activity
20182026
most citedOFDM with Index Modulation in Orbital Angular Momentum Multiplexed Free Space Optical Links

27 citations · 34 across the 5 of their papers we have counts for

collaborators
Showing eess.SPShow all

13 papers · 1 filter

eess.SP2026

Estimating PLL Phase Noise Parameters from Measurements for System-Level Modeling

Carl Collmann, Ahmad Nimr, Gerhard Fettweis

In current MIMO mobile communication systems, phase noise can significantly impair performance. To allow for compensation of these impairments, accurate phase noise modeling is nec…

eess.SP2026

Proof of Concept: Local TX Real-Time Phase Calibration in MIMO Systems

Carl Collmann, Ahmad Nimr, Gerhard Fettweis

Channel measurements in MIMO systems hinge on precise synchronization. While methods for time and frequency synchronization are well established, maintaining real-time phase cohere…

eess.SP2026

Cramer-Rao Bound for Angle of Arrival Estimates in True-Time-Delay Systems

Carl Collmann, Ahmad Nimr, Gerhard Fettweis

In the context of joint communication and sensing JC&S, the challenge of obtaining accurate parameter estimates is of interest. Parameter estimates, such as the AoA can be utilized…

eess.SP2025

A Practical Analysis: Understanding Phase Noise Modelling in Time and Frequency Domain for Phase-Locked Loops

Carl Collmann, Bitan Banerjee, Ahmad Nimr +1

In MIMO systems, the presence of phase noise is a significant factor that can degrade performance. For MIMO testbeds build from SDR devices, phase noise cannot be ignored, particul…

eess.SP2025

Cross-layer Integrated Sensing and Communication: A Joint Industrial and Academic Perspective

Henk Wymeersch, Nuutti Tervo, Stefan Wänstedt +40

Integrated sensing and communication (ISAC) enables radio systems to simultaneously sense and communicate with their environment. This paper, developed within the Hexa-X-II project…

eess.SP20217 cited

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…