English
Related papers

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

200 papers

Optical frequency transfer provides the means for high-fidelity frequency transfer across thousands of kilometers. A critical step in the further developing optical frequency transfer is its capability to transfer a high spectral purity…

Instrumentation and Detectors · Physics 2021-02-25 Liang Hu , Xueyang Tian , Long Wang , Guiling Wu , Jianping Chen

Sixth-generation (6G) wireless communication systems, as stated in the European 6G flagship project Hexa-X, are anticipated to feature the integration of intelligence, communication, sensing, positioning, and computation. An important…

Information Theory · Computer Science 2024-02-16 Eyad Shtaiwi , Ahmed Abdelhadi , Husheng Li , Zhu Han , H. Vincent Poor

The remarkable frequency stability of resonant systems in the optical domain (optical cavities and atomic transitions) can be harnessed at frequency scales accessible by electronics using optical frequency division. This capability is…

We propose a scheme that can generate a tunable double optomechanically induced transparency (OMIT) in a hybrid optomechanical cavity system, in which the mechanical resonator of an optomechanical cavity is coupled to an additional…

Quantum Physics · Physics 2019-10-01 Shi-Chao Wu , Li-Guo Qin , Jian Lu , Zhong-Yang Wang

In this paper a DWT based steganography in frequency domain, termed as ATFDWT has been proposed. Here, the cover image is transformed into the time domain signal through DWT, resulting four sub-image components as 'Low resolution',…

Cryptography and Security · Computer Science 2012-12-18 Madhumita Sengupta , J. K. Mandal , N. Ghoshal

This paper presents a gradient-based method for on-the-fly optimization for both per-frame and per-frequency window length of the short-time Fourier transform (STFT), related to previous work in which we developed a differentiable version…

Signal Processing · Electrical Eng. & Systems 2023-08-07 Maxime Leiber , Yosra Marnissi , Axel Barrau , Mohammed El Badaoui

Modulating macroscopic parameters of materials in time offers innovative avenues for manipulating electromagnetic waves. Due to such enticing prospects, the general research subject of time-varying systems is expanding today in different…

Optics · Physics 2024-12-06 M. S. Mirmoosa , T. Setälä , A. Norrman

Point spread function (PSF) engineering of the emitter can code higher spatial frequency information of an image to break diffraction limit but suffer from the complexed optical systems. Here we present a robust strategy to simultaneously…

Optics · Physics 2021-02-23 Chaohao Chen , Baolei Liu , Yongtao Liu , Jiayan Liao , Xuchen Shan , Fan Wang , Dayong Jin

Optical diffraction tomography (ODT) is a three-dimensional (3D) label-free imaging technique. The 3D refractive index distribution of a sample can be reconstructed from multiple two-dimensional optical field images via ODT. Herein, we…

Optics · Physics 2021-02-03 Chansuk Park , Kyeoreh Lee , Yoonseok Baek , Yongkeun Park

Diverse applications in photonics and microwave engineering require a means of measurement of the instantaneous frequency of a signal. A photonic implementation typically applies an interferometer equipped with three or more output ports to…

The Palomar Transient Factory (PTF) is an optical wide-field variability survey carried out using a camera with a 7.8 square degree field of view mounted on the 48-in Oschin Schmidt telescope at Palomar Observatory. One of the key goals of…

The characterization of non-stationary signals requires joint time and frequency information. However, time (t) and frequency (omega) being non-commuting variables there cannot be a joint probability density in the (t,omega) plane and the…

Data Analysis, Statistics and Probability · Physics 2007-05-23 V. I. Man'ko , R. Vilela Mendes

Time-frequency representations (TFRs) of signals, such as the windowed Fourier transform (WFT), wavelet transform (WT) and their synchrosqueezed variants (SWFT, SWT), provide powerful analysis tools. However, there are many important issues…

Numerical Analysis · Mathematics 2014-05-27 Dmytro Iatsenko , Peter V. E. McClintock , Aneta Stefanovska

We present differential phase-contrast optical coherence tomography (DPC-OCT) with two transversally separated probing beams to sense phase gradients in various directions by employing a rotatable Wollaston prism. In combination with a…

Optics · Physics 2011-11-11 Bettina Heise , David Stifter

A recent advance in optical coherence tomography (OCT), termed swept-source OCT, is generalized into a new technique, Fourier-domain OCT. It represents a realization of a full-field OCT system in place of the conventional serial image…

This paper proposes a frequency/time hybrid integral-equation method for the time dependent wave equation in two and three-dimensional spatial domains. Relying on Fourier Transformation in time, the method utilizes a fixed…

Numerical Analysis · Mathematics 2020-04-30 Thomas G. Anderson , Oscar P. Bruno , Mark Lyon

In this article, we develop comprehensive frequency domain methods for estimating and inferring the second-order structure of spatial point processes. The main element here is on utilizing the discrete Fourier transform (DFT) of the point…

Methodology · Statistics 2025-01-24 Junho Yang , Yongtao Guan

This letter is the first part of a three-part tutorial on orthogonal time frequency space (OTFS) modulation, which is a promising candidate waveform for future wireless networks. This letter introduces and compares two popular…

Information Theory · Computer Science 2022-09-13 Zhiqiang Wei , Shuangyang Li , Weijie Yuan , Robert Schober , Giuseppe Caire

Time-frequency Schmidt (TFS) modes of ultrafast quantum states are naturally compatible with high bit-rate integrated quantum communication networks. Thus they offer an attractive alternative for the realization of high dimensional quantum…

The first part of the paper is devoted to diffraction phenomena that can be expressed by fractional Fourier transforms whose orders are real numbers. According to a scalar theory, diffraction acts on the amplitude of the electric field as…

Optics · Physics 2022-03-17 Pierre Pellat-Finet , Éric Fogret