Listar por autor "González-Coma, José P."

Mostrando ítems 1-20 de 22

    • A Rank-Constrained Coordinate Ascent Approach to Hybrid Precoding for the Downlink of Wideband Massive (MIMO) Systems 

      González-Coma, José P.; Fresnedo, Óscar; Castedo, Luis (Institute of Electrical and Electronics Engineers, 2023-12)
      [Abstract]: An innovative approach to hybrid analog-digital precoding for the downlink of wideband massive MIMO systems is developed. The proposed solution, termed Rank-Constrained Coordinate Ascent (RCCA), starts seeking ...

    • Alternating Minimization for Wideband Multiuser IRS-Aided MIMO Systems Under Imperfect CSI 

      Pérez-Adán, Darian; Joham, Michael; Fresnedo, Óscar; González-Coma, José P.; Castedo, Luis; Utschick, Wolfgang (Institute of Electrical and Electronics Engineers, 2023-11-28)
      [Abstract]: This work focuses on wideband intelligent reflecting surface (IRS)-aided multiuser MIMO systems. One of the major challenges of this scenario is the joint design of the frequency-dependent base station (BS) ...

    • Channel Covariance Identification in FDD Massive MIMO Systems 

      González-Coma, José P.; Suárez-Casal, Pedro; Castro-Castro, Paula-María; Castedo, Luis; Joham, Michael (IEEE, 2018-11)
      [Abstract]: Many channel estimation methods in Massive MIMO FDD systems usually rely on the knowledge of the channel covariance matrix to operate. However, in real scenarios, this covariance is not known beforehand, and ...

    • Channel Estimation and Hybrid Precoding for Frequency Selective Multiuser mmWave MIMO Systems 

      González-Coma, José P.; Rodríguez-Fernández, Javier; Gonzalez-Prelcic, Nuria; Castedo, Luis; Heath, Robert W. (IEEE, 2018-05)
      [Abstract]: Configuring the hybrid precoders and combiners in a millimeter wave multiuser multiple-input multiple-output system is challenging in frequency selective channels. In this paper, we develop a system that uses ...

    • Coded Aperture Hyperspectral Image Reconstruction 

      García-Sánchez, Ignacio; Fresnedo, Óscar; González-Coma, José P.; Castedo, Luis (MDPI, 2021)
      [Abstract] In this work, we study and analyze the reconstruction of hyperspectral images that are sampled with a CASSI device. The sensing procedure was modeled with the help of the CS theory, which enabled efficient ...

    • Design of Linear Precoders for Correlated Sources in MIMO Multiple Access Channels 

      Suárez-Casal, Pedro; González-Coma, José P.; Fresnedo, Óscar; Castedo, Luis (Institute of Electrical and Electronics Engineers, 2018-12)
      [Abstract]: This paper focuses on distributed linear precoding when users transmit correlated information over a fading multiple-input and multiple-output multiple access channel. The precoders are optimized in order to ...

    • Evaluation of Analog Joint Source-Channel Coding Systems for Multiple Access Channels 

      Fresnedo, Óscar; González-Coma, José P.; Hassanin, Mohamed; Castedo, Luis; Garcia-Frias, Javier (Institute of Electrical and Electronics Engineers, 2015-06)
      [Abstract]: We address the evaluation of low-complexity analog Joint Source Channel Coding (JSCC) methods for the transmission of discrete-time analog symbols over Multiple-Input Multiple-Output (MIMO) Multiple Access ...

    • Exploring the Feasibility of Low Cost Technology in Rainfall Monitoring: The TREBOADA Observing System 

      Fraga, Ignacio; Alvarellos, Alberto; González-Coma, José P. (M D P I AG, 2019-07-22)
      [Abstract] In order to characterize the spatial and temporal variability of the rainfall, we have developed an observation system to monitor the precipitation over the metropolitan area of A Coruña. The observation system ...

    • FDD Channel Estimation Via Covariance Estimation in Wideband Massive MIMO Systems 

      González-Coma, José P.; Suárez-Casal, Pedro; Castro-Castro, Paula-María; Castedo, Luis (M D P I AG, 2020-02-10)
      [Abstract] A method for channel estimation in wideband massive Multiple-Input Multiple-Output systems using hybrid digital analog architectures is developed. The proposed method is useful for Frequency-Division Duplex at ...

    • Hybrid LISA for Wideband Multiuser Millimeter-Wave Communication Systems Under Beam Squint 

      González-Coma, José P.; Utschick, Wolfgang; Castedo, Luis (IEEE, 2019-02)
      [Abstract]: This paper jointly addresses user scheduling and precoder/combiner design in the downlink of a wideband millimeter-wave communications system. We consider the orthogonal frequency-division multiplexing modulation ...

    • Hybrid Precoding With Time-Modulated Arrays for Mmwave MIMO Systems 

      González-Coma, José P.; Maneiro-Catoira, Roberto; Castedo, Luis (Institute of Electrical and Electronics Engineers, 2018)
      [Abstract]: We consider the utilization of time-modulated arrays (TMAs) as a simple and cost-effective approach to hybrid digital–analog precoding in millimeter wave (mmWave) multiple-input multiple-output (MIMO) systems. ...

    • Intelligent Reflective Surfaces for Wireless Networks: An Overview of Applications, Approached Issues, and Open Problems 

      Pérez-Adán, Darian; Fresnedo, Óscar; González-Coma, José P.; Castedo, Luis (MDPI, 2021)
      [Abstract] An intelligent reflective surface (IRS) is a novel and revolutionizing communication technology destined to enable the control of the radio environment. An IRS is a real-time controllable reflectarray with a ...

    • Low-Complexity Distance-Based Scheduling for Multi-User XL-MIMO Systems 

      González-Coma, José P.; Lopez-Martinez, F.J.; Castedo, Luis (IEEE, 2021-11)
      [Abstract]: We introduce Distance-Based Scheduling (DBS), a new technique for user selection in downlink multi-user communications with extra-large (XL) antenna arrays. DBS categorizes users according to their equivalent ...

    • Performance of MIMO systems in measured indoor channels with transmitter noise 

      Castro-Castro, Paula-María; González-Coma, José P.; García-Naya, José A.; Castedo, Luis (Springer, 2012)
      This study analyzes the impact of transmitter noise on the performance of multiple-input multiple-output (MIMO) systems with linear and nonlinear receivers and precoders. We show that the performance of MIMO linear and ...

    • Power Efficient Scheduling and Hybrid Precoding for Time Modulated Arrays 

      González-Coma, José P.; Castedo, Luis (Institute of Electrical and Electronics Engineers, 2020-01-22)
      [Abstract] We consider power efficient scheduling and precoding solutions for multiantenna hybrid digital-analog transmission systems that use Time-Modulated Arrays (TMAs) in the analog domain. TMAs perform beamforming ...

    • QoS constrained power minimization in the MISO broadcast channel with imperfect CSI 

      González-Coma, José P.; Joham, Michael; Castro-Castro, Paula-María; Castedo, Luis (Elsevier, 2017-02)
      [Abstract]: In this paper we consider the design of linear precoders and receivers in a Multiple-Input Single-Output (MISO) Broadcast Channel (BC). We aim to minimize the transmit power while meeting a set of per-user ...

    • QoS constrained power minimization in the multiple stream MIMO broadcast channel 

      González-Coma, José P.; Joham, Michael; Castro-Castro, Paula-María; Castedo, Luis (Elsevier, 2018-02)
      [Abstract]: This work addresses the design of optimal linear transmit filters for the Multiple Input-Multiple Output (MIMO) Broadcast Channel (BC) when several spatial streams are allocated to each user. We further consider ...

    • Quality of service optimization in the Broadcast Channel with Imperfect transmit channel state information 

      González-Coma, José P. (2015)
      [Resumen]Este trabajo considera un sistema Broadcast Channel (BC) que consiste en un transmisor equipado con múltiples antenas y varios usuarios con una o más antenas. Dependiendo del número de antenas en el lado receptor, ...

    • Rank Constrained Precoding for the Downlink of mmWave Massive MIMO Hybrid Systems 

      González-Coma, José P.; Fresnedo, Óscar; Castedo, Luis (Institute of Electrical and Electronics Engineers, 2021-02-11)
      [Abstract] The hybrid design of precoding schemes for millimeter-wave communications allows exploiting the gains by using large antenna array with an affordable hardware cost and power consumption. In this work, we present ...

    • User Grouping for the Uplink of Multiuser Hybrid mmWave MIMO 

      Pérez-Adán, Darian; Fresnedo, Óscar; González-Coma, José P.; Castedo, Luis (Institute of Electrical and Electronics Engineers, 2020-03-16)
      [Abstract] Hybrid analog/digital schemes for precoding/combining have proved to be a low-complexity and/or low-power strategy to obtain reasonable beamforming gains in multiuser millimeter-wave (mmWave) multiple-input ...