Abstract: A training method provides an advantageous technique for estimating secondary propagation path parameters based on learning propagation path characteristics for a selected number of secondary propagation path signals. In a multipath environment, a received radio signal comprises multiple received signals, each received through a different signal propagation path. The strongest multipath signal is deemed the main path signal, while the remaining multipath signals are termed secondary path signals. In some types of direct-sequence, spread spectrum communications systems, significant secondary signals must be canceled from the received multipath signal to achieve desired receiver performance, while in other types of systems, such secondary signals may be used to enhance the signal-to-noise ratio of the received signal. In either case, the various multipath signals must be accurately characterized.

Abstract: An exemplary system for measuring noise in a device comprises a CPU, a memory coupled to the CPU, an interface coupled to the CPU for providing instructions processed by the CPU, a control unit coupled to the interface for receiving the instructions, a preamplifier circuit coupled to the control unit for implementing the instructions, a power supply unit controlled by the control unit for providing power to the preamplifier circuit, and a device holder selectively attached to the preamplifier circuit. In an exemplary embodiment, the preamplifier circuit further comprises a plurality of filters, an amplifier circuit, a plurality of switches for switching the amplifier circuit between a voltage amplifier mode and a current amplifier mode, and a variable loading resistor.

Abstract: According to one embodiment of the present invention, a system (100) for measuring overall jitter is disclosed that includes a data converter (102) that measures a signal to generate a first measurement set (212) and a second measurement set (214), which are used to compute overall jitter. According to one embodiment of the present invention, a method for measuring overall jitter is disclosed. The data converter (102) generates the first measurement set (212) and the second measurement set (214) by measuring the signal. The overall jitter is computed using the measurement sets (212 and 214). According to one embodiment of the present invention, a system (400) for measuring internal jitter is disclosed that includes a splitter (404) that splits a signal into an input signal (406) and a clock signal (410). The data converter (102) measures the input signal (406) to generate a first data set and a second data set, which are used to compute the internal jitter of the data converter (102).

Abstract: A apparatus for computing coefficient values for configuring a digital filter for compensating for non-linearity of an RF/IF device. The apparatus includes a reference signal generator, connected to an input of the RF/IF device, for generating an input reference signal to the RF/IF device. A vector signal analyzer, connected to an output of the RF/IF device, analyzes a response signal from the RF/IF device and outputs digital in-phase and quadrature-phase (I/Q) signals. A processor, connected to an output of said vector signal analyzer, computes a difference between the input reference signal and the digital in-phase and quadrature-phase (I/Q) signals. The processor calculates the coefficient values for configuring the digital filter based on the computed difference. A memory device, connected to the digital filter, stores the calculated coefficient values for the digital filter.

Abstract: A leakage detector includes a receiver front end having an input for connection with an antenna and a signal path including circuitry for passing a signal from the input without amplification; an IF stage connected with the receiver front end for producing an IF signal therefrom; a detector for producing an AM detected output signal in response to the IF signal; a leak processor for passing only a synchronizing signal of the AM detected output signal, along with harmonic frequencies of the synchronizing signal and DC signals, the synchronizing signal having a peak level, and the signal processor providing an output corresponding to the peak level of the synchronizing signal of the AM detected output signal; a display; and a processing unit connected with the leak processor and the display for displaying leakage data in response to the output signal from the leak processor.

Abstract: A method and apparatus of measuring current in a switching circuit (2) of the two-port type having a first set of terminals connected to a set of terminals of a noise reducing circuit, wherein a second set of terminals of the switching circuit has a switching terminal, which is adapted to be switched between the set of terminals of the noise reducing circuit, including the steps of providing an impedance in parallel with the switching circuit; measuring a current as a transient measurement during switching sequences in the switching circuit, the measurement being performed across an impedance in the noise reducing circuit.

Abstract: A method and an apparatus for detecting signals in an electromagnetically noisy environment by detecting electromagnetic signals comprising a noise signal and a known signal, and compressing the electromagnetic signal to thereby generate a compressed signal. The compressed signal is filtered to generate a filtered signal comprising substantially the known signal, and the filtered signal is expanded.

Abstract: A testing device generates electromagnetic noise such as transients, power interruptions and Radio Frequency Interference (RFI) for application to an electronic device to test the immunity of the electronic device to electromagnetic noise or to test the performance of the electronic device during exposure to electromagnetic noise. The testing device promotes an economical and efficient evaluation of Electromagnetic Compatibility (EMC) of an electronic device during product design or otherwise. The testing device includes a switch having electrical contacts for producing electromagnetic noise during a transition between a closed state and an open state of the electrical contacts and a trigger that is coupled to the switch. The trigger is arranged to change states between the closed state and the open state of the electrical contact. An input terminal is associated with the switch for applying electrical energy to the switch.

Abstract: The invention is a multipath meter that analyses estimates of parameters associated with a direct signal component and one or more multipath signal components of a signal received by an antenna. The meter analyses the parameter estimates in order to facilitate the select of a location for an antenna, monitor signal quality at an existing antenna site, and/or to determine if satellite failure or some other type of signal failure has occurred. The multipath meter makes available to a user or for analysis information related to the contributions of the direct signal and the multipath signals to the received signal. The information includes estimates of various parameters such as delay, relative amplitude and phase of the direct and multipath signals. The meter calculates a ratio of the amplitudes of the direct and the multipath signals, to determine the severity of the multipath signals and, thus, the signal quality.

Abstract: In a signal reproduction block of a DVD reproduction apparatus, an output signal line for outputting a characteristic information signal representing a characteristic of a filter incorporated in the signal reproduction block to the outside is additionally provided on the output side of an A/D converter. In this way, it is possible to prevent an analog data signal from deteriorating during a data signal reproduction process due to a parasitic effect of the output signal line. Moreover, the filter characteristic information signal is output through the output signal line after it is converted to a digital signal by the A/D converter, thereby avoiding the deterioration the characteristic information signal and thus improving the measurement precision.

Abstract: The phase noise of an oscillator described by a known set of differential algebraic equations (DAEs) can be predicted by a) finding the steady state waveform of the oscillator, e.g., by using harmonic balance techniques or so-called “shooting” techniques, either of which involves developing a mathematical quantity known as the augmented Jacobian matrix; b) solving a prescribed linear system of equations that uses the augmented Jacobian matrix, the solution being called a perturbation projection vector (PPV), c) plotting a graph of the phase noise of the oscillator as a Lorentzian function of the solution of the prescribed linear system of equations. The prescribed linear system of equations which is used is the system of equations formed by setting a matrix product equal to a unit vector.

Abstract: A vector network analyzer (VNA) is provided with three test ports and an integration of hardware and software to make an integrated set of measurements for two and three port devices. The integrated capability allows for fast, versatile measurements that benefits, in accuracy and convenience, from sharing of data and resources with other measurements. The VNA includes a first signal source which is selectively connectable through reflectometers to two of the three VNA test ports. A second signal source provides connection through a third reflectometer to a third test port to enable full vector error corrected 3-port S-parameters measurements to be made. The two signal sources, along with software configuration of the VNA to operate in a non-ratioed mode provides for measuring second and third order intercept measurements. The two signal sources and software also enable the VNA to be used to make frequency translation measurements of a mixer including accurate frequency translation group delay measurements.

Abstract: A fault and noise tolerant system and method for obtaining an original signal which is not influenced by a fault or noise occurring in an electronic equipment. The fault and noise tolerant system includes a first estimation filter for estimating an original signal from a signal output from the electronic equipment, considering noise of the electronic equipment; a second estimation filter for estimating the original signal and a fault signal from the signal output from the electronic equipment, considering a fault and the noise; a fault detection unit for detecting the presence or absence of a fault in the electronic equipment based on the estimated fault signal received from the second estimation filter; and a selection unit for selecting one of the estimated original signals from the first and second estimation filters, respectively, according to the result of detection of the fault detection unit.

Abstract: The object of the present invention is to provide an electromagnetic noise measurement apparatus, electromagnetic noise measurement method and recording medium capable of preventing erroneous measurement of electromagnetic noise and of enhancing measurement efficiency. An electromagnetic noise measurement apparatus includes a PC, a field intensity meter, a spectrum analyzer, a preamplifier, a controller, a printer and the like. The controller is connected to a turn table for turning an electromagnetic noise measurement target, e.g., a copying machine, and to an antenna elevator for elevating an antenna for measuring electromagnetic noise radiated from the copying machine. The controller controls the turn table and the antenna elevator according to command of the PC. The PC compares a QP value acquired by the field intensity meter with a peak level acquired by the spectrum analyzer, and displays an error message if the difference between the QP value and the peak level is large.

Abstract: A method and apparatus for frequency domain noise analysis that uses moment matching techniques and reciprocity to provide efficient noise analysis without the need for one analysis per attacker and without resorting to pruning techniques and their concommitant error.

Abstract: A method and apparatus for frequency domain noise analysis that uses moment matching techniques and reciprocity to provide efficient noise analysis without the need for one analysis per attacker and without resorting to pruning techniques and their concommitant error.

Abstract: A plurality of battery-operated transceivers encapsulated by lamination to form a sheet of independent transceivers is tested in a two piece fixture that forms an enclosure surrounding each in-sheet transceiver. Each enclosure has an antenna for transmitting a command signal to the transceiver at a known power level and for receiving a reply message from the transceiver containing a power level measurement made by the transceiver. Test methods using the fixture of the present invention are also described.

Abstract: A phase noise measurement method including a low noise programmable synthesizer and a receiver/down converter is provided. The low noise synthesizer provides L-Band Signals which can selectively exhibit low noise close-in or low noise far out. The receiver/down converter provides for absolute, additive, and down converted/direct/multiple phase noise measurement.

Abstract: Configurable interconnect resources of field programmable gate arrays (FPGA's) are tested by configuring at least some of the lookup tables (LUT's), registers and input signal acquirers to implement one or more sequential state machines that feed back their current states via at least some of the interconnect conductors to the inputs of the LUT's. The fedback signals are decoded by the LUT's for defining next-states of the one or more sequential state machines. Each sequential state machine may be programmed to sequentially step through a number of unique states, where the unique states challenge capabilities of the interconnect conductors to toggle through combinations of different signal levels. The sequential state machines are exercised to sequentially step through plural ones of their unique states.

Abstract: A circuit includes an integrator arranged to integrate input signals over a predetermined sample period based on the cycle period of a power source signal. A delay is coupled to the integrator and is responsive to the end of a sample period to delay start of a successive sample period for a predetermined time delay to cancel low frequency noise induced into the circuit during a prior sample period.

Abstract: A method and apparatus for allocating decoupling capacitance in a power grid is provided. A power grid model of an RLC network is evaluated to identify the power nodes that have peak voltages exceeding a minimum voltage threshold and a maximum voltage threshold. For each noisy node that violates the thresholds, a decoupling capacitor is inserted. The power grid is once again re-evaluated to determine of any of the power nodes still violate the voltage thresholds. For those violating power nodes, the size of the decoupling capacitor is incremented. This process of incrementing the size of the decoupling capacitance and re-evaluating the power grid is repeated until all the power nodes are within a noise budget or the noise level for each power node is within the thresholds. The decoupling capacitance is then re-evaluated as it is iteratively decremented while maintaining the power noise within the thresholds.

Abstract: The invention relates to a method and a measuring arrangement for measuring the gas content of a fluid (13). The fluid (13) comprises gas bubbles. In the method, microwave radiation (20) is transmitted through the fluid (13) and a signal (7) indicating the travel time, phase or amplitude of the radiation (20) is formed in a microwave measuring device (16), and a gas measuring equipment (18) determines the gas content of the fluid (13) by means of the signal (7).

Abstract: A method and apparatus for determining EMI compliance provides a conductor that is mutually impedance coupled to an integrated circuit on a semiconductor package. The conductor is attached to a lid covering the integrated circuit and RF noise energy on the lid is mutually impedance coupled to the conductor. By measuring the voltage at the conductor, an indirect measurement of the EMI generated by the integrated circuit is made.

Abstract: The power supply of equipment being tested for common mode noise problems is connected to a source of power with the power and neutral input terminals of the power supply isolated from the power ground. Recorded common mode noise signals are then inserted between the power supply's neutral input terminal and power ground to produce problem conditions. When the cause of the problem conditions are identified, steps are taken to eliminate the condition.

Abstract: The present invention discloses a dynamic period detecting method and detector, which utilizes a zero-crossing detecting method to detect a rough estimated period and then uses a weighting-average filtering method to eliminate noises to obtain an accurate period P. Since the average number for generating weight in the weighting-average filtering method is dynamically adjusted according to the period variation, the detecting method can detect the period correctly and fast, and save a lot of storage space and computation time.

Abstract: An apparatus and method is disclosed for measuring and filtering noise signals in an active video signal to create an enhanced video signal that produces a video image that is subjectively perceived to be superior to prior art video images. The apparatus of the invention comprises (1) a filter for filtering frequency components of a video signal, and (2) an absolute value unit for calculating the absolute value of pixels in the filtered video signal, and (3) a clipping unit for clipping the absolute values of the pixels to a threshold value related to subjective human perception abilities, and (4) a summer circuit for summing the values of the clipped signals for pixels that are located within a sliding window, where the sliding window is sequentially located in different areas of a frame of the video image, and (5) a detector for detecting at least one minimum sum of the clipped absolute values of the pixels that is indicative of the noise in the video signal of the video image.

Abstract: A module for use in automatic test equipment is disclosed. The module is especially useful for measuring noise parameters of high frequency devices. The module includes a noise generator and a plurality of EEPROM's that store reflection coefficients and ENR data for the noise generator. Computerized control circuitry in the automatic test equipment uses the stored data to reduce impedance mismatch and Excess Noise Ratio (ENR) data uncertainties in the measured noise parameters.

Abstract: A first substrate having a first electromagnetic noise sensor on its surface perpendicularly intersects with a second substrate having a second electromagnetic noise sensor on its surface, making up an integral structure. A first induced voltage value output from the first electromagnetic sensor at a position thereof directly before driving by a driving means is recorded, and a second induced voltage value output from the second electromagnetic noise sensor at a position thereof at a time of movement of the integral structure for only a predetermined distance by a driving means is recorded. Further, the first and second electromagnetic noise sensors are parallel connected at the position of movement, and a third induced voltage value output from a parallel connected electromagnetic noise sensor is also recorded. Based on the recorded first and second voltage values, an electromagnetic noise level in a vicinity of the integral substrate is determined.

Abstract: Noise detection devices are placed at arbitrary measurement points. A selection device switches the output of the noise detection devices and an analyzer analyzes the noise amount of the frequency component for each frequency band of radiated noise. A comparison device is made up of a storage section for storing measurement data provided by a plurality of the detection devices and a comparator, and finds a difference and a greater-than, equal-to, or less-than relationship between the noise amount analyzed by the analyzer and a predetermined value in a full band or at a specific frequency or a difference and a greater-than, equal-to, or less-than relationship between the noise amounts at two points. Output of the comparison device is displayed on a display device.

Abstract: A noise detecting and recording apparatus which can be widely used for countermeasures against malfunction of electronic equipment which is caused by noises is provided. The apparatus is provided with a unit for outputting data corresponding to the level of a conduction noise, a unit for outputting the data corresponding to the level of a radiation electromagnetic field noise, a unit for outputting the data corresponding to the level of a discharge noise, a temperature and humidity detection unit for detecting temperature and humidity and outputting the data corresponding to the detected value, a microcomputer for processing the output data from each unit, a display unit for displaying the output data, and a recording device for recording data, wherein the microcomputer performs the processing of receiving the output data from each unit and supplying the data to the display unit, and the processing of receiving the output data from each unit and recording the data in the recording device.

Abstract: A device for detecting electromagnetic stray effects in systems with at least two inductive sensors which provide an essentially periodic output signal, performs a signal evaluation for evaluating signals of the sensors, a test for detecting an electromagnetic stray effect, whether periods of the signals to be evaluated lie within a period length of expected stray effects, a test, if applicable, whether detected signal progressions have at least a progression typical for stray pick-up, plausibility tests by means of at least one further detected signal in which a signal to be checked is compared with parallel measured other signals, and detecting a stray effect only if all tested conditions provide a result which is typical for stray effects.

Abstract: A phase noise measurement system including a low noise programmable synthesizer and a receiver/down converter is provided. The low noise synthesizer provides L-Band Signals which can selectively exhibit low noise close-in or low noise far out. The receiver down converter provides for absolute, additive, and down converted/direct/multiple phase noise measurement.

Abstract: The breakdown of an ultra-thin dielectric layer is detected by applying a test signal to the layer. Measurements are taken of noise signals present in the layer during the application of the test signal. At breakdown, a significant increase occurs in the amplitude of the measured noise signals. Similarly, fluctuations in quiescent current, I.sub.DDQ, (I.sub.DDQ noise signals), rather than the values of I.sub.DDQ, are utilized during testing as the basis for detecting defects in integrated circuits.

Abstract: Robust Vibration Suppression methods and systems providing improved robustness range and are effective in single or multiple degree of freedom systems are disclosed. Methods disclosed include providing an output response from a physical system by selecting a command input to be applied to a physical system based on robustness and/or noise generation potential as determined by analyzing the acceleration frequency spectra of the command inputs. Also disclosed are specific robust command inputs and methods for deriving new robust command inputs.

Abstract: A surface potential sensor which is less affected by noise superposed on a reference source voltage than prior sensors, and hence can improve measurement accuracy with ease, and which also has higher stability against extraneous noise. The sensor includes an initial-stage input circuit comprising an FET, and a succeeding-stage amplifier circuit mainly comprising an operational amplifier for amplifying a difference between an AC component from the initial-stage input circuit and a reference source voltage. A resistor is connected between a drain of the FET constituting the initial-stage input circuit and a source voltage line to take out a signal from the FET drain. The source voltage supplied to the FET is the reference source voltage.

Abstract: A method and apparatus for measuring electrical noise in devices is disclosed that comprises two distinct measurement phases. In one phase, the differential output resistance, r.sub.ab, between a first terminal, a, and a second terminal, b, of the device under test is measured. In the second phase, a voltage, V.sub.L (t), is measured across a load resistance, R.sub.L, that is in series with the first terminal, a, of the device under test. Then the output voltage noise spectral density, S.sub.VL, is determined based on a fourier transform of the voltage, V.sub.L (t); and the output current noise spectral density, S.sub.ia, is determined based on the output voltage noise spectral density, S.sub.VL, the load resistance, R.sub.L, and the differential output resistance, r.sub.ab.

Abstract: A phase noise measurement system including a low noise programmable synthesizer and a receiver/down converter is provided. The low noise synthesizer provides L-Band Signals which can selectively exhibit low noise close-in or low noise far out. The receiver down converter provides for absolute, additive, and down converted/direct/multiple phase noise measurement.

Abstract: A method for measuring interference in a cable transmission system includes the step of establishing a spectrum frequency measurement window having start and stop frequencies and an amplitude threshold. Data is acquired over the window representative of the spectral energy of the cable transmission system within the window and the data is compared against the threshold value. If the data falls below the threshold value, indicating the absence of a carrier signal within the window, a display is generated characterizing the interference over the window. Additional measurement windows may be established having different start and stop frequencies and thresholds for measuring different portions of the cable transmission system frequency spectrum.

Abstract: The breakdown of an ultra-thin dielectric layer is detected by applying a test signal to the layer. Measurements are taken of noise signals present in the layer during the application of the test signal. At breakdown, a significant increase occurs in the amplitude of the measured noise signals.

Abstract: A method and apparatus for fast response and distortion measurement of a signal transfer device. A computer processor generates a multitone test signal of predetermined duration and stores it in a memory. The test signal is read out, converted to analog form, if necessary, and applied to the input of a device under test. The output produced by the device under test in response to the test signal is acquired and digitized, if necessary, and a Fast Fourier Transform is performed on the acquired data to determine its spectral characteristics. Frequency response, harmonic distortion, intermodulation distortion, phase distortion, wow and flutter and other signal transfer characteristics are measured by the CPU by analysis of the output signal.

Abstract: Arcing in an AC power system is detected by monitoring the power waveform for wideband high-frequency noise, and examining the detected noise for patterns of variation in its amplitude synchronized to the power waveform. A narrowband, swept-frequency detector and synchronous averaging may be employed to improve discrimination of arc noise from background interference. An arcing fault interrupter for controlling a single circuit, and a whole house monitor, for detecting arcing anywhere in a house, are described.

Abstract: A testing apparatus for detecting popcorn noise in magnetic heads comprises a fully integrated testing system which includes an analog circuit portion and a digital circuit portion. The analog circuit portion is implemented to interface with a magnetic head while the digital circuit portion is designed to store the testing sequence, analyze the testing data, control and execute the testing routines. The testing apparatus is designed for production environments where testing data are required instantaneously as feedback for production process monitoring.

Abstract: A method and apparatus for generating noise to be used in evaluation and testing of digital or analog integrated circuits. One or more noise generators fabricated on a substrate generate noise representative of the digital switching noise generated by a digital integrated circuit. The noise generator may be programmable to generate noise over a wide frequency and amplitude range. In addition, a plurality of noise generators may be used to independently and simultaneously generate noise signals with multiple frequencies and amplitudes. A test circuit, either analog or digital, is fabricated on the same substrate. The generated noise signal(s) are generated for use in the evaluation and testing of the effects of the noise on the analog or digital test circuit.

Abstract: A method and device for measuring the switching noise of an audio amplifier by measuring the energy of the noise signal at the output of the audio amplifier as the amplifier is switched from one operating condition to another by a control signal, and after first weighing the energy according to the frequency and volume sensitivity of the human ear. The device comprises a control signal generator; an audio band filter connected to the output of the audio amplifier; a meter for measuring the power of the filtered signal; and an integrating element for calculating the energy of the filtered signal.

Abstract: A noise measurement test system 10' for making phase noise and amplitude noise measurements of microwave signals derived from a continuous wave RF source. The system 10' comprises an RF input for receiving an applied RF noise signal and an RF coupler 11 coupled to the RF input for splitting the applied RF noise signal into first and second paths 18a, 18b. A mixer 15 that comprises a synchronous phase detector 15 is coupled to receive signals from the first and second paths 18a, 18b, respectively, and which outputs demodulated phase noise. The first path 18a comprises a variable attenuator 14 and a variable phase shifter 13 coupled between the coupler 11 and the first input of the mixer 15 for providing a reference signal input to the synchronous detector 15. The second path 18b comprises a delay line and an adjustable RF carrier nulling circuit 30 coupled between the coupler 11 and the mixer 15.

Abstract: Surface potential is detected with high precision by removing induction noise generated by a drive circuit and transmitted to a detection electrode. Induction noise imparted by a drive circuit to an A.C. voltage signal is cancelled out by supplying an output of a pre-amplifier for amplifying the A.C. voltage signal derived from a detection electrode and an output of the drive circuit for applying a drive signal to a chopper portion to a differential amplifier and differentially amplifying them. Particularly, an attenuator for making a level of the amplified A.C. voltage signal substantially coincident with a level of a signal from the drive circuit and an inverter/amplifier for making phase deviation coincident are provided in an output portion of the pre-amplifier circuit.

Abstract: An RF device (12), such as an amplifier, is tested by applying a digitally-modulated RF stimulus signal, having a known magnitude and phase angle, to the device to cause it to generate a response signal. The response signal of the device is down-converted and digitized prior to establishing its magnitude and phase angle. The magnitude and phase angle of the digitized, down-converted response signal are compared to the magnitude and phase angle, respectively, of the digitally-modulated stimulus signal to yield transfer functions indicative of the operation of the device.

Abstract: A test system having an improved physical layout and electrical design allows the 1/f noise of metal interconnects to be measured at levels close to that of Johnson or thermal noise. A detailed description of examples of operation of the test system provides evidence of the effectiveness of the test system in minimizing system noise to a level significantly lower than Johnson noise. This permits quantitative measurment of the noise contribution attributable to variations in cross-sectional area of connections for various applications and for qualitative prediction of electromigration lifetimes of metal films, particularly aluminum, having different microstructures. The test system includes an enclosure which includes several nested groups of housings including a sample oven within a device under test box which is, in turn, contained within the system enclosure.

Abstract: A noise analyzer apparatus for a video signal produced by an X-ray imaging system corresponding to an image generates, in response to vertical and horizontal sync pulses, a two-level gating signal which is at a predetermined level solely during the times that intensity information contained in the video signal corresponds to pixels in an adjustably positionable window area of the image. A gated noise measuring circuit responsive to intensity information contained in the video signal and to the gating signal forms a signal which is a measure of a noise content solely within the window area of the image. A signal combiner combines the video signal and a signal derived from the gating signal to produce an augmented video signal containing in its intensity information a marker indicating the location of the window area.

Abstract: A multi-channel electromagnetically transparent voltage probe transmission link system or method monitors a plurality of voltage signals at a plurality of test points of a device under test that is subject to a radiation field with at least two intensity levels. The system or method compares the monitored voltage signals at the first intensity level corresponding to the level at which the monitored voltage signals not being affected by the radiation field, and the second intensity level being greater than the first intensity level. The system or methods determines whether or not the device is affected by the radiation field by determining if the monitored voltage signals are affected by the radiation field at the second intensity level.