In order to improve the detection accuracy of wavelength, the filtering and curve fitting technologies were applied in the FBG wavelength demodulation system based on tunable F-P filter. These methods could realize the accurate peak-location of output signals of the photo detector. According to the characteristics of noise, the FIR low-pass filter was designed to filter the obtained light power...

The polarization analysis of light is typically carried out using modulation schemes. The light of an unknown polarization state is passed through a set of known modulation optics, and a detector is used to measure the total intensity passing the system. The modulation optics is modified several times, and, with the aid of several such measurements, the unknown polarization state of the light c...

We propose a Riesz transform approach to the demodulation of digital holograms. The Riesz transform is a higher-dimensional extension of the Hilbert transform and is steerable to a desired orientation. Accurate demodulation of the hologram requires a reliable methodology by which quadrature-phase functions (or simply, quadratures) can be constructed. The Riesz transform, by itself, does not yie...

Natural sounds are rich in long-range temporal structure – like the sentences and phonemes of speech – and a good model of such structures should help solve difficult problems in machine-audition. We propose a new representation for the long-range features in sounds in terms of a product modulatory processes, that form a cascade from slow to fast. In order to produce this representation we argu...

Kalman filtering theory is applied to yield an optimal causal demodulator for pulse-amplitude-modulated (PAM) signals in the presence of white Gaussian noise. The discrete-time data (or sampled continuous-time data) are assumed to he either a stationary or nonstationary Gaussian stochastic process, io general nonwhite. Optimal demodulation with delay is also achieved by application of Kalman fi...

Introduction 1 Background 1 Digital Communication Systems 2 Baseband Signal Representation 2 Line Codes 3 Passband Signal Representation 3 Constellation Diagrams 4 Generation of Coherent PSK Signals 4 Representation of BPSK 4 Generation of BPSK 5 Representation and Generation of QPSK 5 M-ary PSK 7 Demodulation of Coherent PSK Signals 8 Spectral Characteristics of PSK Signals 9 Error Performance...