27 citations · 34 across the 3 of their papers we have counts for
7 papers
Channel Estimation for MIMO Space Time Coded OTFS under Doubly Selective Channels
Roberto Bomfin, Marwa Chafii, Ahmad Nimr +1
In this paper, we present a unique word (UW)-based channel estimation approach for multiple-input multiple-output (MIMO) systems under doubly dispersive channels, which is applied…
OFDM with Index Modulation in Orbital Angular Momentum Multiplexed Free Space Optical Links
El-Mehdi Amhoud, Marwa Chafii, Ahmad Nimr +1
Communication using orbital angular momentum (OAM) modes has recently received a considerable interest in free space optical (FSO) communications. Propagating OAM modes through fre…
In-phase and Quadrature Chirp Spread Spectrum for IoT Communications
Ivo Bizon Franco de Almeida, Marwa Chafii, Ahmad Nimr +1
This paper describes a coherent chirp spread spectrum (CSS) technique based on the Long-Range (LoRa) physical layer (PHY) framework. LoRa PHY employs CSS on top of a variant of fre…
Practical GFDM-based Linear Receivers
Ahmad Nimr, Marwa Chafii, Gerhard Fettweis
The conventional receiver designs of generalized frequency division multiplexing (GFDM) consider a large scale multiple-input multiple-output (MIMO) system with a block circular ma…
Unified Low Complexity Radix-2 Architectures for Time and Frequency-domain GFDM Modem
Ahmad Nimr, Marwa Chafii, Gerhard Fettweis
Most of the conventional multicarrier waveforms explicitly or implicitly involve a generalized frequency division multiplexing (GFDM)-based modem as a core part of the baseband pro…
Extended GFDM Framework: OTFS and GFDM Comparison
Ahmad Nimr, Marwa Chafii, Maximilian Matthe +1
Orthogonal time frequency space modulation (OTFS) has been recently proposed to achieve time and frequency diversity, especially in linear time-variant (LTV) channels with large Do…