John Dix, Sales Manager for Land Communications at Thales, talks about how the invasion of Ukraine has highlighted a stark reality: failure to control radio frequency (RF) emissions can mean near-immediate destruction from enemy artillery or drone strikes.  This has made low probability of detection (LPD) communications not just an advantage, but a necessity for military survivability. 

The new battlefield reality

For centuries, military strategy focused on firepower and manoeuvrability, but recent conflicts show stealth is as vital as strength. The modern frontline is a digital hunting ground, where electronic warfare (EW) systems can detect, locate, and target forces in a matter of minutes.

The EW detection threat

EW has evolved to the point where even brief radio transmissions can be intercepted and geolocated with deadly precision. Traditional combat radios, particularly those using high-power, high frequency, very high frequency and ultra high frequency transmissions, are especially vulnerable.

In the invasion of Ukraine, early in the conflict, soldiers using these radios were said to be targeted by artillery strikes within just a quarter of an hour of making a transmission. As EW systems have been refined, however, the time from detection to strikes have been reduced yet further, to a few minutes. 

With every technological leap in EW, military forces must rethink how they communicate. The era of casually using a radio and expecting operational security is very much at an end.

What enables LPD?

To stay ahead of these threats, militaries must prioritise LPD principles in their communications. The goal is to minimise detectability while maintaining effective coordination. This involves several techniques:

1. Adaptive power management

One of the simplest, yet most effective ways to reduce detectability, is to transmit at the lowest necessary power level. On the frontline, it is all too easy to be tempted to crank your radio up to maximum power to ensure you remain connected.  It is one less thing to think about, and I know this is what I, and fellow soldiers, would often do. However, this practice significantly increases the risk of detection.

Instead, adopting the practice of adaptive power control, ensuring that transmissions are made at the minimum wattage required for successful communication, dramatically reduces the likelihood of detection.

2. Minimising time on air

Every second spent transmitting increases the likelihood of detection. In my experience, soldiers can tend to adopt lengthy voice transmissions for routine communication, yet on today’s frontline, this would create an extended RF footprint that enemy EW could easily exploit.

To combat this, soldiers are being asked to consider best practice methods of limiting time on air – i.e. rather than sending this in a voice transmission, can the data be sent as a short-burst packet (containing typed-up notes) which dramatically reduces the opportunity for detection.

3. Smarter PLI reporting

Personal Location Information (PLI) is of critical use on the modern battlefield.  As a result, most military radios automatically transmit a soldier's GPS coordinates every two to five seconds. While this enhances situational awareness for commanders at headquarters, it also creates a constant RF beacon for enemy forces to detect.

An alternative option to this is adaptive PLI reporting. This adjusts the frequency of updates based on a soldier's movement. For example, if a unit is stationary, updates can be sent just once an hour rather than every few seconds, dramatically reducing their RF signature while still providing full tracking capabilities.

4. Frequency hopping & advanced waveforms

Traditional radios operate on a limited range of fixed frequencies, making them easy targets for enemy EW. Conversely, today’s fast frequency hopping radios can change channels up to 10,000 times per second, making it significantly harder for adversaries to detect transmissions.

Modern radios also typically fall into two camps - wide or narrow band.  While the former allows for large amounts of data transfer - such as direct video streaming - it also makes them more susceptible to detection due to the high-power use and adoption of a large band of frequencies. Narrowband radios don’t have these frailties but also don’t have all of the benefits of their wideband counterparts.  

Reducing the burden on soldiers

While LPD techniques are critical, expecting individual soldiers to manually manage all power levels, PLI reporting rates, and frequency hopping is unrealistic in high-stress combat situations.

The best communication systems integrate automated LPD measures, ensuring that soldiers can focus on their primary function - to fulfil their mission objective - without constantly thinking about and adjusting their radios. Next-generation communication systems must mitigate and handle these functions autonomously, adapting to threats in real time without requiring as much manual input.

The hybrid network approach: the smarter communication strategy

A further takeaway from recent conflicts is that not every soldier needs the same level of communication system. Many soldiers require only basic voice and data connectivity, while commanders may need higher-data-rate communications.

A hybrid frontline model - combining narrowband radios for most soldiers, with wideband solutions for commanders needing a wider view of the battlefield - offers the best of both worlds:

• Narrowband radios reduce RF exposure, minimising the risk of detection.
• Wideband solutions allow for higher-data transmissions, enabling additional information sharing and video feeds.

The need for action

As EW threats continue to evolve, forces that fail to adopt LPD principles will find themselves at increased risk on the battlefield.

The time to act is now. Leaders must ask themselves: are our soldiers able to communicate without being detected? If the answer is unknown, it's time to rethink your frontline communication strategies.

The battlefield has changed. Survivability now depends not just on strength, but on silence.

Talk to Thales to take action today.