Interference (wave propagation)

About: Interference (wave propagation) is a research topic. Over the lifetime, 26086 publications have been published within this topic receiving 321110 citations.

Adaptive Radar Beamforming for Interference Mitigation in Radar-Wireless Spectrum Sharing

Abstract: The key to the feasibility of spectrum sharing between radar and wireless systems is effective mainlobe interference mitigation processing by the radar. Traditional array processing is capable to cancel sidelobe interferences only. This letter presents an innovative beamforming approach, the first of its kind, to eliminate wireless interference in both mainlobe and sidelobe directions based on a coherent phase-coding multiple-input multiple-output (MIMO) radar platform. The theoretical proof and conditions of simultaneous mainlobe interference cancellation and target detection using coherent MIMO radar are mathematically derived and numerically verified. The simulation results demonstrate the radar can effectively eliminate wireless interferences from base stations and mobile handsets during spectrum-sharing.

System and method for holographic imaging with discernible image of an object

Abstract: A system and method for three-dimensional imaging utilize a lens to perform a two-dimensional Fourier transform of an interference pattern while focusing the pattern on a two-dimensional detector array which is positioned in the image plane of the lens. This allows immediate previewing of the imaged object for proper positioning. Coherent energy beams are utilized to create a series of interference patterns, or image-plane holograms, each at a different frequency of the source energy beams. Furthermore, at each frequency, the relative phase between an object and a reference energy beam is varied to capture the complex values associated with the interference patterns. After capturing and storing the various interference patterns, a computer performs a one-dimensional Fourier transform, or other simplified processing to generate the three-dimensional image of the object. The image resolution extends to the micron range making this system and method easily adaptable to a variety of three-dimensional inspection applications.

Interference rejection combining for GSM

Abstract: Digital cellular communication systems in urban areas are today beginning to be limited in performance by interference. To further increase the capacity in these areas, more advanced detection schemes could be used. We study how the performance of the MLSE equalizer can be improved by utilizing interference suppression. Simulation results for a GSM system under realistic conditions are presented.

Dynamic channel assignment

Abstract: This invention provides interference predictions, suitable for least interference dynamic channel assignment use or other frequency hopping uses by de-coupling the time slot assignment and the frequency hopping pattern assignment. In particular, a least interfered time slot is selected based on an aggregate interference measurement performed across an entire transmission band or a pre-specified range of frequencies in the transmission band. A user is assigned a least interfered time slot and provided an appropriate frequency hopping pattern.

Observations of dust acoustic waves driven at high frequencies: Finite dust temperature effects and wave interference

Abstract: An experiment has been performed to study the behavior of dust acoustic waves driven at high frequencies (f>100Hz), extending the range of previous work. In this study, two previously unreported phenomena are observed—interference effects between naturally excited dust acoustic waves and driven dust acoustic waves, and the observation of finite dust temperature effects on the dispersion relation.