available for onboard naval use to upgrade existing VLF/LF receivers for multichannel MSK service.

VLF/LF Multimode Transmitter Drives (DDR310)
DDR310 enables up to 4 x 50 (or 75) baud keystream data inputs to be formatted and modulated onto a high-stability LF/VLF carrier. The modulated carrier is then passed to the associated transmitter power amplifiers. Versions that incorporate extended or remote control and automatic antenna fine tuning are available. Comprehensive built-in test circuits are included in the design.

Datasheets and Case Studies