Crest of a Wave

ESSOR Signing Ceremony
Germany is the most recent entrant to the ESSOR programme having formally joined in 2020. Rohde & Schwarz was selected three years earlier in 2017 as the initiative’s German industrial national champion.

This year’s Eurosatory exhibition, held in Paris between 17th and 21st June, was an opportunity to learn about the status and plans for the ESSOR tactical communications waveform initiative.

The European Secure Software Defined Radio (ESSOR) project is multilateral initiative developing several radio-agnostic tactical communications waveforms which can be used by a plethora of transceivers. The project is being realised via an international effort involving Finland, France, Germany, Italy, Poland and Spain. The a4ESSOR consortium is the programme’s industrial element involving Bittium, Indra, Leonardo, Radmor, Rohde and Schwarz, and Thales. ESSOR is managed by OCCAR (Organisation Conjointe de Coopération en Matière d’Armement/Joint Organisation for Armaments Cooperation). OCCAR is a pan-European body tasked with managing European multilateral defence equipment programmes.

One of the key deliverables is the ESSOR High Data Rate Waveform (EHDRWF). The EHDRWF is an Ultra-High Frequency (UHF) waveform using a waveband of 225 megahertz/MHz to 400MHz. Up to 200 nodes can be housed on a single EHDRWF network. The waveform can handle data rates of up to one megabit-per-second. It sustains full duplex data and voice-over-internet-protocol communications. Transmission security includes fast frequency hopping. It can work in environments where Global Navigation Satellite System (GNSS) Position, Navigation and Timing (PNT) signals are badly degraded or denied.

All six countries will be introducing the EHDRWF into their tactical communications over the coming years. Two of the ESSOR nations, Finland and France, have already introduced the waveform into service with their land forces tactical radios. However, the EHDRWF is not the programme’s only deliverable. Narrowband and airborne waveforms are in the offing.


The ESSOR Three-Dimensional Waveform (E3DWF) is optimised for air-ground-air communications, a4ESSOR representatives told Armada. Covering similar UHF wavebands to those used by the EHDRWF the frequency-hopping E3DWF performs simultaneous voice and data transmission. Data rates are dynamic adopting to prevailing electromagnetic conditions. E3DWF uses Multi-hop Ad Noc Networking (MANET) with network synchronisation provided by GNSS PNT signals. The A4ESSOR representatives continued that up to 32 nodes can be accommodated on each E3DWF network.


The ESSOR Narrowband Waveform (ENBWF) complements the wideband EHDRWF for land tactical communications. The a4ESSOR officials said that ENBWF is optimised to support communications in urban, rural, littoral, undulating and mountainous terrain using a MANET architecture. Providing dynamic kilobits-per-second data rates, the ENBWF handles NATO (North Atlantic Treaty Organisation) Restricted voice and data traffic. The waveform can use frequencies of 30MHz to 88MHz, or 225MHz to 400MHz. Like the E3DWF, the ENBWF uses frequency hopping to help resist electronic attack. Network synchronisation is possible with or without a GNSS PNT signal. Up to 60 nodes can be accommodated on each ENBWF network.

Over the longer term, the ESSOR initiative plans to develop a Tactical UHF Satellite Communications Waveform (ESATWF). In the near term, the a4ESSOR officials said that development of the E3DWF could conclude by the end of 2024. Work on the ENBWF is ongoing and could be completed in 2025. Specifications for the EHDRWF have already been enshrined in a draft version NATO’s Standardisation Agreement 5651 (STANAG-5651). ENBWF specifications could be included in the second edition of NATO’s draft STANAG-5630, with E3DWF particulars enshrined in edition four of STANAG-4372.

Enshrining the specifications in the STANAGs would mean that waveforms designed to these stipulations would be compatible with the ESSOR waveforms discussed above. Standardising waveform design will help deepen European and NATO interoperability. Disparate radios used by different NATO forces but with wideband, narrowband and air-ground-air waveforms designed to meet the STANAGs will communicate directly with ease.

The ESSOR programme was launched in 2008 and its efforts are now bearing fruit. Increased adoption of the EHDRWF among and beyond the a4ESSOR nations will be seen in the future. Croatia and the Republic of Ireland are two nations outside the a4ESSOR membership adopting the EHDRWF in their tactical radios. Other militaries will follow suit in the coming years, with the E3DWF and ENBWF set for adoption by the ESSOR member nations and their allies. At a time when Europe faces an ever-growing threat from a resurgent Russia, these efforts to deepen tactical communications interoperability are highly relevant.

by Dr. Thomas Withington