Results 51 to 60 of about 107,082 (263)
A time-domain nearfield frequency-invariant beamforming method [PDF]
arXiv, 2021 Most existing beamforming methods are frequency-domain methods, and are designed for enhancing a farfield target source over a narrow frequency band. They have found diverse applications and are still under active development. However, they struggle to achieve desired performance if the target source is in the nearfield with a broadband output.
arxiv
Joint Design of Digital and Analog Processing for Downlink C-RAN with Large-Scale Antenna Arrays
, 2017 In millimeter-wave communication systems with large-scale antenna arrays, conventional digital beamforming may not be cost-effective. A promising solution is the implementation of hybrid beamforming techniques, which consist of low-dimensional digital ...
Kim, Jaein +4 more
core +1 more source
Open-Loop Beamforming Technique for MIMO System and Its Practical Realization
International Journal of Antennas and Propagation, 2011 The concept of close-loop beamforming for MIMO system was well known proposed the singular value decomposition on channel matrix. This technique can improve the capacity performance, but the cost of feedback channel and the complexity processing discard
Peerapong Uthansakul +2 more
doaj +1 more source
Beamformers for sparse recovery
2013 IEEE International Conference on Acoustics, Speech and Signal Processing, 2013 In sparse recovery from measurement data a common approach is to use greedy pursuit reconstruction algorithms. Most of these algorithms have a correlation filter for detecting active components in the sparse data. In this paper, we show how modifications can be made for the greedy pursuit algorithms so that they use beamformers instead of the standard ...
Sundin, Martin +2 more
openaire +4 more sources
, 2023 This chapter presents the fundamentals of the holography technique to form the beam in electromagnetic (EM) structures. The application of holography in leaky-wave antennas, metasurface reflectors, and reconfigurable intelligent surfaces (RISs) is explained. Consequently, different methods to analyze and realize an EM hologram are presented.
Ali, Araghi,, Mohsen, Khalily,
openaire +2 more sources
Sidelobe Suppression for Capon Beamforming with Mainlobe to Sidelobe Power Ratio Maximization [PDF]
, 2011 High sidelobe level is a major disadvantage of the Capon beamforming. To suppress the sidelobe, this paper introduces a mainlobe to sidelobe power ratio constraint to the Capon beamforming. it minimizes the sidelobe power while keeping the mainlobe power constant. Simulations show that the obtained beamformer outperforms the Capon beamformer.
arxiv +1 more source
Hybrid Beamforming via the Kronecker Decomposition for the Millimeter-Wave Massive MIMO Systems [PDF]
, 2017 Despite its promising performance gain, the realization of mmWave massive MIMO still faces several practical challenges. In particular, implementing massive MIMO in the digital domain requires hundreds of RF chains matching the number of antennas ...
Huang, Kaibin +5 more
core +2 more sources
Advanced Photonics Research, EarlyView.Optical wireless communications (OWCs) provide a promising alternative to spectrum‐congested microwave wireless communications. Recently, the use of metasurfaces with sub‐wavelength features for dynamic beam steering, beam manipulation, and spatial or optical‐angular‐momentum mode generation, conversion, and multiplexing in OWCs is proposed and ...
Ke Wang +7 more
wiley +1 more source
Opportunistic Scheduling and Beamforming for MIMO-OFDMA Downlink Systems with Reduced Feedback
, 2008 Opportunistic scheduling and beamforming schemes with reduced feedback are proposed for MIMO-OFDMA downlink systems. Unlike the conventional beamforming schemes in which beamforming is implemented solely by the base station (BS) in a per-subcarrier ...
Kim, Kyeong Jin +2 more
core +1 more source
Multiuser Beamforming for Partially-Connected Millimeter Wave Massive MIMO [PDF]
arXiv, 2023 Multiuser beamforming is considered for partially-connected millimeter wave massive MIMO systems. Based on perfect channel state information (CSI), a low-complexity hybrid beamforming scheme that decouples the analog beamformer and the digital beamformer is proposed to maximize the sum-rate.
arxiv