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Related papers: Randomness and metastability in CDMA paradigms

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This article introduces a novel communication paradigm for the unsourced, uncoordinated Gaussian multiple access problem. The major components of the envisioned framework are as follows. The encoded bits of every message are partitioned…

Information Theory · Computer Science 2020-11-23 Asit Pradhan , Vamsi Amalladinne , Avinash Vem , Krishna R. Narayanan , Jean-Francois Chamberland

We consider binary continuous phase modulation (CPM) signals used in some recent low-cost and low-power consumption telecommunications standard. When these signals are generated through a low-cost transmitter, the real modulation index can…

Information Theory · Computer Science 2015-09-14 Malek Messai , Colavolpe Giulio , Amis Karine , Guilloud Frederic

Signal decomposition and multiscale signal analysis provide many useful tools for time-frequency analysis. We proposed a random feature method for analyzing time-series data by constructing a sparse approximation to the spectrogram. The…

Signal Processing · Electrical Eng. & Systems 2023-03-17 Nicholas Richardson , Hayden Schaeffer , Giang Tran

We establish a link between metastability and a discrete time-crystalline phase in a periodically driven open quantum system. The mechanism we highlight requires neither the system to display any microscopic symmetry nor the presence of…

Statistical Mechanics · Physics 2019-01-10 F. M. Gambetta , F. Carollo , M. Marcuzzi , J. P. Garrahan , I. Lesanovsky

Recently, a new class of binary codes for overloaded CDMA systems are proposed that not only has the ability of errorless communication but also suitable for detecting active users. These codes are called COWDA [1]. In [1], a Maximum…

Information Theory · Computer Science 2010-01-26 Ali Mousavi , Pedram Pad , Farokh Marvasti

The direct-sequence code-division multiple access (DS-CDMA) cellular downlink is modeled by a constrained random spatial model involving a fixed number of base stations placed over a finite area with a minimum separation. The analysis is…

Information Theory · Computer Science 2012-10-16 Matthew C. Valenti , Don Torrieri , Salvatore Talarico

Sparse code multiple access (SCMA) is a promising multiuser communication technique for the enabling of future massive machine-type networks. Unlike existing codebook design schemes assuming uniform power allocation, we present a novel…

Information Theory · Computer Science 2021-10-11 Xudong Li , Zhicheng Gao , Yiming Gui , Zilong Liu , Pei Xiao , Lisu Yu

We consider the problem of metastability in a probabilistic cellular automaton (PCA) with a parallel updating rule which is reversible with respect to a Gibbs measure. The dynamical rules contain two parameters $\beta$ and $h$ which…

Statistical Mechanics · Physics 2009-10-31 Stephen Bigelis , Emilio N. M. Cirillo , Joel L. Lebowitz , Eugene R. Speer

We study random perturbations of multidimensional piecewise expanding maps. We characterize absolutely continuous stationary measures (acsm) of randomly perturbed dynamical systems in terms of pseudo-orbits linking the ergodic components of…

Dynamical Systems · Mathematics 2014-01-30 Wael Bahsoun , Huyi Hu , Sandro Vaienti

Kudekar et al. proved that the belief-propagation (BP) performance for low-density parity check (LDPC) codes can be boosted up to the maximum-a-posteriori (MAP) performance by spatial coupling. In this paper, spatial coupling is applied to…

Information Theory · Computer Science 2016-11-18 Keigo Takeuchi , Toshiyuki Tanaka , Tsutomu Kawabata

We demonstrate the advantages of randomization in coherent quantum dynamical control. For systems which are either time-varying or require decoupling cycles involving a large number of operations, we find that simple randomized protocols…

Quantum Physics · Physics 2009-11-13 Lea F. Santos , Lorenza Viola

This paper presents a statistical framework for assessing wireless systems performance using hierarchical data mining techniques. We consider WCDMA (wideband code division multiple access) systems with two-branch STTD (space time transmit…

Computational Engineering, Finance, and Science · Computer Science 2007-05-23 Alex Verstak , Naren Ramakrishnan , Kyung Kyoon Bae , William H. Tranter , Layne T. Watson , Jian He , Clifford A. Shaffer , Theodore S. Rappaport

Dynamic metasurface antennas (DMA) provide low-power beamforming through reconfigurable radiative slots. Each slot has a tunable component that consumes low power compared to typical analog components like phase shifters. This makes DMAs a…

Signal Processing · Electrical Eng. & Systems 2025-10-10 Joseph M. Carlson , Nitish V. Deshpande , Miguel Rodrigo Castellanos , Robert W. Heath

Sparse code multiple access (SCMA) is a promising technique for enabling massive connectivity and high spectrum efficiency in future machine-type communication networks. However, its performance crucially depends on well-designed…

Information Theory · Computer Science 2024-04-05 Tuofeng Lei , Qu Luo , Shuyan Ni , Shimiao Chen , Xin Song , Pei Xiao

We quantitatively characterize the metastability in a multi-phase lattice Boltzmann model. The structure factor of density fluctuations is theoretically obtained and numerically verified to a high precision, for all simulated wave-vectors…

Statistical Mechanics · Physics 2022-12-20 Matteo Lulli , Luca Biferale , Giacomo Falcucci , Mauro Sbragaglia , Dong Yang , Xiaowen Shan

In this paper, we present an efficient algorithm to sample random sparse matrices to be used as check matrices for quantum Low-Density Parity-Check (LDPC) codes. To ease the treatment, we mainly describe our algorithm as a technique to…

Information Theory · Computer Science 2026-01-27 Paolo Santini

This paper considers a general framework for massive random access based on sparse superposition coding. We provide guidelines for the code design and propose the use of constant-weight codes in combination with a dictionary design based on…

Information Theory · Computer Science 2022-07-27 Patrick Agostini , Zoran Utkovski , Alexis Decurninge , Maxime Guillaud , Slawomir Stanczak

The problem of uplink transmissions in massive connectivity is commonly dealt with using schemes for grant-free random access. When a large number of devices transmit almost synchronously, the receiver may not be able to resolve the…

Signal Processing · Electrical Eng. & Systems 2024-12-09 Ao Chen , Wei Chen , Bo Ai , Petar Popovski

This paper studies a large random matrix system (LRMS) model involving an arbitrary signal distribution and forward error control (FEC) coding. We establish an area property based on the approximate message passing (AMP) algorithm. Under…

Information Theory · Computer Science 2021-06-07 Lei Liu , Chulong Liang , Junjie Ma , Li Ping

We introduce the concept of stationary metastable states (SMS's) in the presence of another more stable state. The stationary nature allows us to study SMS's by using a restricted partition function formalism as advocated by Penrose and…

Statistical Mechanics · Physics 2007-05-23 P. D. Gujrati