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Related papers: Optical Phase-Space-Time-Frequency Tomography

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To quantify the effect of decoherence in quantum measurements, it is desirable to measure not merely the square modulus of the spatial wavefunction, but the entire density matrix, whose phases carry information about momentum and how pure…

Quantum Physics · Physics 2009-10-30 Max Tegmark

The optical wireless communication (OWC) with the intensity modulation (IM), requires the modulated radio frequency (RF) signal to be real and non-negative. To satisfy the requirements, this paper proposes two types of mixed orthogonal…

Signal Processing · Electrical Eng. & Systems 2020-11-19 Xu Li , Jingjing Huang , Yibo Lyu , Rui Ni , Jiajin Luo , Junping Zhang

In this paper we introduce a new 2D modulation technique called OTFS (Orthogonal Time Frequency & Space) that transforms information carried in the Delay-Doppler coordinate system to the familiar time-frequency domain utilized by…

Information Theory · Computer Science 2016-08-11 Anton Monk , Ronny Hadani , Michail Tsatsanis , Shlomo Rakib

We present a simple, frequency domain, preprocessing step to Kirchhoff migration that allows the method to image scatterers when the wave field phase information is lost at the receivers, and only intensities are measured. The resulting…

Numerical Analysis · Mathematics 2016-09-21 Patrick Bardsley , Fernando Guevara Vasquez

Entanglement is a key resource in quantum technologies, enhancing precision and resolution in imaging and sensing by leveraging the cross-correlation of photon pairs. This correlation enables precise time synchronization of photons reaching…

Optoacoustic image formation is conventionally based upon ultrasound time-of-flight readings from multiple detection positions. Herein, we exploit acoustic scattering to physically encode the position of optical absorbers in the acquired…

Biological Physics · Physics 2019-10-30 Xose Luis Dean-Ben , Ali Ozbek , Hernan Lopez-Schier , Daniel Razansky

Orthogonal time-frequency space (OTFS) is a potential waveform for integrated sensing and communications (ISAC) systems because it can manage communication and sensing metrics in one unified domain, and has better performance in high…

Signal Processing · Electrical Eng. & Systems 2025-04-08 Zhenyu Zhang , Qianli Wang , Gang Liu , FeiFei Gao , Pingzhi Fan

We propose a method for constructing the time-dependent phase space distribution function (DF) of a collisionless system from an isolated kinematic snapshot. In general, the problem of mapping a single snapshot to a time-dependent function…

Astrophysics of Galaxies · Physics 2021-07-21 Keir Darling , Lawrence M. Widrow

This paper introduces a new two-dimensional modulation technique called Orthogonal Time Frequency Space (OTFS) modulation. OTFS has the novel and important feature of being designed in the delay-Doppler domain. When coupled with a suitable…

The fast Fourier transform, FFT, is a useful and prevalent algorithm in signal processing. It characterizes the spectral components of a signal, or is used in combination with other operations to perform more complex computations such as…

Signal Processing · Electrical Eng. & Systems 2017-11-08 Hani Nejadriahi , David HillerKuss , Jonathan K. George , Volker J. Sorger

Long-distance quantum communication relies on storing and retrieving photonic qubits in orthogonal field modes. The available degrees of freedom for photons are polarization, spatial-mode profile, and temporal/spectral profile. To date,…

Quantum Physics · Physics 2015-06-18 Dileep V. Reddy , Michael G. Raymer , Colin J. McKinstrie

There is an increasing need for label free methods that could reveal intracellular structures and dynamics. In this context, we develop a new optical tomography method working in transmission - Full-field optical transmission tomography…

Optical coherence tomography (OCT) is a powerful technology for rapid volumetric imaging in biomedicine. The bright field imaging approach of conventional OCT systems is based on the detection of directly backscattered light, thereby…

A cascaded iterative Fourier transform (CIFT) algorithm is presented for optical security applications. Two phase-masks are designed and located in the input and the Fourier domains of a 4-f correlator respectively, in order to implement…

Optics · Physics 2009-11-10 Guohai Situ , Jingjuan Zhang

The second part of the article is devoted to field transfers by diffraction that are represented by fractional Fourier transformations whose orders are complex numbers. The corresponding effects on the Wigner distributions associated with…

Optics · Physics 2022-03-29 Pierre Pellat-Finet , Éric Fogret

Traditional full-field optical coherence tomography (FF-OCT) is effective for rapid cross-sectional imaging but often suffers from incoherent signals due to imbalanced light intensities between the sample and reference arms. While the…

Optics · Physics 2024-10-17 Youlong Fan , Qingye Hu , Zhongping Wang , Zengming Zhang , Xiantao Wei

We introduce and experimentally implement Fourier-plane phase synchronization for optical microscopy, and demonstrate its performance with interferometric scattering microscopy. By combining a photothermal phase plate and laser beam…

This work proposes a new precoded filter bank (FB) system via a two-dimensional (2D) fast Fourier transform (2D-FFT). Its structure is similar to Orthogonal Time Frequency Space (OTFS) systems, where the OFDM transmitter is changed to a…

Information Theory · Computer Science 2022-06-14 R. Pereira Junior , C. A. F. da Rocha , B. S. Chang , D. Le Ruyet

A time-of-flight (ToF) imaging system is proposed and its working principle demonstrated. To realize this system, a new device, a free-space optical mixer, is designed and fabricated. A scene is illuminated (flashed) with a megahertz level…

Metaplectic Wigner distributions generalize the most popular time-frequency representations, such as the short-time Fourier transform (STFT) and $\tau$-Wigner distributions, using metaplectic operators. However, in order for a metaplectic…

Analysis of PDEs · Mathematics 2024-03-27 Elena Cordero , Gianluca Giacchi