Will the Special Forces be able to identify the bad guys through their heartbeat?

I was writing, in an older article, that within terrorism prevention and counteraction or the fight against organized crime, the biometric data, along with other criminal investigation methods, can decisively help the investigators, attorneys or analysts to establish the individual profile and establish connections between a certain individual (for example, terrorist, criminal, insurgent etc.) and different activities, events, places, objects or interested people.

In the operational planning process, such identified, monitored, tracked and influenced intelligence individual or that is the targeting management process object, for various reasons, can turn into a priority on the High Value Target list (HVT). From that moment on, it can be planned and executed a deliberated special operation (counterterrorist, for example) to eliminate or capture him. I have offered here more information about the execution of such operation by the Special Forces (raid).

In order to make sure the decision to attack (commit), lethal or non-lethal, such a human target (humanitarian international right, human’s fundamental rights imposed by national legislation, other active national laws, rules to commit into a fight), to avoid collateral victims and increase the success of such mission, the Special Forces must first positively identify such human target (Positive Identification- PID) and be highly certain about it.

In other words, Positive Identification is the reasonable certainty that the designated target is the legitimate military target and not someone else. The operation can be made by observing and analyzing target’s characteristics, using different reconnaissance technologies and techniques, such as those based on biometric data collection. During the execution of a high-risk special operation, any remote and contactless reconnaissance technology of a target helps its positive identification by the Special Forces operator who is in the tactical field.

The heartbeat- biometric signature

Research made during the past decades has revealed that heartbeats have important information about the individual, his emotional condition (anxiety level, for example), his cardiac condition and even his personality features, being, practically, a distinct “signature”, different from individual to individual. It is a certain pattern of electric potential variation, which is created on human body’s surface, thanks to his cardiac activity. It can be recorded even as graphic waves, through an electrocardiogram and describes physiological features and individual behaviours.

These are biometric data, just like the digital fingerprints, face structure, iris model, retina model, vocal hallmark or DNA data and can be used, independently or collectively, to verify or recognize the identity of a human being, but also to establish certain connections between an individual and certain information.

Although these biometric “signatures” are unique and can hardly be identified, some researchers think that, however, one individual’s EKG can change due to his physical activity, medication and substances tracking the cardiac rate, stress, age or other factors. Currently, they are working on improving some algorithms to correct such variations.

Remote collection technologies for heartbeat’s “signature”

As for heartbeats, recent technologies allow data collection also remotely. This is made through some laser beams able to measure vibrations, using the so-called Doppler effect (the frequency variation of a wave issued by a vibrations/ oscillations source, if that is in motion from the receiver). The laser vibrometer used in the industry to measure, contactless, the vibration of different bodies or objects follows the same principle.

What’s the Doppler laser vibrometer and how does it work?

Doppler vibrometer is composed of a monochromatic beam laser and an interferometer (an optical device that measures through interference), which detects the light modification of the laser light frequency then reflected by a surface in motion (which vibrates).

The interferometer divides the light in two parts: a reference beam which is directed towards a photodetector and a beam directed to the target. On this target, the light is reflected back, as a wave, by surface’s motion. Depending on the motion parameters of the target, the light is reflected back with modified frequency and phase. The photodetector overlaps this light with the reference beam, creating an output signal which is the Doppler modification in frequency (between the issued signal and the received one). The processing and analysis of this signal provides the vibration speed and the motion of the target.

The detection devices of vehicles’ speed (known as “radar”), used by highway patrol in monitoring the public streets circulation, are using a similar functioning principle.

The biometric identification through heartbeat signal – current limitations

Biometric identification involves two phases: recording based on biometric data (individual biometric signature to be collected and achieved for ulterior uses) and authentication (comparing the existent biometric signature sample in databases with biometric signature collected during authentication or validation or not, with a higher probability or identity).

From the very beginning, the possible use of a device for remote identification of human target’s cardiac signature implies the existence of a database wherein such signatures have been registered, but also the access to it. Both are quite difficult to achieve in a timely manner due to the existence or not of the data and the legitimacy of their management.

For example, in our country, even if, for example, we assume that such a database would exist somewhere, centralized, and even if it would be enough comprehensive, the access to such personal data is restricted by law. For example, the Law of Patient Rights no. 46 of January 21, 2003, states that "all information regarding the patient's condition, results of investigations, diagnosis, prognosis, treatment, personal data are confidential even after his death", and they can be provided only if the patient gives his explicit consent or if expressly required by law.

Moreover, in the work of Israel, S.A. and Irvine, J.M. (2012) "Heartbeat biometrics: a sensing system perspective", Int. J. Cognitive Biometrics, Vol. 1, No. 1, pp. 39-65, the authors identify some important limitations of heartbeat biometrics that should be overcome before operational use. It is about the current low information content necessary to identify a reasonable number of individuals, the long time needed to keep the measurement sensor on target in order to collect a sufficient number of information needed to identify the person, the emotional state influence on the measurement result, the measurements dependence on the technique used and sensor’s position on the body, the environment influence and the cardiac events’ significant impact and of individual's health on the cardiac signature.   

What technologies and systems will the American Special Forces use?

Despite the aforementioned limitations and doubts about the efficacy of currently using cardiac biometrics in human targets’ positive identification, US Special Forces have called on the Pentagon to develop technology and systems that will be able to solve such a problem, even without seeing individual’s face. This is the Jetson system, capable of measuring, from a maximum of 200 meters away, the clothing minimum vibrations by the beats of one's heart.  

The system was developed with the help of an American private company that develops and integrates state-of-the-art biometric systems for the Pentagon and has provided Special Forces, present at the Afghanistan theatre, biometric devices for the secure recording of SEEK II biometric data that I have wrote about some time ago.

According to an article published last year in the journal of Massachusetts Institute of Technology (MIT), Jetson is practically a commercial laser vibrometer (similar to the one presented above, but apparently with infrared light) that has been fitted with a stabilizer holder to maintain the fixed laser spot position on the target and has been adapted to record heartbeat even through clothes (not very thick - shirt, jacket). Due to the algorithms used to extract the cardiac signature from laser signals, it appears that Jetson can achieve over 95% accuracy under optimal conditions, and this can be further improved.

One of its major limitations is target’s need to stand still or sit for 30 seconds, the minimum time required to collect the cardiac signature. In contrast, the operating environment wherein the special operations are carried out is usually in a continuous dynamic and is characterized by extreme risks and uncertainty. A target that feels or suspects that it is being pursued and supervised in the external environment can hardly give himself/herself in. On the contrary, he/she will take all necessary countermeasures to mask, deceive and avoid direct engagement with the adversary, but also counter-response to ensure their survival or freedom of movement.

Instead of conclusions

In practice, the face recognition is the method used for remote biometric identification, which involves have a good frontal view to the target, and the human target to wear no mask, beard, sunglasses or hats. Here is where another complexity of the operational environment and technological capabilities comes in, usually raising obstacles. A system like Jetson, also used collectively, may improve the ability of human targets’ positive identification operations’ efficacy, executed by Special Forces during special operations, together with facial identification or other identification methods.

But, again, having something to compare the data collected in the field with needs access to a database which should exist and be enough complex when it comes to personal data of different possible bad guys, having records, but also of those who have no records, though posses unorthodox behaviour.

One thing is for sure. From now on, the bad guys will be identified also through their heartbeats. Remotely, with no one there saying: let me check your heartbeat so that I can tell you what kind of person you are. Indeed, only if they will not play the...dead... for 30 seconds.

Translated by Andreea Soare