Abstract: Transmitter noise cancellation may be applied on a channel by channel basis to active channels of an incoming radio frequency signal received at a receiver. A noise cancellation filter may be provided for each active channel in a predetermined signal band. Applying noise cancellation on a per active channel basis instead of to the entire receive band may substantially reduce the filtering requirement and number of filter coefficients or taps to save power and reduce manufacturing costs. Channelized transmitter noise cancellers, multi transmitter-receiver cross coupling cancellers, and hybrid full signal band and channelized transmitter noise cancellers are also provided.

Abstract: Disclosed are a device and a method for comparing a detected frequency signal (first frequency signal) and a second frequency signal which is obtained by delaying the detected frequency, to determine whether the frequency transitioned to a predetermined area on high frequency side or reached a predetermined value on the upward direction side. The frequency detection device (1) comprises: a delayed signal output circuit (11) that outputs a second frequency signal (F2) obtained by delaying the first frequency signal (F1), which has a frequency that changes over time, by a set period (?i); and a determination circuit (12), which inputs the first frequency signal (F1) and the second frequency signal (F2), determines whether or not the cycle of the first frequency signal (F1) is included in the cycle of the second frequency signal (F2) and/or whether or not the cycle of the second frequency signal (F2) is included in the cycle of the first frequency signal (F1), and outputs a determination signal.

Abstract: The present disclosure describes a novel method and apparatus for using a device's power and ground terminals as a test and/or debug interface for the device. According to the present disclosure, messages are modulated over DC voltages applied to the power terminals of a device to input test/debug messages to the device and output test/debug messages from the device. The present disclosure advantageously allows a device to be tested and/or debugged without the device having any shared or dedicated test or debug interface terminals.

Abstract: A method of detecting a failure of an alternator supplying three-phase electricity to a load, the method comprising the steps of determining a duty ratio for each of the phases at the output of the alternator, determining phase differences between the phases at the output of the alternator; and determining the presence of a failure as a function of the phase differences and as a function of a comparison of the duty ratios. A power supply device is also provided for implementing the method.

Abstract: A personal alerting device and method for detecting an approaching sound source includes a sound detector for detecting environmental sounds and for providing an electrical signal to a sound analyzer. The sound signal is analyzed to determine a baseline sound pattern comprising a plurality of distinct sounds corresponding to sounds emitted from a reference sound source. The distinct sounds in the baseline sound pattern may have substantially the same amplitude and time interval. The sound signal is monitored and compared against the baseline sound pattern to determine whether a target sound pattern is present in the sound signal, the target sound pattern corresponding to sounds emitted by the approaching sound source. When it is determined that the target sound is present in the sound signal, one or more of an audible, visual and tactile alert may be emitted to provide warning of the approaching sound source.

Abstract: An apparatus for determining a resonant frequency of a wind turbine tower is provided. The apparatus includes a processing unit configured to receive an acceleration measurement value, the acceleration measurement value representative of the acceleration of the wind turbine tower in the direction parallel to a rotor rotational axis of the wind turbine and/or in the direction perpendicular to both the rotor rotational axis and the tower axis of the wind turbine. The apparatus includes a memory configured to store a series of acceleration measurement values, and the processing unit includes a Fourier transform module configured to calculate a spectral vector based on calculating a convolution-based fast Fourier transform of the series of acceleration measurement values, and includes a resonant frequency calculation module configured to calculate the tower resonant frequency based on the calculated spectral vector.

Abstract: There is provided a filter characteristic adjusting apparatus and a filter characteristic adjusting method which can avoid an increase in circuit scale of the filter characteristic adjusting apparatus, and can speedily adjust a characteristic frequency of the filter to a desired frequency. When performing characteristic adjustment for the filter, the test signal generation unit (31) generates a test signal (s14) which is a pulse signal having the same frequency as the characteristic frequency of the filter (10) on the basis of a reference signal (s17), and a phase-shifted test signal (s14?) that is obtained by shifting the phase of the test signal (s14) by a predetermined amount with a phase shift unit (32) in a control signal generation unit (33) is compared with a filter output signal (s16) that is obtained by inputting the test signal (s14) into the filter (10) to obtain a phase difference between the signals, and then the phase difference is subjected to a binary search to generate a control signal (s11).

Abstract: Signal-integrity measurement systems and methods utilizing unique time-base generation techniques for controlling the sampling of one or more signals under test. A time-base generator made in accordance with the present disclosure includes a phase filter and modulation circuitry that generates a rapidly varying phase signal as a function of the output of a sigma-delta modulator. The phase filter filters unwanted high-frequency phase components from the rapidly varying phase signal. The filtered signal is used to clock one or more samplers so as to create sampling instances of the signal(s) under test. The sampling instances are then analyze using any one or more of a variety of techniques suited to the type of signal(s) under test.

Abstract: A method for measuring the damping factor of an Nth-order phase-locked loop, wherein N>1, and a system, apparatus, and program that operate in accordance with the method. The method includes applying a modulation source at an input to the phase-locked loop. The method also includes measuring the output response to various levels of frequency modulation, measuring the ?3 dB cutoff frequency of the phase-locked loop, and measuring the peak frequency of the phase-locked loop. The method further includes calculating the damping factor of the phase-locked loop as a function of the ?3 dB cutoff frequency and the peak frequency.

Abstract: An acquisition apparatus for a test and measurement instrument includes an input to receive an input signal, a digitizer to digitize a selected signal, a bypass path to selectively couple the input to the digitizer, a frequency shift path to frequency shift the input signal and selectively couple the frequency-shifted input signal to the digitizer, the frequency shift path including a means for frequency shifting, an input switch to switch the input signal to one of the bypass path and the frequency shift path, and an output switch to provide the selected signal to the digitizer by selectively coupling an output of one of the frequency shift path and the bypass path to the digitizer.

Abstract: A processor that utilizes the presence of harmonic components in a noisy signal environment to enhance the desired frequency spectrum of the signal. Received signal and noise are filtered to separate the harmonic components of the signal. These harmonic components are then combined in a prescribed manner to form a multiplicity of combined signals with varying harmonic content. The combined signals are then further processed to establish a signal detection.

Abstract: A test configuration and a method for testing a digital electronic filter, include feeding back an output of the filter to an input in such a manner that a digital output signal from the filter is applied to the input as a test signal. The test signal is applied to the filter and a response signal is fed back to the input as the next test signal.

Abstract: A method is provided to process system test data to determine certification parameters of the system based on the test data. For a torpedo launch system, the velocity data is generated by a Pressure/Velocity/Displacement housing interfaced with a computer based data acquisition system and known launch system and test parameters, such as sample rate, muzzle exit length, time of acquisition, decimation factor and low pass cutoff frequency are provided as inputs. The method forces assigns a value of zero to any data less than a predetermined threshold in order to eliminate non-zero levels contributed by ambient noise. The method then passes the data through a filter chosen to agree with hand fit smoothing methods, so as to obtain a smoothed velocity profile. The smoothed data is processed to obtain and display an acceleration profile and a displacement profile, as well as data points for peak acceleration, time at peak, acceleration pulse width, muzzle exit velocity and time at exit.

Abstract: An active filter device provided for compensating harmonic distortion in a supply line by injecting for each harmonic (fk) to be considered a compensation current. The compensation current being determined by injecting a monitoring current on the supply line at a first (f1) and second (f2) frequency value, offset respectively on either side of the considered harmonic, and measuring response currents generated by the supply line upon injection of said monitoring currents.