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Phase compensation technique for signals received at widely spaced antennas and processed at central location
Optical detector using length of single mode optical waveguide with photodetector at output for null detection
Appleton-Hartree equations for propagation of electromagnetic waves collisionless magnetoionic medium to determine effect of electron density on laser behavior
Producing optical excitations by low energy ion atom and ion molecule collisions
Phase error probability distribution in communication systems where bandpass limiters precede RF carrier tracking loop
Error probabilities for binary DPSK communication through frequency selective channels with predetection diversity matched filter reception
Refractive effects in gaseous infrared Q switched lasers
Tracking oscillator consists of modified phase-lock loop which controls voltage-controlled oscillator capable of automatic lock-on and track of periodic input waveform over frequency ratio 500-1. It is used in telemetry and communications systems where large signal fluctuations are encountered.
Microwave impedance measurements for determining space charge waves in semiconductors
Mariners 6 and 7 range and Doppler tracking data for studying Martian mass and earth-moon mass ratio
Maximum likelihood receiver /MLR/ to detect pulsed signal propagated through turbulent medium, assuming optical propagation over long path in atmosphere
Lens rotation technique of noise diffraction pattern elimination spreads diffracted energy, normally concentrated over small area of image, over much larger annular area. Technique advantages include simplified lens selecting process, reduced clean room requirements, and low cost equipment requirements.
Laser frequencies may be reduced to single frequency or selected frequencies. For single frequency performance, spacing of frequencies falls in natural line width. For two or more frequencies, thicker spacing is used. Configuration adapts to operation with Kerr or Pockel cell for Q switching.
Digitized optical detectors for cloud data processing onboard satellite using Fourier analysis
A technique is described and analyzed for using the single beam laser receiver to measure the wave structure function of atmospheric turbulence. The measurement procedure is as follows: first, the telescope aperture is masked with an opaque screen having two small holes; one hole is covered and the output of the laser receiver is measured; finally, the output of the laser receiver is measured with both holes uncovered. By repeating these measurements for different hole separations, the wave structure function can be derermined.
It is shown that an automatic imaging system consisting of a combination of optical and digital computer elements is feasible and has considerable advantages over direct image scanning systems. With such a system, it is possible to process very large quantities of remotely sensed image spectra.