Joseph Carlson

dblp:337/8167 · DBLP profile ↗
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7ranked-venue papers
4as first author
7since 2021 · last 2026
0009-0001-7847-0956ORCID · corroborated

Domains — the database's venue-derived domains; a paper can count in several

Computer networks · 7 · 4 first-author · 7 since 2021
YearPublicationVenuePosition
2026 Frequency-Selective Beamforming and Single-Shot Beam Training With Dynamic Metasurface Antennas
abstract
Dynamic metasurface antennas (DMAs) are leaky-wave antennas with frequency-reconfigurable slots. While resonant frequency of individual slots on the DMA can be independently configured in a wide frequency range, the DMA’s beamforming performance across different operating frequencies in the available range has not been studied yet. We show that the dominant beam direction and the operating frequency of a DMA are interdependent. Using this observation, we derive a closed-form expression for line-of-sight (LOS) beamforming gain maximization to jointly configure the operating frequency and per-slot resonant frequency configuration of the DMA. A benefit of this approach in the LOS channel case is that all slots are tuned to the same resonant frequency, eliminating the need for a computationally expensive search across all feasible resonant frequency configurations. We also apply this approach to mitigate beam training overhead in large arrays by proposing a single-shot beam training algorithm that estimates the optimal resonant frequency configuration through simultaneous probing of multiple angular directions across frequencies. Simulation results show that our proposed approach offers a comparable achievable rate to true-time-delay (TTD) based systems, but with lower power consumption and hardware cost.
Nitish Deshpande 0001, Joseph Carlson, Miguel R. Castellanos, Robert W. Heath Jr.
IEEE Trans. Commun.2
2026 Power Scaling Law of Superdirective Multi-User Beamforming in Compact Arrays
abstract
Traditional antenna arrays with a half-wavelength spacing between elements are capable of achieving a power gain proportional to the number of antennasM. Superdirective antenna arrays, however, leverage smaller antenna spacing to approach an achievable power gain ofM2, which could provide a significant performance improvement to the spectral efficiency in wireless communication systems. In this paper, we study the power scaling law of superdirective beamforming in multi-user communication systems using a uniform linear array (ULA). First, we extend superdirective precoding from single-user to multi-user multipath scenarios. Employing the basis of Legendre polynomials, we prove that the scaling laws of both the power gain and signal-to-interference-plus-noise ratio (SINR) are betweenMandM2, whereM2is achieved in the end-fire direction. To further enhance user power gains and effectively manage interference, we formulate and solve an optimization problem that maximizes the directivity gain while nullifying interference to other users. We demonstrate that this scheme can significantly improve spectral efficiency in multi-user settings, even when antenna spacing approaches zero. Moreover, we address the narrow directivity bandwidth issue, showing that the directivity of superdirective arrays decreases sharply as the frequency moves away from the center frequency, necessitating the use of multi-carrier technology to overcome this limitation. Simulation results verify the proposed power scaling law and show significant improvements in spectral efficiency with our proposed methods compared to a traditional antenna array with half-wavelength spacing.
Liangcheng Han, Haifan Yin, Robert W. Heath Jr., Joseph Carlson
IEEE Trans. Commun.4
2026 Wideband Dynamic Metasurface Antenna Performance With Practical Design Characteristics
abstract
Dynamic metasurface antennas (DMA) provide low-power beamforming through reconfigurable radiative slots. Each slot has a tunable component that consumes low power compared to typical analog components like phase shifters. This makes DMAs a potential candidate to minimize the power consumption of multiple-input multiple-output (MIMO) antenna arrays. In this paper, we investigate the use of DMAs in a wideband communication setting with practical DMA design characteristics. We develop approximations for the DMA beamforming gain that account for the effects of waveguide attenuation, element frequency-selectivity, and limited reconfigurability of the tunable components as a function of the signal bandwidth. The approximations allow for key insights into the wideband performance of DMAs in terms of different design variables. We develop a simple successive beamforming algorithm to improve the wideband performance of DMAs by sequentially configuring each DMA element. Simulation results for a line-of-sight (LOS) wideband system show the accuracy of the approximations with the simulated DMA model in terms of spectral efficiency. We also find that the proposed successive beamforming algorithm increases the overall spectral efficiency of the DMA-based wideband system compared with a baseline DMA beamforming method.
Joseph Carlson, Nitish Deshpande 0001, Miguel R. Castellanos, Robert W. Heath Jr.
IEEE Trans. Wirel. Commun.1
2025 A Wideband Beamforming Algorithm for Dynamic Metasurface Antennas Under Realistic Constraints
abstract
A dynamic metasurface antenna (DMA) is a slottedwaveguide antenna with tunable components that allow for beamforming with low power consumption. The resonant frequencies of the individual DMA slot elements are reconfigurable, which can be leveraged for wideband communications to support larger bandwidths. The vast majority of prior work on DMAs focuses on narrowband applications for DMAs. In this paper, we develop a beamforming algorithm to improve the performance of a multicarrier DMA-based wireless system with large signal bandwidths. We build upon prior DMA signal models to incorporate different frequency-selective aspects of the physical DMA elements, and investigate the impact of different DMA designs on wideband performance. We find that the proposed beamforming algorithm outperforms a baseline beamforming algorithm in terms of spectral efficiency and data rates under significant frequencyselectivity in the multi-carrier channel and DMA elements.
Joseph Carlson, Nitish Deshpande 0001, Miguel R. Castellanos, Robert W. Heath Jr.
ICC1
2025 Frequency-Selective Beamforming with Dynamic Metasurface Antennas
abstract
Dynamic metasurface antennas (DMAs) enable beamforming through low-power components that reconfigure each radiating element. Previous studies on a single user multiple-input-single-output (MISO) system with transmit DMA focused on maximizing beamforming gain in narrowband scenarios. In this paper, we analyze the beamforming performance of DMAs in wideband scenarios. By leveraging DMA's frequency reconfigurability, our proposed approach dynamically adjusts both the transmission frequency and element configuration, achieving a higher beamforming gain than the narrowband method. We also propose the optimal waveguide refractive index and DMA element spacing to obtain an equal beamforming gain as the power hungry true-time-delay (TTD) architecture in the desired angular range. We evaluate the achievable rate performance and show that the rate approaches that of TTD when the DMA tuning range increases.
Nitish Deshpande 0001, Joseph Carlson, Miguel R. Castellanos, Robert W. Heath Jr.
ICC2
2024 Hierarchical Codebook Design With Dynamic Metasurface Antennas for Energy-Efficient Arrays
abstract
Dynamic metasurface antennas (DMA) provide a solution to form compact, cost-effective, energy-efficient multiple-input-multiple output (MIMO) arrays. In this paper, we implement a practical hierarchical codebook with a realistic DMA design through electromagnetic simulations. We leverage existing DMA models to derive a novel method for enhancing the beamforming gain. We find that the proposed method provides better coverage and spectral efficiency results than prior methods. We also present and verify a new technique for creating wide beamwidths through the DMA and hierarchical codebook. Additionally, we use a detailed transmitter architecture model to determine the power consumption savings of the DMA compared to a typical phased array. The DMA largely outperforms a passive phased array in terms of spectral and energy efficiency due to high component loss from a high-resolution passive phase shifter. While the DMA provides lower spectral efficiency results than the active phased array, the DMA achieves a higher energy efficiency because of the significant power consumption for the active phase shifters. Therefore, we find that DMAs in a realistic wireless environment provide sufficient coverage and spectral efficiency compared to typical phased arrays while maintaining a substantially lower power consumption.
Joseph Carlson, Miguel R. Castellanos, Robert W. Heath Jr.
IEEE Trans. Wirel. Commun.1
2023 Dynamic Metasurface Antennas for Energy-Efficient MISO Communications
abstract
Dynamic metasurface antennas (DMA) have been proposed for massive multiple-input multiple-output (MIMO) and millimeter wave applications due to their ability to create dense, energy-efficient arrays. In this paper, we integrate DMAs into a realistic wireless environment to compare their performance in spectral and energy efficiency with a conventional phased array. We implement a practical transmitter architecture for the DMA and phased array to account for the power consumption and hardware constraints of the radio frequency (RF) front end. Simulation results for a MISO scenario show that while the DMA performs worse in spectral efficiency than an active phased array, the power consumption savings from the reconfigurable component enable better performance in energy efficiency. Therefore, DMAs can provide an energy-efficient alternative to typical phased arrays.
Joseph Carlson, Miguel R. Castellanos, Robert W. Heath Jr.
GLOBECOM1