Masayuki Kurosaki - IEEE Xplore Author Profile

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Self-interference cancellation is an important technology to achieve full-duplex communication. The self-interference (SI) signal in IEEE 802.11 networks can be suppressed using Joint Transmission (JT) with null beamforming. This method requires a weight matrix that is obtained from the Channel State Information (CSI). However, JT requires very tight synchronization between multiple access points ...Show More
In recent years, high-definition video content such as YouTube and Netflix has become an integral part of our lives, increasing the demand for wireless transmission of 4 K and 8 K images with high quality. Consequently, many technical papers have proposed systems for high-quality video transmission. However, most of these systems extend international standards, making implementation difficult. The...Show More
One of the limiting factors in long-distance communication with optical fiber is dispersion. Dispersion causes optical pulses to broaden as they travel through the fiber, leading to intersymbol interference that ultimately degrades the signal quality. To solve this problem, a dispersion compensator is usually applied after a certain distance to bring the broadened signal back to its original form....Show More
Rate adaptation algorithm has an important role in the Wi-Fi network. It ensures that the nodes transmit at a suitable transmission rate with minimum packet errors on the receiving side. However, there are cases when the existing algorithms fail to adapt to the changes in the communication environment. In this paper, we propose a rate adaptation algorithm using a Deep Q-network (DQN), in which the...Show More
Recently, the Wi-Fi human activity recognition (HAR) system has attracted attention, using channel state information (CSI). CSI is a characteristic that indicates the radio propagation environment from transmitter to receiver, indoor environment. Therefore, sensing technology that predicts the indoor environment by calculating backward from the CSI is being considered. We first analyzed CSI in the...Show More
Packet collision can degrade wireless network performance. The IEEE 802.11 Wireless Local Area Network (WLAN) uses the Clear Channel Assessment (CCA) mechanism to monitor channel availability to avoid interference of the presence signal. CCA successfully detects 802.11 signals if it obtains the packet preamble information or detects the threshold ambient power on the channel to determine the chann...Show More
In this paper, we propose multi-task learning (MTL) using a convolutional neural network (CNN) to simultaneously perform packet format detection and modulation classification of wireless LAN (WLAN) signals. Compared to single-task learning, the main advantage of this method is the high classification accuracy and rapid learning with a lightweight neural network model. These are achieved because of...Show More
This paper proposes a full-duplex wireless communication system applying cooperative multiple-input multiple-output (Co-MIMO). This proposal solves self-interference (SI) in full-duplex wireless communication systems by applying the block diagonalization used in multi-user MIMO (MU-MIMO). Therefore, there is no need for a radio frequency (RF) canceller, which has a large hardware size and is diffi...Show More
H.264/SVC is a widely used compression standard with a very high lossy compression rate. The completeness of the H.264/SVC bitstream is very crucial in achieving high quality video decompression. This is especially true in regard to the base layer which contains the important coding data. In this paper, we improve the quality of H.264/SVC video transmission by using the Space Time Block Code (STBC...Show More
This paper presents a hardware implementation of low latency and highly accurate time synchronization for Industrial WLAN systems. The design of our media access control (MAC) layer supports both asynchronous and synchronous multi- user transmission protocols. Low overhead Packet Division Multiple Access (PDMA) scheme is utilized for Multi-user Downlink transmission, while Frequency Division Multi...Show More
We demonstrate a self-interference (SI) cancellation in cooperative multiple-input multiple-output (Co-MIMO) for full-duplex (FD) wireless communication systems by applying the block diagonalization used in multi-user MIMO. The proposed method's implementation uses a field-programmable gate array (FPGA) and software-defined radio (SDR). In the experiment, a total of 33 [dB] SI can cancel with two ...Show More
In this paper, we propose self-interference (SI) cancellation in cooperative multiple-input multiple-output (Co-MIMO) for full-duplex (FD) wireless communication systems. This proposal solves SI by applying the block diagonalization used in multi-user MIMO. Therefore, there is no need for a radio frequency (RF) canceller, which has a large hardware (HW) size and is difficult to extend to MIMO. Fur...Show More
This paper proposes a full-duplex wireless communication system applying cooperative multiple-input multiple-output (Co-MIMO). This proposal solves self-interference (SI) in full-duplex wireless communication systems by applying the block diagonalization used in multi-user MIMO (MU-MIMO). Therefore, there is no need for a radio frequency (RF) canceller, which has a large hardware size and is diffi...Show More
In this paper, we propose a hardware development of a high accuracy Precision Time Protocol (PTP) on Software Defined Radio (SDR) for Industrial WLAN systems. To increase the throughput of the transmission system, we propose a low overhead 3-frames exchange PTP instead of 4-frames transmission as IEEE 1588 PTP protocol. Besides, our hardware-software co-design of the full SoC MAC-PHY can select th...Show More
The Markov chain based model by Bianchi for IEEE802.11 distributed controlled access is a highly accurate analytical tool for estimating the system throughput when a single Basic Service Set (BSS) network operates in isolation. However, with the increase of wireless LAN access points being deployed on the same area, an environment with multiple BSS interfering with each other has become the defaul...Show More
Wireless video transmission through multiple-input multiple-output (MIMO) channels has become more and more popular recently. In the superposition MIMO system which non-orthogonally multiplexes several signals in the power domain, the receiver performs non-linear detection to estimate the transmitted signals, which is called postcoding. This paper proposes a multistage postcoder which combines max...Show More
The demand for high-resolution wireless video transmission technology is expected to increase greatly as the video resolution increases, and as the Wi-Fi devices spread. Wireless transmission of high-resolution video requires high throughput, therefore it is necessary to use a multiple-input multiple-output (MIMO) system. In this paper, we propose an evaluation platform for video transmission meth...Show More
Recently, video distribution over wireless networks has become more common due to the spread of smart devices. This paper proposes an optimal power allocation algorithm for the transmission of layered video streams over point-to-point multiple-input multiple-output (MIMO) systems combined with superposition coding. The proposed power allocation scheme is derived from the maximization of the weight...Show More
With the spread of mobile devices, image and video transmission is in great demand. The use of multiuser multiple-input multiple-output (MU-MIMO) systems, where multiple data can be sent to multiple users, is highly expected. This paper proposes a novel power allocation scheme for MU-MIMO systems, which minimizes the variance of channel capacities of each spatial stream of all users to achieve use...Show More
In this paper, we propose a system that verifies and corrects the accuracy of symbol timing synchronization processing to determine reception time in Wi-Fi system. Time-of-flight (ToF) based Wi-Fi indoor mobile position estimation uses transmission and reception time stamp of radio waves between the mobile terminal targeted for estimation and fixed Wi-Fi receivers. However, it is known that the ac...Show More
Currently, Global Positioning System (GPS) is widely used as a representative position estimation system. However, GPS suffers from poor position estimation accuracy in an indoor environment. Moreover, time synchronization between devices needs to be performed for position estimation which is a resource intensive process. In previous studies, an asynchronous protocol (i.e., no synchronization requ...Show More
In this paper, we propose a design of asynchronous communication for an industrial wireless LAN system. In our design, MAC is synchronous multi-user round-robin transmission protocol. Low overhead Packet Division Multiple Access scheme is utilized for Multi-user Downlink transmission up to 80 MHz, while Frequency Division Multiple Access is employed for the uplink transmission. The designed of PHY...Show More
In this paper, we propose an industrial Wireless Local Area Network (iWLAN) system compatible with asynchronous communication for industrial robots (iRBs) control in factory automation (FA) environments. The design of our media access control layer is synchronous multi-user round-robin transmission protocol. Low overhead Packet Division Multiple Access (PDMA) scheme is utilized for Multi-user Down...Show More
We demonstrate a precision time protocol (PTP) used to synchronize clocks in industrial wireless local area network (iWLAN) communication systems. The implementation of the system on FPGA boards for accurate verification and to test the feasibility of the system in a real environment. The result has been confirmed that time synchronization is high accuracy from 40 to 100 ns.Show More
In recent years, wireless video streaming has become very popular due to the widespread of Wi-Fi terminals supporting multiple-input multiple-output (MIMO) techniques. High-quality video streaming in wireless networks is a challenging topic. This paper proposes a greedy power allocation algorithm (GPA) for video streaming by overloaded MIMO systems. The proposed GPA adaptively controls power distr...Show More