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Related papers: Asynchronous CDMA Systems with Random Spreading-Pa…

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In this work, we analyze the performance of a signature quantization scheme for reverse-link Direct Sequence (DS)- Code Division Multiple Access (CDMA). Assuming perfect estimates of the channel and interference covariance, the receiver…

Information Theory · Computer Science 2011-02-18 Wiroonsak Santipach

A constant K-user interference channel in which the users are not symbol-synchronous is considered. It is shown that the asynchronism among the users facilitates aligning interfering signals at each receiver node while it does not affect…

Information Theory · Computer Science 2015-03-17 Mehdi Torbatian , Hossein Najafi , Mohamed Oussama Damen

A $K$-user pseudo-orthogonal (PO) randomly spread CDMA system, equivalent to transmission over a subset of $K'\leq K$ single-user Gaussian channels, is introduced. The high signal-to-noise ratio performance of the PO-CDMA is analyzed by…

Information Theory · Computer Science 2007-07-13 Ori Shental , Ido Kanter

Spectrum sensing is essential in cognitive radio to enable dynamic spectrum access. In many scenarios, primary user signal must be detected reliably in low signal-to-noise ratio (SNR) regime under required sensing time. We propose to use…

Information Theory · Computer Science 2009-06-04 Kun Zheng , Husheng Li , Seddik M. Djouadi , Jun Wang

In this paper, the effects of interference on composite fading environments, where multipath fading coexists with shadowing, are investigated. Based on some mathematical convenient expressions for the sum of squared…

Information Theory · Computer Science 2014-06-17 Petros S. Bithas , Athanasios A. Rontogiannis

Multiple transmitting antennas can considerably increase the downlink spectral efficiency by beamforming to multiple users at the same time. However, multiuser beamforming requires channel state information (CSI) at the transmitter, which…

Information Theory · Computer Science 2017-01-31 Xu Du , John Tadrous , Ashutosh Sabharwal

We have proposed a quasi-large random-sequence (QLRS) CDMA where K users access a point through a common channel with spectral spreading factor N. Each bit is extended by a temporal spreading factor B and hopped on a BN-chip random sequence…

Information Theory · Computer Science 2008-02-26 Yi Sun

Millimeter wave MIMO combines the benefits of compact antenna arrays with a large number of elements and massive bandwidths, so that fully digital beamforming has the potential of supporting a large number of simultaneous users with {\it…

Signal Processing · Electrical Eng. & Systems 2020-07-02 Mohammed Abdelghany , Ali A. Farid , Upamanyu Madhow , Mark J. W. Rodwell

The main objective of this paper is to compare block transmission system performance analytically for Code Divisional Multiple Access (CDMA) modulations in Generalized Multicarrier environment against linear modulation techniques for both…

Information Theory · Computer Science 2013-06-03 Anwarul Azim

This paper provides the signal-to-interference-plus-noise ratio (SINR) complimentary cumulative distribution function (CCDF) and average data rate of the normalized SNR-based scheduling in an uplink cellular network using stochastic…

Information Theory · Computer Science 2018-02-08 Shotaro Kamiya , Koji Yamamoto , Seong-Lyun Kim , Takayuki Nishio , Masahiro Morikura

Dynamic spectrum access (DSA) benefits from detection and classification of interference sources including in-network users, out-network users, and jammers that may all coexist in a wireless network. We present a deep learning based signal…

Networking and Internet Architecture · Computer Science 2019-09-27 Yi Shi , Kemal Davaslioglu , Yalin E. Sagduyu , William C. Headley , Michael Fowler , Gilbert Green

In the context of communication-centric integrated sensing and communication (ISAC), the orthogonal frequency division multiplexing (OFDM) waveform was proven to be optimal in minimizing ranging sidelobes when random signaling is used. A…

Signal Processing · Electrical Eng. & Systems 2025-05-06 Karim A. Said , Ibraheem Alturki , Husheng Li , Elizabeth Bentley , Lingjia Liu

Asynchronous random access (RA) protocols are particularly attractive for their simplicity and avoidance of tight synchronization requirements. Recent enhancements have shown that the use of successive interference cancellation (SIC) can…

Information Theory · Computer Science 2016-07-22 Federico Clazzer , Francisco Lazaro , Gianluigi Liva , Mario Marchese

In this paper we introduce a new class of codes for over-loaded synchronous wireless and optical CDMA systems which increases the number of users for fixed number of chips without introducing any errors. Equivalently, the chip rate can be…

Information Theory · Computer Science 2008-10-18 P. Pad , F. Marvasti , K. Alishahi , S. Akbari

This paper studies joint spectrum allocation and user association in large heterogeneous cellular networks. The objective is to maximize some network utility function based on given traffic statistics collected over a slow timescale,…

Information Theory · Computer Science 2018-10-17 Binnan Zhuang , Dongning Guo , Ermin Wei , Michael L. Honig

The joint design of analog beamforming and power allocation is investigated for a single radio-frequency chain multiuser time-division multiple access system under a max-min signal-to-noise ratio (SNR) criterion. A hardware-efficient…

Signal Processing · Electrical Eng. & Systems 2026-04-14 Songnan Gu , Chongjun Ouyang , Hao Jiang , Xingqi Zhang

The fundamental diversity-multiplexing tradeoff (DMT) of the quasi-static fading, symmetric $2$-user MIMO interference channel (IC) with channel state information at the transmitters (CSIT) and a short term average power constraint is…

Information Theory · Computer Science 2010-06-08 Sanjay Karmakar , Mahesh K. Varanasi

Interference alignment is a transmission technique for exploiting all available degrees of freedom in the interference channel with an arbitrary number of users. Most prior work on interference alignment, however, neglects interference from…

Information Theory · Computer Science 2010-10-05 Steven W. Peters , Robert W. Heath

A multiplicity of autonomous terminals simultaneously transmits data streams to a compact array of antennas. The array uses imperfect channel-state information derived from transmitted pilots to extract the individual data streams. The…

Information Theory · Computer Science 2012-05-23 Hien Quoc Ngo , Erik G. Larsson , Thomas L. Marzetta

This paper studies a cell-free massive multiple-input multiple-output (MIMO) system where its access points (APs) and users are equipped with multiple antennas. Two transmission protocols are considered. In the first transmission protocol,…

Information Theory · Computer Science 2020-04-27 Trang C. Mai , Hien Quoc Ngo , Trung Q. Duong