180 citations · 719 across the 46 of their papers we have counts for
28 papers · 1 filter
Hypertracking and Hyperrejection: Control of Signals beyond the Nyquist Frequency
Kaoru Yamamoto, Yutaka Yamamoto, Masaaki Nagahara
This paper studies the problem of signal tracking and disturbance rejection for sampled-data control systems, where the pertinent signals can reside beyond the so-called Nyquist fr…
Sparse Packetized Predictive Control of Disturbed Plants Over Channels with Data Loss
Mohsen Barforooshan, Masaaki Nagahara, Jan Ostergaard
This paper investigates closed-loop stability of a linear discrete-time plant subject to bounded disturbances when controlled according to packetized predictive control (PPC) polic…
CLOT Norm Minimization for Continuous Hands-off Control
Niharika Challapalli, Masaaki Nagahara, Mathukumalli Vidyasagar
In this paper, we consider hands-off control via minimization of the CLOT (Combined -One and Two) norm. The maximum hands-off control is the -optimal (or the sparsest) cont…
Min-Max Design of Feedback Quantizers for Netorwked Control Systems
Shuichi Ohno, Yuma Ishihara, Masaaki Nagahara
In a networked control system, quantization is inevitable to transmit control and measurement signals. While uniform quantizers are often used in practical systems, the overloading…
Continuous Hands-off Control by CLOT Norm Minimization
Niharika Challapalli, Masaaki Nagahara, Mathukumalli Vidyasagar
In this paper, we consider hands-off control via minimization of the CLOT (Combined L-One and Two) norm. The maximum hands-off control is the L0-optimal (or the sparsest) control a…
Rate-Distortion Analysis of Quantizers with Error Feedback
Shuichi Ohno, Teruyuki Shiraki, M. Rizwan Tariq +1
A Delta-Sigma modulator that is often utilized to convert analog signals into digital signals can be modeled as a static uniform quantizer with an error feedback filter. In this pa…
Characterization of maximum hands-off control
Debasish Chatterjee, Masaaki Nagahara, Daniel Quevedo +1
Maximum hands-off control aims to maximize the length of time over which zero actuator values are applied to a system when executing specified control tasks. To tackle such problem…
Maximum Hands-off Control without Normality Assumption
Takuya Ikeda, Masaaki Nagahara
Maximum hands-off control is a control that has the minimum L0 norm among all feasible controls. It is known that the maximum hands-off (or L0-optimal) control problem is equivalen…
Discrete-Valued Control by Sum-of-Absolute-Values Optimization
Takuya Ikeda, Masaaki Nagahara, Shunsuke Ono
In this paper, we propose a new design method of discrete-valued control for continuous-time linear time-invariant systems based on sum-of-absolute-values (SOAV) optimization. We f…
Digital Cancelation of Self-Interference for Single-Frequency Full-Duplex Relay Stations via Sampled-Data Control
Hampei Sasahara, Masaaki Nagahara, Kazunori Hayashi +1
In this article, we propose sampled-data design of digital filters that cancel the continuous-time effect of coupling waves in a single-frequency full-duplex relay station. In this…
Sampled-data Optimization for Self-interference Suppression in Baseband Signal Subspaces
Hampei Sasahara, Masaaki Nagahara, Kazunori Hayashi +1
In this article, we propose a design method of selfinterference cancelers for wireless relay stations taking account of the baseband signal subspace. The problem is first formulate…
Value Function in Maximum Hands-off Control
Takuya Ikeda, Masaaki Nagahara
In this brief paper, we study the value function in maximum hands-off control. Maximum hands-off control, also known as sparse control, is the L0-optimal control among the admissib…
Continuity of the Value Function in Sparse Optimal Control
Takuya Ikeda, Masaaki Nagahara
We prove the continuity of the value function of the sparse optimal control problem. The sparse optimal control is a control whose support is minimum among all admissible controls.…
Loop-Back Interference Suppression for OFDM Signals via Sampled-Data Control
Hampei Sasahara, Masaaki Nagahara, Kazunori Hayashi +1
In this article, we consider the problem of loop-back interference suppression for orthogonal frequency division multiplexing (OFDM) signals in amplify-and-forward single-frequency…
Sparsity Methods for Networked Control
Masaaki Nagahara
In this presentation, we introduce sparsity methods for networked control systems and show the effectiveness of sparse control. In networked control, efficient data transmission is…
Maximum Hands-Off Control: A Paradigm of Control Effort Minimization
M. Nagahara, D. E. Quevedo, D. Nesic
In this paper, we propose a new paradigm of control, called a maximum hands-off control. A hands-off control is defined as a control that has a short support per unit time. The max…
Sampled-Data H-infinity Design of Coupling Wave Cancelers in Single-Frequency Full-Duplex Relay Stations
Masaaki Nagahara, Hampei Sasahara, Kazunori Hayashi +1
In this article, we propose sampled-data H-infinity design of digital filters that cancel the continuous-time effect of coupling waves in a single-frequency full-duplex relay stati…
Hands-Off Control as Green Control
Masaaki Nagahara, Daniel E. Quevedo, Dragan Nesic
In this article, we introduce a new paradigm of control, called hands-off control, which can save energy and reduce CO2 emissions in control systems. A hands-off control is defined…
Sparse Command Generator for Remote Control
Masaaki Nagahara, Daniel E. Quevedo, Jan Ostergaard +2
In this article, we consider remote-controlled systems, where the command generator and the controlled object are connected with a bandwidth-limited communication link. In the remo…
Compressive Sampling for Networked Feedback Control
Masaaki Nagahara, Daniel E. Quevedo, Takahiro Matsuda +1
We investigate the use of compressive sampling for networked feedback control systems. The method proposed serves to compress the control vectors which are transmitted through rate…
Sparse Representations for Packetized Predictive Networked Control
Masaaki Nagahara, Daniel E. Quevedo
We investigate a networked control architecture for LTI plant models with a scalar input. Communication from controller to actuator is over an unreliable network which introduces p…
Monotone Smoothing Splines Using General Linear Systems
Masaaki Nagahara, Clyde F. Martin
In this paper, a method is proposed to solve the problem of monotone smoothing splines using general linear systems. This problem, also called monotone control theoretic splines, h…
Compressive Sampling for Remote Control Systems
Masaaki Nagahara, Takahiro Matsuda, Kazunori Hayashi
In remote control, efficient compression or representation of control signals is essential to send them through rate-limited channels. For this purpose, we propose an approach of s…
Sparsely-Packetized Predictive Control by Orthogonal Matching Pursuit
Masaaki Nagahara, Daniel E. Quevedo, Jan Ostergaard
We study packetized predictive control, known to be robust against packet dropouts in networked systems. To obtain sparse packets for rate-limited networks, we design control packe…