14 papers
Making AFDM Secure Against Eavesdroppers: A Phase Function Design Approach
Hengxuan Liu, Vincent Savaux, Arman Farhang
Affine frequency division multiplexing (AFDM) has recently emerged as a promising waveform for high-mobility communications due to its resilience to Doppler effects and its advanta…
Joint Phase Noise and Channel Estimation for OTFS
Stephen McWade, Arman Farhang
This paper investigates the effect of oscillator phase noise in orthogonal time frequency space (OTFS) systems. The paper provides in-depth analysis of the interference due to phas…
Multiuser OTFS Channel Parameter Estimation Toward Grid-Independent Regime
Hanning Wang, Rong-Rong Chen, Arman Farhang
We study channel parameter estimation for multiuser orthogonal time frequency space (OTFS) systems in the delay-Doppler (DD) domain. To enable structured parametric estimation, we…
HAPS-RIS and UAV Integrated Networks: A Unified Joint Multi-objective Framework
Arman Azizi, Mostafa Rahmani Ghourtani, Mustafa A. Kishk +2
Future 6G non-terrestrial networks aim to deliver ubiquitous connectivity to remote and undeserved regions, but unmanned aerial vehicle (UAV) base stations face fundamental challen…
Channel Estimation using 5G Sounding Reference Signals: A Delay-Doppler Domain Approach
Danilo Lelin Li, Ramtin Rabiee, Arman Farhang
Delay-Doppler multicarrier modulation (DDMC) techniques have been among the central topics of research for high-Doppler channels. However, a complete transition to DDMC-based wavef…
Towards Standardizing OTFS: A Candidate Waveform for Next-Generation Wireless Networks
Mingcheng Nie, Ruoxi Chong, Shuangyang Li +5
The standardization of the sixth-generation (6G) has recently commenced to address the rapidly growing demands for enhanced wireless network services. Nevertheless, existing wirele…
Unique Word Channel Estimation for Oversampled OTFS
Radim Zedka, Roman Marsalek, Marek Bobula +1
Practical aspects of orthogonal time frequency space (OTFS), such as channel estimation and its performance in fractional delay-Doppler (DD) channels, are a lively topic in the OTF…
Waveform-domain NOMA: An Enabler for ISAC in Uplink Transmission
Jialiang Zhu, Hamza Haif, Abdelali Arous +2
According to the recent 3GPP decisions on 6G air interface, orthogonal frequency-division multiplexing (OFDM)-based waveforms are the primary candidates for future integrated sensi…
A Unified Framework for Adaptive Waveform Processing in Next Generation Wireless Networks
Abdelali Arous, Hamza Haif, Arman Farhang +1
The emergence of alternative multiplexing domains to the time-frequency domains, e.g., the delay-Doppler and chirp domains, offers a promising approach for addressing the challenge…
Time and Frequency Synchronization for Multiuser OTFS in Uplink
Mohsen Bayat, Sanoopkumar P. S., Arman Farhang
In this paper, we propose time and frequency synchronization techniques for uplink multiuser OTFS (MU-OTFS) systems in high-mobility scenarios. This work focuses on accurately esti…
PAPR of DFT-s-OTFS with Pulse Shaping
Jialiang Zhu, Sanoopkumar P. S., Arman Farhang
Orthogonal Time Frequency Space (OTFS) suffers from high peak-to-average power ratio (PAPR) when the number of Doppler bins is large. To address this issue, a discrete Fourier tran…
Time Frequency Localized Pulse for Delay Doppler Domain Data Transmission
Sanoopkumar P. S, Muyiwa Balogun, Liam Barry +1
Orthogonal time frequency space (OTFS) is a strong candidate waveform for sixth generation wireless communication networks (6G), which can effectively handle time varying wireless…
Windowed Dictionary Design for Delay-Aware OMP Channel Estimation under Fractional Doppler
Hanning Wang, Xiang Huang, Rong-Rong Chen +1
Delay-Doppler (DD) signal processing has emerged as a powerful tool for analyzing multipath and time-varying channel effects. Due to the inherent sparsity of the wireless channel i…
Exploring the Impact of HAPS-RIS on UAV-Based Networks: a Novel Network Architecture
Arman Azizi, Mustafa A. Kishk, Arman Farhang
In this paper, we propose a network architecture where two types of aerial infrastructures together with a ground station provide connectivity to a remote area. A high altitude pla…