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Optical heterodyne (coherent) detection
American Journal of Physics, 1988The optical heterodyne principle is described and its history traced. Early hopes for optical communication by this technique were frustrated by problems of wavefront degradation and laser frequency instability. However, fiber optics has recently revitalized this as an attractive possibility. In the interim, many other successful applications have been
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Fast stereovision by coherence detection
1997A new approach to stereo vision based on similarities between optical flow estimation and disparity computation is introduced. The fully parallel algorithm utilizes fast filter operations and aliasing effects of simple disparity detectors within a coherence detection scheme.
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Algorithms for Coherent Detection
Optical Fiber Communication Conference, 2010□ Fiber optics is converging with other digital communications fields – cellular, satellite, digital subscriber line, etc. □ But techniques from existing fields are of limited help ▪ our carrier linewidth is much higher, 10-4 baud rate ▪ our impairments are of long duration, >100 symbols ▪ our data rate is much higher, 100Gb/s □ We must develop our own
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Optically detected spin coherence of single molecules
Physical Review Letters, 1993no ...
Wrachtrup, J. +4 more
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Coherent Detection: Born again?
2006 IEEE LEOS Annual Meeting Conference Proceedings, 2006This paper describes a coherent optical receiver, which can cope with multi-level modulation formats. The carrier-phase drift is estimated with digital signal processing on the homodyne-detected signal, entirely restoring the complex amplitude of the signal.
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Detection efficiency of coherent optical radar
Applied Optics, 1984Using the Huygens-Fresnel principle, the detection efficiency of a coherent optical radar is formulated. This formulation includes the effect of misalignment between the signal field and the local oscillator field. In the far-field case, the detection efficiency of a diffuse target is approximately half that of a glint target when the transmitter and ...
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Generalized non-coherent detection.
2009The objective of this thesis is to introduce new power efficient non-coherent receiver structures for linear (Quadrature Amplitude Modulated and Phase Shift Keyed) as well as Continuous Phase Modulated signals. A generalized non-coherent detection theory, addressing single or multi-amplitude/phase signals as well as operation in time dispersive ...
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Detecting coherent and incoherent frequency modulation
Hearing Research, 2000Three experiments investigated whether or not the auditory system contains a neural mechanism that is sensitive to differences in the pattern of frequency modulation imposed on widely separated carriers. Experiment 1 measured the discrimination between an unmodulated two-tone complex and one in which either coherent or incoherent frequency modulation ...
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Coherent or Heterodyne Detection
1978In the previous chapter we discussed the detection of the incident power in an optical or infrared wave, basically ignoring the actual frequency of the wave except in the value of the quantum energy and the wavelength or frequency cutoff of the photon detector.
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Coherent Detection of DQPSK for Tolerance to Coherent Crosstalk
Coherent Optical Technologies and Applications, 2008Coherent crosstalk is a significant challenge in OCDM/A systems especially for high spectral efficiency coherent implementations. We study its impact on DQPSK with coherent detection. An improvement in performance is seen over direct detection.
A. Agarwal +5 more
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