Results 41 to 50 of about 741,207 (289)
Spectral Efficiency of Random Time-Hopping CDMA
, 2015 Traditionally paired with impulsive communications, Time-Hopping CDMA (TH-CDMA) is a multiple access technique that separates users in time by coding their transmissions into pulses occupying a subset of $N_\mathsf{s}$ chips out of the total $N$ included
Di Benedetto, Maria-Gabriella +1 more
core +3 more sources
Characterization of wavelength interleaving in radio-over-fiber systems employing WDM/SCM [PDF]
, 2006 A radio-over-fiber (RoF) distribution system incorporating both sub-carrier multiplexing and wavelength division multiplexing (WDM) technologies is presented. This signal is directly modulated onto three high-speed lasers.
A. Kaszubowska +10 more
core +1 more source
Information, 2018 In recent years, there has been a rapid evolution of wireless technologies that has led to the challenge of high demand for spectral resources. To overcome this challenge, good spectrum management is required that calls for more efficient use of the ...
Prince Semba Yawada, Mai Trung Dong
doaj +1 more source
Sensors, 2023 Full-duplex (FD) and reconfigurable intelligent surface (RIS) are potential technologies for achieving wireless communication effectively. Therefore, in theory, the RIS-aided FD system is supposed to enhance spectral efficiency significantly for the ...
Kunbei Pan +3 more
doaj +1 more source
Spectral Efficiency of Mixed-ADC Massive MIMO
, 2018 We study the spectral efficiency (SE) of a mixed-ADC massive MIMO system in which K single-antenna users communicate with a base station (BS) equipped with M antennas connected to N high-resolution ADCs and M-N one-bit ADCs.
Pirzadeh, Hessam, Swindlehurst, A. Lee
core +1 more source
High-power 1.3 µm superluminescent diode [PDF]
, 1989 Superluminescent diodes with high output power (10 mW at 175 mA), wide spectral width (28 nm), low spectral modulation depth (
Bar-Chaim, Nadav +2 more
core +1 more source
An Enhanced DCO-OFDM Scheme for Dimming Control in Visible Light Communication Systems
IEEE Photonics Journal, 2016 In visible light communication (VLC) systems, optical orthogonal frequency-division multiplexing (O-OFDM) is an appealing modulation scheme. Recently, a number of O-OFDM schemes have been proposed. Among them, direct-current O-OFDM (DCO-OFDM) is a widely
Yang Yang +3 more
doaj +1 more source
Spectral Efficiency Improvement and Power Control Optimization of Massive MIMO Networks
IEEE Access, 2021 Higher requirements must be put forward about wireless signal transmission in harsh environments. Energy loss mitigation, channel estimation, noise interference reduction demands high quality of service in wireless communication.
Xiu Zhang, Hao Qi, Xin Zhang, Liang Han
doaj +1 more source
Impact of Spectrum Sharing on the Efficiency of Faster-Than-Nyquist Signaling
, 2014 Capacity computations are presented for Faster-Than-Nyquist (FTN) signaling in the presence of interference from neighboring frequency bands. It is shown that Shannon's sinc pulses maximize the spectral efficiency for a multi-access channel, where ...
Hefnawy, Marwa El, Kramer, Gerhard
core +1 more source
IEEE Access, 2023 This paper focuses on investigating uplink (UL) data transmission in cell-free massive MIMO based on orthogonal frequency division multiplexing (CF-mMIMO-OFDM) systems, taking into account the effects of hardware impairments (HWIs).
Asma Mabrouk, Rafik Zayani
doaj +1 more source