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Related papers: Spectral Efficiency of Random Time-Hopping CDMA

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This paper proposes a novel time-frequency warped waveform for short symbols, massive machine-type communication (mMTC), and internet of things (IoT) applications. The waveform is composed of asymmetric raised cosine (RC) pulses to increase…

Signal Processing · Electrical Eng. & Systems 2024-10-28 Mostafa Ibrahim , Huseyin Arslan , Hakan Ali Cirpan , Sabit Ekin

In this paper, a new detection algorithm is proposed for turbo coded Code Division Multiple Access (CDMA) signals in detect and forward cooperative channels. Use of user cooperation makes much improvement in the performance of CDMA systems.…

Signal Processing · Electrical Eng. & Systems 2018-03-13 Ebrahim Karami

Nodes movements play a significant role in disseminating messages in the sparse mobile ad-hoc network. In the network scenarios, where traditional end-to-end paths do not exist, mobility creates opportunities for nodes to connect and…

Networking and Internet Architecture · Computer Science 2013-05-07 Hemal Shah , Yogeshwar Kosta , Vikrant Patel

In this paper, the performance of a dual-hop relaying terahertz (THz) wireless communication system is investigated. In particular, the behaviors of the two THz hops are determined by three factors, which are the deterministic path loss,…

Information Theory · Computer Science 2021-07-29 Sai Li , Liang Yang

This paper studies energy efficient resource allocation for a machine-to-machine (M2M) enabled cellular network with non-linear energy harvesting, especially focusing on two different multiple access strategies, namely non-orthogonal…

Information Theory · Computer Science 2017-11-30 Zhaohui Yang , Wei Xu , Yijin Pan , Cunhua Pan , Ming Chen

The central issue in direct-sequence code-division multiple-access (DS-CDMA) ad hoc networks is the prevention of a near-far problem. This paper considers two types of guard zones that may be used to control the near-far problem: a…

Information Theory · Computer Science 2012-09-20 Don Torrieri , Matthew C. Valenti

Spatial division multiple access (SDMA) is essential to improve the spectrum efficiency for multi-user multiple-input multiple-output (MIMO) communications. The classical SDMA for massive MIMO with hybrid precoding heavily relies on the…

Signal Processing · Electrical Eng. & Systems 2023-01-24 Zidong Wu , Linglong Dai

We investigate energy-efficiency issues and resource allocation policies for time division multi-access (TDMA) over fading channels in the power-limited regime. Supposing that the channels are frequency-flat block-fading and transmitters…

Information Theory · Computer Science 2007-07-13 Xin Wang , Georgios B. Giannakis

The central issue in direct-sequence code-division multiple-access (DS-CDMA) ad hoc networks is the prevention of a near-far problem. This paper considers two types of guard zones that may be used to control the near-far problem: a…

Information Theory · Computer Science 2013-04-22 Don Torrieri , Matthew C. Valenti

Many new narrowband low-power wide-area networks (LPWANs) (e.g., LoRaWAN, Sigfox) have opted to use pure ALOHA-like access for its reduced control overhead and asynchronous transmissions. Although asynchronous access reduces the energy…

Information Theory · Computer Science 2021-01-20 Luca Beltramelli , Aamir Mahmood , Paolo Ferrari , Patrik Österberg , Mikael Gidlund , Emiliano Sisinni

In the recent papers [1-4] including above paper time modulated frequency diverse arrays (FDAs) have been presented to obtain time invariant spatial patterns. The presented FDAs in [1-3] have the feature of time-invariant spatial focusing…

Signal Processing · Electrical Eng. & Systems 2019-12-03 Mahdi Fartookzadeh

This work introduces a new perspective for physical media sharing in multiuser communication by jointly considering (i) the meaning of the transmitted message and (ii) its function at the end user. Specifically, we have defined a scenario…

Tomlinson-Harashima precoding (THP) is a nonlinear processing technique employed at the transmit side and is a dual to the successive interference cancelation (SIC) detection at the receive side. Like SIC detection, the performance of THP…

Information Theory · Computer Science 2016-11-15 K. Zu , R. C. de Lamare , M. Haardt

Code-division multiple-access (CDMA) has the potential to support traffic sources with a wide range of quality of service (QoS) requirements. The traffic carrying capacity of CDMA channels under QoS constraints (such as delay guarantee) is,…

Networking and Internet Architecture · Computer Science 2011-05-03 Kashif Mahmood , Mikko Vehkaperä , Yuming Jiang

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

In this paper, we propose a joint time-frequency splitting (TFS) strategy for a multiuser orthogonal frequency division multiplexing (OFDM) system with simultaneous wireless information and power transfer (SWIPT). In TFS, the time sharing…

Signal Processing · Electrical Eng. & Systems 2019-02-11 Zhaohui Yang , Wei Xu , Mohammad Shikh-Bahaei

Sparse code multiple access (SCMA) is a new frequency domain non-orthogonal multiple-access technique which can improve spectral efficiency of wireless radio access. With SCMA, different incoming data streams are directly mapped to…

Information Theory · Computer Science 2016-11-18 Hosein Nikopour , Eric Yi , Alireza Bayesteh , Kelvin Au , Mark Hawryluck , Hadi Baligh , Jianglei Ma

This letter proposes a Message Passing (MP) based algorithm for demodulating the time-encoded digital modulation signal. The proposed algorithm processes the spikes generated by the Time-Encoding Machine (TEM) directly on a per-spike basis,…

Signal Processing · Electrical Eng. & Systems 2025-12-09 Yuan Xu , Wenhui Xiong

The frequency selectivity of wireless communication channels can be characterized by the delay spread Ds of the channel impulse response. If the delay spread is small compared to the bandwidth W of the input signal, that is, Ds*W…

Information Theory · Computer Science 2008-08-07 Georg Böcherer , Daniel Bielefeld

In the literature, asymptotic studies of multi-hop wireless network capacity often consider only centralized and deterministic TDMA (time-division multi-access) coordination schemes. There have been fewer studies of the asymptotic capacity…

Networking and Internet Architecture · Computer Science 2017-09-25 Chi-Kin Chau , Minghua Chen , Soung Chang Liew
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