Doğa Gürgünoğlu

• Master of Science
• Doctoral Student at KTH Royal Institute of Technology

In this letter, we address parametric channel estimation in a multi-user multiple-input multiple-output system within the radiative near-field of the base station array with aperture antennas. We investigate a two-dimensional multiple signal classification algorithm (2D-MUSIC) to estimate both the range and the azimuth angles of arrival for the use...

In this letter, we investigate the use of reconfigurable intelligent surfaces (RISs) to jointly estimate the position and channel of a user equipment (UE) using uplink pilot signals. We consider a setup with a user and a base station (BS), where the direct path between the BS and the UE is blocked and virtual line-of-sight (LOS) links are created o...

In this paper, we study a new kind of pilot contamination appearing in multi-operator reconfigurable intelligent surfaces (RIS) assisted networks, where multiple operators provide services to their respective served users. The operators use dedicated frequency bands, but each RIS inadvertently reflects the transmitted uplink signals of the user equ...

In this paper, we study the impact of pilot contamination in a system where two operators serve their respective users with the assistance of two wide-band reconfigurable intelligent surfaces (RIS), each belonging to a single operator. We consider one active user per operator and they use disjoint narrow frequency bands. Although each RIS is dedica...

In the uplink of multiuser multiple input multiple output (MU-MIMO) systems operating over aging channels, pilot spacing is crucial for acquiring channel state information and achieving high signal-to-interference-plus-noise ratio (SINR). Somewhat surprisingly, very few works examine the impact of pilot spacing on the correlation structure of subse...

We investigate the joint transmit beamforming and reconfigurable intelligent surface (RIS) configuration problem to maximize the sum downlink rate of a RIS-aided cellular multiuser multiple input single output (MU-MISO) system under imperfect channel state information (CSI) and hardware impairments by considering a practical phase-dependent RIS amp...

In the uplink of multiuser multiple input multiple output (MU-MIMO) systems operating over aging channels, pilot spacing is crucial for acquiring channel state information and achieving high signal-to-interference-plus-noise ratio (SINR). Somewhat surprisingly, very few works examine the impact of pilot spacing on the correlation structure of subse...

The optimal power adaptation problem is investigated for vector parameter estimation according to various Fisher information based optimality criteria. By considering an observation model that involves a linear transformation of the parameter vector and an additive noise component with an arbitrary probability distribution, six different optimal po...

Optimal power allocation for secure estimation of multiple deterministic parameters is investigated under a total power constraint. The goal is to minimize the Cramer-Rao lower bound (CRLB) at an intended receiver while keeping estimation errors at an eavesdropper above specified target levels. To that end, an optimization problem is formulated by...

The optimal power adaptation problem is investigated for vector parameter estimation according to various Fisher information based optimality criteria. By considering a generic observation model that involves a linear/nonlinear transformation of the parameter vector and an additive noise component with an arbitrary probability distribution, six dif...