Open summary
- KNL is the first to bring staring ALE to a field-deployable manpack, delivering 0.5-second link establishment and wideband HF communications up to 300 kbit/s with just one day of operator training.
- Staring ALE continuously monitors over 4,000 HF channels simultaneously, replacing advance frequency planning and manual selection with real-time automatic frequency planning.
- Unlike scanning systems limited to a small pre-assigned pool, KNL's CNHF radio treats the HF spectrum as a shared, dynamic resource and instantly selects the best clear channel at the moment of transmission.
- Dynamic, unpredictable frequency selection makes the radios extremely difficult to jam or intercept, while keeping them fully operational in GNSS-denied environments without time synchronisation.
A fast, reliable connection without worrying whether your designated HF frequency is free and uninterrupted at the critical moment. That’s the scenario every operator wants.
In KNL’s cognitive networked HF radio (CNHF) system, this scenario is achievable without prior frequency planning, thanks to our advanced staring ALE (Automatic Link Establishment) technology. Instead of predicting the future, our radios observe the present: continuously and simultaneously across the entire HF spectrum.
Staring ALE removes the burden of manual frequency selection, enabling real-time, automatic frequency planning. If conditions change during data transfer, the radio automatically switches to another frequency without users across the CNHF network ever noticing.
In this blog post, we cover the key benefits staring ALE brings to HF radio communications. How does staring ALE benefit operators in the field? How can staring link establishment be utilised in a military manpack?
Read also: Automatic link establishment in 0.5 seconds – discover why KNL’s ALE HF radio outperforms others
Staring ALE has long been discussed as the future of HF communications. While multi-channel staring receivers have entered the market, KNL is the first to fully realise this concept. With over 4,000 simultaneous channels, our solution sets a new benchmark in the industry.
What is Staring ALE?
- There are two ways a radio can search for a suitable frequency to establish a link: scanning or staring.
- A scanning radio scans frequencies one at a time. A staring receiver listens to a large number of channels simultaneously, without interruptions.
- A staring radio, like KNL’s CNHF radio, goes further. It not only listens to thousands of channels simultaneously but also uses this capability to establish and maintain links automatically, switching between frequencies seamlessly.
- The CNHF system uses advanced staring ALE technology for link establishment.
- KNL’s staring ALE enables a far wider spectrum usage than legacy HF systems, ensuring the best available channel is always found.
- The radio observes the real-time state of the spectrum and selects the best available channel automatically.
- With staring link establishment, data transfer can begin on any frequency at any moment, with no requirement for time synchronisation.
Staring ALE radio captures the right frequency at the right moment
Traditional scanning ALE systems operate within a limited pool of available frequencies, typically ranging from a few to several dozen, that must be carefully coordinated in advance.
In contrast, KNL’s staring ALE radio continuously monitors broad sections of the HF spectrum, so the same frequency bands can be actively shared across many users. At the moment of transmission, the radio selects the optimal available channel automatically, without any user intervention.
Instead of locking down spectrum that sits idle much of the time, KNL’s staring ALE radios treat the HF band as a shared, dynamic resource that is fully utilised.
KNL’s staring ALE radio
Staring ALE avoids interference and reserved spectrum effectively
Within NATO and partner nations, frequency assignments are coordinated in advance. National forces operate on certain bands, allied forces on others. Adversaries, however, operate outside these arrangements. A pre-assigned frequency will be targeted, can be occupied, or be disrupted by environmental conditions. If the radio is committed to that frequency, communication is compromised.
As explored earlier in this blog, in KNL’s cognitive system the staring link establishment selects the best available channel at the exact moment communication is needed, moving to a clear frequency automatically and without operator input. In practice, these capabilities make our radios extremely difficult to jam or intercept.
Additional features such as ECCM (Electronic Counter-Countermeasures), robust mode, and multihop networking further strengthen the anti-jamming capabilities of our radios, even when operating in the most heavily contested environments.
Read also our previous blog about how cognitive radios ensure anti-jam communication.
By selecting only frequencies that are clear at the point of transmission, KNL’s staring ALE also avoids interfering with friendly traffic, ensuring clean and efficient use of the spectrum across the entire network.
The operational benefits of KNL’s staring ale
- Uninterrupted connectivity in the most challenging conditions. If interference is detected, the radio switches to a clear frequency in milliseconds, without any break in communication.
- No HF expertise required. Staring ALE selects the best available channel in real time enabling effective use by any operator, regardless of their HF expertise.
- Fully operational in GNSS-denied environments. Staring link establishment requires no time synchronisation, keeping KNL’s radios functional even when GNSS signals are jammed or unavailable.
- Low probability of interception. Frequency selection is dynamic and unpredictable, making it extremely difficult for adversaries to target communications.
- Efficient spectrum sharing. Multiple users can operate across the same frequency bands simultaneously as the radio selects whichever channel is free at the moment of transmission.
Implementing staring ALE to a manpack radio is a significant step forward
KNL’s CNHF solution digitises the entire HF frequency range, enabling a large number of receivers to operate simultaneously and switch frequencies at speed. The patented, fully digital receiver architecture makes it possible to implement KNL’s staring ALE technology also on a portable device.
Engineered for maximum security, resilience, and reliability, the CNHF Manpack brings staring ALE capabilities directly to the operator in the field.
The CNHF Manpack uses a Cognitive Networked HF Waveform that intelligently navigates real-time environmental variables without relying on radio frequency planning and channel predictions. It supports wideband HF communications up to 300 kbit/s across diverse media formats without performance loss regardless of the number of network nodes. Encrypted voice and data ensure no transmission is compromised, while the user-friendly design allows for full operational fluency with just one day of training.
Read also: Transforming critical communications through intelligent frequency selection
KNL is the first to implement staring ALE in a field-deployable manpack. The rapid 0.5 sec link establishment and listening over 4,000 channels simultaneously is a significant technical accomplishment in a portable device.
The CNHF Manpack
Effective spectrum use with staring ALE takes a modern mindset on frequency planning
Staring ALE does not just change how HF radios operate. While it enables more versatile use of the spectrum, it requires a mindset shift in how we think about frequency planning.
Traditional frequency planning is built on a simple premise: dedicate specific, narrow frequency bands to specific users/use cases and secure them. In practice, this means large portions of the HF spectrum are reserved but rarely used.
The HF spectrum is a finite resource. In the frequency dimension, it is crowded. But in the time dimension, it is far from full. Many reserved frequencies go unused for hours or days at a time.
As Rickard Berg and Jonas Mentzer state in their conference publication Spectrum sharing in four dimensions, the traditional way of assigning frequencies as primary user is very ill suited if the intention for the user is to use modern HF technology to its maximum capacity, both in terms of bandwidth and propagation.
If one adds military aspects such as the threat of signal intelligence and electronic warfare, a more flexible approach to spectrum sharing appears much more appealing, they continue. Effective spectrum management, they conclude, is crucial to meet the growing demand for robust communication within the HF domain (Berg & Mentzer, 2025).
To ensure efficient spectrum use, frequency planning should be approached from a new perspective. Instead of tightly reserving specific frequencies, the focus should be on what modern technology enables for more effective spectrum utilisation and how the widespread adoption of these technologies can best be supported.
Modern, highly automated and secure systems, such as KNL’s CNHF radios, take care of all the complexity traditionally associated with HF radios, and do this without any user intervention. CNHF radios with staring ALE select the best available frequency in real time, avoid interference, and adapt continuously as conditions change.
Effective use of the HF spectrum means trusting modern, automatic systems to do what they are designed to do: select the best available frequency in real time, avoid interference, resist jamming and adapt continuously as conditions change.
Get Connected with Staring ALE
KNL is committed to delivering cutting-edge BLOS communications for defence, military, and security organisations worldwide. Whatever direction staring ALE technology develops, KNL will be at the forefront.
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This article has utilised background material from interviews with KNL experts and a conference publication: Berg, R. & Mentzer, J. (2025). Spectrum sharing in four dimensions. Proceedings of the Nordic HF Conference HF 25, p. 7.3.2.
