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A recursive approach to signal detection
Likelihood ratio analysis for detecting signals in additive non-white noise
Derivative approximation for recursive signal detection
Recursive signal detection scheme, obtaining SNR by derivative approximation
Stability in signal detection problems.
Stability in signal detection and signal measurement concerning hypotheses test and parameter estimation problems
Evoked potential correlates of auditory signal detection
Human auditory signal detection related to averaged evoked potential in scalp by electrophysiological measurements
Stability in signal detection problems.
Stability in signal detection and measurement based on statistical inference made from values of functional on sample space
Phase-shift-keyed signal detection with noisy reference signals.
Graph and derivation of performance characteristics of phase-shift-keyed communication systems where receiver phase rerference is noisy
Signal detection amid noise with known statistics
Conventional methods of signal detection are based on the comparison of a local signal-to-noise ratio S/N to some threshold value. We present a new method that compares instead the histogram of the data with the one expected for background noise alone. Signals are detected from discrepancies between the two. We expect it to be applicable in the detection of signals from any data whose background statistics is known. To illustrate the method, we apply it to the case of photon-limited imaging data where the underlying background is Poissonian. Numerical simulations are used to check the efficiency of our method, finding that for signals with low S/N (less than 5), it detects signals with a higher degree of reliability than the conventional method.
Signal detection techniques for a discrete- frequency, phase-coherent pulse frequency modulation /PFM/ telemetry signal.
Signal detection techniques for discrete- frequency, phase-coherent pulse frequency modulation telemetry system, using analog and digital circuits
Statistical tests for signal detection
Statistical tests for signal detection and correlation coefficients
Walsh transforms and signal detection
The detection of signals using Walsh power spectral estimates is analyzed. In addition, a generalization of this method of estimation is evaluated. The conclusion is that Walsh transforms are not suitable tools for the detection of weak signals in noise.
Evaluation of a nonlinear method for the enhancement of tonal signal detection
A method is presented for biasing spectral estimates to enhance detection of tonal signals against a background of broadband noise. In this method, a nonlinear average of an ensemble of individual spectral estimates is made where broadband noise energy is biased downward, pure tone energy is unbiased, and a mixture of the two is biased by an amount that depends on the ratio of tonal energy to broadband energy. The method is analyzed to provide estimates of the extent of tonal signal detection enhancement.
Feedback and psychophysical variables in signal detection.
Feedback and psychophysical variables in signal detection
Studies of auditory information processing emphasizing the application of signal detectability theory to the auditory sensory responses Semiannual report, 1 Dec. 1965 - 31 May 1966 and eighth quarterly status report, 1 Mar. - 31 May 1966
Free response to auditory signal detection, signal fading rate on energy band detector for electric ear model, and brightness adaptation research projects
The effects of pulse rate, power, width and coding on signal detectability
The effects on the signal detectability of varying the pulse repetition rate (PRF), peak pulse power (p(pk)) and pulse width (tau(p)) (tp) are examined. Both coded and uncoded pulses are considered. The following quantities are assumed to be constant; (1) antenna area, (z)echo reflectivity, (3) Doppler shift, (4) spectral width, (5) spectral resolution, (6) effective sampling rate, and (7) total incoherent spectral averagaing time. The detectability is computed for two types of targets.
System and Method for Multi-Wavelength Optical Signal Detection
The system and method for multi-wavelength optical signal detection enables the detection of optical signal levels significantly below those processed at the discrete circuit level by the use of mixed-signal processing methods implemented with integrated circuit technologies. The present invention is configured to detect and process small signals, which enables the reduction of the optical power required to stimulate detection networks, and lowers the required laser power to make specific measurements. The present invention provides an adaptation of active pixel networks combined with mixed-signal processing methods to provide an integer representation of the received signal as an output. The present invention also provides multi-wavelength laser detection circuits for use in various systems, such as a differential absorption light detection and ranging system.
Fiber optic rotation sensor /FORS/ signal detection and processing
The recent development of low-loss single-mode optical fiber waveguides for light has made possible a new class of inertial reference devices built on the principle of a closed loop interferometer. Light circulating through the loop in both directions experiences a relative phase delay proportional to rotation rate about the loop axis. This paper derives the phase delay and discusses signal detection, signal processing techniques and error sources. It is concluded that synchronous modulation and demodulation and an active gain control at the signal calculation level are required to eliminate drift errors. Potential performance is extraordinarily good; rotation rate sensitivity of a few milli-arc seconds per second and angular position random walk errors of an arc second per square root hour appear feasible.
Derivative approximation for recursive signal detection
Derivative approximation techniques for recursive signal detection, using computer program for solving optimum and suboptimum processes signal to noise ratio in effectiveness evaluation