180 citations · 719 across the 46 of their papers we have counts for
20 papers · 1 filter
Multirate Digital Signal Processing via Sampled-Data H-infinity Optimization
Masaaki Nagahara
In this thesis, we present a new method for designing multirate signal processing and digital communication systems via sampled-data H-infinity control theory. The difference betwe…
YY Filter - A Paradigm of Digital Signal Processing
Masaaki Nagahara
YY filter, named after the founder Prof. Yutaka Yamamoto, is a digital filter designed by sampled-data control theory, which can optimize the analog performance of the signal proce…
Active Noise Control with Sampled-Data Filtered-x Adaptive Algorithm
Masaaki Nagahara, Ken-ichi Hamaguchi, Yutaka Yamamoto
Analysis and design of filtered-x adaptive algorithms are conventionally done by assuming that the transfer function in the secondary path is a discrete-time system. However, in re…
H-infinity Design of Periodically Nonuniform Interpolation and Decimation for Non-Band-Limited Signals
Masaaki Nagahara, Masaki Ogura, Yutaka Yamamoto
In this paper, we consider signal interpolation of discrete-time signals which are decimated nonuniformly. A conventional interpolation method is based on the sampling theorem, and…
H-infinity Optimal Approximation for Causal Spline Interpolation
Masaaki Nagahara, Yutaka Yamamoto
In this paper, we give a causal solution to the problem of spline interpolation using H-infinity optimal approximation. Generally speaking, spline interpolation requires filtering…
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…
Signal Reconstruction via H-infinity Sampled-Data Control Theory: Beyond the Shannon Paradigm
Yutaka Yamamoto, Masaaki Nagahara, Pramod P. Khargonekar
This paper presents a new method for signal reconstruction by leveraging sampled-data control theory. We formulate the signal reconstruction problem in terms of an analog performan…
Min-Max Design of FIR Digital Filters by Semidefinite Programming
Masaaki Nagahara
In this article we consider two problems: FIR (Finite Impulse Response) approximation of IIR (Infinite Impulse Response) filters and inverse FIR filtering of FIR or IIR filters. By…
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…
H-Infinity-Optimal Fractional Delay Filters
Masaaki Nagahara, Yutaka Yamamoto
Fractional delay filters are digital filters to delay discrete-time signals by a fraction of the sampling period. Since the delay is fractional, the intersample behavior of the ori…
Frequency Domain Min-Max Optimization of Noise-Shaping Delta-Sigma Modulators
Masaaki Nagahara, Yutaka Yamamoto
This paper proposes a min-max design of noise-shaping delta-sigma modulators. We first characterize the all stabilizing loop-filters for a linearized modulator model. By this chara…
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…
Optimal Discretization of Analog Filters via Sampled-Data H-infinity Control Theory
Masaaki Nagahara, Yutaka Yamamoto
In this article, we propose optimal discretization of analog filters (or controllers) based on the theory of sampled-data H-infinity control. We formulate the discretization proble…
L1-Optimal Splines for Outlier Rejection
Masaaki Nagahara, Clyde F. Martin
In this article, we consider control theoretic splines with L1 optimization for rejecting outliers in data. Control theoretic splines are either interpolating or smoothing splines,…
Packetized Predictive Control for Rate-Limited Networks via Sparse Representation
Masaaki Nagahara, Daniel E. Quevedo, Jan Ostergaard
We study a networked control architecture for linear time-invariant plants in which an unreliable data-rate limited network is placed between the controller and the plant input. Th…
Maximum-Hands-Off Control and L1 Optimality
Masaaki Nagahara, Daniel E. Quevedo, Dragan Nesic
In this article, 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 much shorter support than the hori…
Sparse Packetized Predictive Control for Networked Control over Erasure Channels
Masaaki Nagahara, Daniel E. Quevedo, Jan Ostergaard
We study feedback control over erasure channels with packet-dropouts. To achieve robustness with respect to packet-dropouts, the controller transmits data packets containing plant…