Abstract: A system and method include a non-linear dynamic sensor, such as a magnetic field sensor, having an oscillator with a dynamic response that passes through a critical point beyond which the oscillator responds in an oscillatory regime. A processor operatively connected to the non-linear dynamic sensor is configured to, based upon an input signal x received by the non-linear dynamic sensor, adaptively self-tune the non-linear dynamic sensor to a dynamic range within the oscillatory regime adjacent to the critical point such that the input signal x spans the entire dynamic range. An array of such sensors includes a global feedback capability to mitigate coupling losses.

Abstract: A system that may be used for energy harvesting includes a flexible beam secured between a first support and a second support. The supports are spaced apart at a distance less than a length of the flexible beam such that the beam is buckled. Responsive to external vibrations the flexible beam switches between a first position and a second position. A magnetic proof mass is coupled to the flexible beam at the beam's midpoint. At least one permanent magnet is positioned proximate to the magnetic proof mass and has the same polarity. The permanent magnet is positioned to expose the magnetic proof mass to a repulsive force when the magnetic proof mass is located at both the first position and the second position. Piezoelectric transducers are located above and below the first and second positions of the flexible beam to harvest energy.

Abstract: The dynamics of a nonlinear sensor are configured to mimic threshold crossing dynamics of an integrate-fire neuron with negatively correlated inter-spike intervals. The configuration of the sensor results in a biomimetic sensor that provides results with an accuracy that mimic neuron sensing.

Abstract: A method for providing a biological logic gate comprising the following steps: subjecting a bistable autoregulatory gene network (GRN) to a noisy background; identifying adjustable parameters of the GRN; using logical stochastic resonance to determine values of the GRN parameters which result in the GRN performing different logic gate functions; and setting the parameter values of the GRN such that the GRN performs a first logic gate function.

Abstract: An ambient electric field detector comprising: a collection mechanism disposed to generate a current signal in response to the ambient electric field; an input current mirror operatively coupled to the collection mechanism and disposed to amplify and duplicate the current signal to generate a duplicate signal; and an odd number (i) of at least three nonlinear, over-damped, bi-stable elements coupled uni-directionally in a ring such that the ring of elements oscillates, wherein at least one of the elements has a different initial state than the other elements and each element is disposed to receive the duplicate signal.

Abstract: In various embodiments, an apparatus for detecting electric fields is disclosed that includes an array of non-linear elements configured into an oscillator with each coupled to one or more electric-field sensing plates. In various embodiments, an output of the array produces a frequency that varies as a function of an electric field sensed by the one or more electric-field sensing plates.

Abstract: A device includes a plurality of channel-capture circuits. Each circuit may include an array of N non-linear oscillators, wherein N?3, circularly connected to each other in series such that unidirectional signal flow occurs between the oscillators. Each circuit may be configured to capture a respective channel signal from a wideband signal containing a plurality of channel signals and convert its captured channel signal to a lower frequency. Each oscillator may include an oscillator input configured to receive an output signal from another oscillator, an oscillator output configured to provide an output for an input of another oscillator, a frequency capture input configured to receive at least a portion of the wideband signal, at least two amplifiers, and a control capacitor coupled to the output of the amplifiers. An analog-to-digital converter may be coupled to the output of each channel-capture circuit.

Abstract: An apparatus for sensing and processing a magnetic flux signal comprising: an odd number of at least three fluxgate modules, a summer, and a processor. Each fluxgate module is configured to generate a module response signal upon receiving the magnetic flux signal. The fluxgate modules are circularly coupled to each other such that only one-way signal flow is allowed between them. The summer is configured to sum the response signals from each fluxgate module into a summed signal. The processor is configured to receive and process the summed signal.

Abstract: In various embodiments, an apparatus for down-converting a first signal having a first frequency to a lower frequency is disclosed. The apparatus can include one or more arrays of N over-damped, bi-stable circuits unidirectionally-coupled from element to element.

Abstract: A target signal analyzer having at least one receiving antenna configured to receive the target signal, and a parallel array of oscillator rings. Each oscillator ring is operatively coupled to receive the target signal from the receiving antenna. Each oscillator ring has an odd number of at least three bistable, nonlinear oscillators circularly coupled to each other such that only one-way signal flow is allowed between the oscillators in each oscillator ring. Each of the oscillator rings is configured to oscillate and thereby produce a response signal only when the target signal frequency is within a designated frequency band. For every designated frequency band in a spectrum of interest, at least one of the oscillator rings is configured to produce a response signal.

Abstract: An apparatus for sensing and processing a magnetic flux signal comprising: an odd number of at least three fluxgate modules, a summer, and a processor. Each fluxgate module is configured to generate a module response signal upon receiving the magnetic flux signal. The fluxgate modules are circularly coupled to each other such that only one-way signal flow is allowed between them. The summer is configured to sum the response signals from each fluxgate module into a summed signal. The processor is configured to receive and process the summed signal.

Abstract: A coupled non-linear sensor system is provided for sensing a non-sinusoidal time-dependent target signal. The system comprises an odd number, other than one, of interconnected oscillatory sensors for sensing time-dependent changes in an external magnetic flux generated by the non-sinusoidal time-dependent target signal, the sensors coupled to each other by a coupling parameter characterized by a threshold value, so that each of the sensors oscillates in the presence of the non-sinusoidal time-dependent target signal as the coupling parameter exceeds the threshold value.

Abstract: A sensor system employing a plurality of nonlinear sensors utilizes a coupling network to interconnect the sensors wherein the coupling network inherently induces oscillations in the sensor system. This approach removes the need to provide bias signal generation either onboard the sensors or via a source external to the sensor.

Abstract: A method of estimating target signals (dc or low frequency signals) by a dynamical fluxgate sensor and a low-power fluxgate magnetometer operating according to the method. The sensor is pre-biased with a periodic bias signal in the form of a superposition of a square wave and a triangular wave. The change in residence time statistics in the stable state of the sensor is analyzed for estimating the target signals.

Abstract: An array of non-identical oscillators, driven by a common external driving force, is synchronized in phase. An example application is the phase synchronizing of non-identical vibratory gyroscopes to provide enhanced gyroscope sensitivity while minimizing the need for gyroscope proof mass alteration and individual gyroscope electronics.

Abstract: A method of estimating target signals (dc or low frequency signals) by a dynamical fluxgate sensor and a low-power fluxgate magnetometer operating according to the method. The sensor is pre-biased with a periodic bias signal in the form of a superposition of a square wave and a triangular wave. The change in residence time statistics in the stable state of the sensor is analyzed for estimating the target signals.

Abstract: A controlled stochastic resonance circuit applies stochastic resonance to bias a nonlinear device with a control signal having a selected amplitude, frequency, and phase to enhance or suppress the response of the device to a periodic signal embedded in noise.

Abstract: A signal processor utilizes a globally nonlinearly coupled array of nonlinear dynamic elements. In one embodiment of the invention, these elements take the form of bistable overdamped oscillators. The processor exploits the phenomenon of stochastic resonance to amplify a weak periodic signal embedded in noise. In this signal processor, a system or plurality of nonlinearly coupled overdamped oscillators is subject to a weak periodic signal embedded in a noise background. For communication or detection applications, this weak signal component is the signal of interest. A reference oscillator is chosen from the plurality of overdamped oscillators, and is given a time scale for relaxation that is longer than the remaining oscillators. The output of the reference oscillator is analyzed for signal processing purposes in response to the signal and noise.

Abstract: A stochastic resonator signal detector comprises a multi-stable nonlinear device for coupling to an input signal and a control signal coupled to the multi-stable nonlinear device for varying asymmetry among stable states of the multi-stable nonlinear device. The interaction of the input signal with the control signal in the multi-stable nonlinear device generates an output signal having an amplitude responsive to the input signal amplitude and a frequency range that comprises harmonics of products of the control signal and the input signal.

Abstract: The invention exploits the phenomenon of stochastic resonance in a nonlinear dynamic system to enhance the system's response to a weak periodic signal locally corrupted by background noise. The invention is designed to enhance the signal-to-noise ratio (SNR) in the system's output power spectrum at the periodic signal's frequency. This technique utilizes an array of nonlinear dynamic elements whose individual outputs are specifically coupled to other array elements. The coupling is found to substantially enhance the output SNR over what would be expected from a signal processor based upon a single such element. This principle has the potential to substantially enhance the performance of arrays of nonlinear devices; in fact, the nonlinear array can be expected to yield an output SNR that is very close to that obtainable by an array of ideal linear devices, so that the coupling actually "linearizes" the nonlinear system.