Temporally Advanced Signal Detection

Signal advance technology, implemented in electronic circuits, temporally advances the detection of analog waveforms. Our technology is based on Negative Group Delay, a wave propagation phenomenon. Temporal advance describes the ability to detect and analyze a signal earlier in time than can be accomplished using conventional electronics.

Overview – Technology

Sensors are used to detect various physical or physiological properties (e.g. pressure, temperature, speed, heart rate) and convert these properties into analog electrical signals. Typically, these signals are then digitized and processed to generate an output which can be used for monitoring, intervention, process control or similar functions.

Signal Advance technology acts to temporally advance the detection of these analog electrical signals and thereby offset or even eliminate circuit transmission and/or processing delays in responsive (control or interventional) systems. This technology can potentially improve the performance of a wide range of devices that process analog signals in areas such as industrial process control, interventional medical devices, alarm/detection systems, flight and vehicular control, as well as military targeting and weaponry.

In engines, this means that the combustion control system may respond more quickly to changes in engine demand such as acceleration of braking, thereby increasing fuel efficiency, proving more power and lowering emissions. In radar systems, earlier recognition of the radar “beam” bouncing from a followed object would result in earlier detection. In targeting systems, faster detection of changes in a targets position, velocity or acceleration of the target could improve targeting accuracy.

One of the most promising application areas (of which there are many) is that of medical intervention devices in which a small increase in signal detection time (on the order of fractions of a second) could have a major impact on the efficacy of the device and in some cases save lives. Potential applications include seizure detection, cardiac rhythm management, neuroprosthetics, neurotherapy, gated imaging and radiotherapy.

Proprietary Signal Advance (SA) circuitry operates on broadband analog signals (over a specified frequency range) and can be designed to produce minimal distortion in the circuit output relative to its input. SA has developed a number prototype of SA circuit designs that operate over various frequency ranges. Circuit transfer functions have been analyzed and their performance modeled and the circuit designs have been tested using a range of test signals.

In state-of-the-art interventional medical or industrial devices, time delays due to signal detection, processing and generating a response reduce the likelihood of successful intervention. This applies, for instance, to containing or limiting a life-threatening patho-physiological event such as cardiac ventricular fibrillation or an epileptic seizure. The earlier the intervention is initiated, the greater the chance for successful remediation.

Currently, hybrid predictive feedback and feed-forward control systems are used to improve control response performance. Approaches to improving systems that rely on increasingly faster electronics can reduce, but never completely eliminate, these delays, nor provide a net temporal advance. SAT achieves the latter by exploiting ‘negative group delay’, a somewhat counterintuitive, yet empirically verified, wave propagation phenomenon in physics.

In most electronic circuits, the output signal is typically delayed relative to the input. In a circuit exhibiting a negative group delay, the output signal is advanced in time relative to the input, thus the term ‘signal advance’. The temporal advance achieved using SAT can potentially offset signal detection and processing delays.

Current approaches to improving the performance of signal transmission and responsive systems rely solely on the development of increasingly faster electronics that can reduce the total time delay through the device but not eliminate it entirely nor provide a net temporal advance. In addition, hybrid predictive feedback and feed-forward control systems (typically implemented digitally) are employed to improve signal response performance. These approaches may be adequate for a number of control systems

 DIfferSAT however, achieves performance improvements using unique, engineering-physics based technology implemented in analog circuitry. By reducing or eliminating signal detection and processing delays, this technology improves the performance of a wide variety of biomedical and industrial intervention and control systems. Success in this endeavor has potential application across a broad range of systems that rely on the detection of a wide variety of analog signals and may in turn lead to a new class of proactive rather than reactive intervention and control. In addition, SAT can be applied in conjunction with these conventional methods to further improve system performance.