IEICE Communications Express
Online ISSN : 2187-0136
ISSN-L : 2187-0136
Advance online publication
Showing 1-34 articles out of 34 articles from Advance online publication
  • Kouichi Genda, Mitsuru Abe, Shohei Kamamura
    Subject Area: Network
    Article ID: 2020XBL0123
    Published: 2020
    [Advance publication] Released: September 24, 2020
    JOURNALS FREE ACCESS ADVANCE PUBLICATION

    This paper proposes a backbone network resource optimization algorithm for video communications of teleconferencing that use edge computing. In the current video communication architecture, the key component, the multi-point control unit (MCU), is deployed in the central cloud server, and its bandwidth consumption in the backbone network becomes huge as the video resolution and the frequency of use increase. By using edge computing, MCU can be deployed at the entrance node of the backbone network. This can reduce the bandwidth consumption of the backbone network. However, the edge deployment and routing (EDR) problem, which is classified as NP-hard, should be solved to achieve sufficient bandwidth reduction. To solve the EDR problem within a feasible time, we propose a divide and merge algorithm using the linear programming approach. We demonstrate that, with our algorithm, bandwidth consumption using edge computing is reduced by approximately 30% compared to the current architecture on a world-wide network.

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  • Tatsuya Nagao, Takahiro Hayashi, Yoshiaki Amano
    Subject Area: Wireless Communication Technologies
    Article ID: 2020XBL0115
    Published: 2020
    [Advance publication] Released: September 04, 2020
    JOURNALS FREE ACCESS ADVANCE PUBLICATION

    In order to improve the efficiency of spectrum use, systems that share spectrum while avoiding interference between different systems are being investigated. In the millimeter-wave band, which is expected to be utilized in the future, the received power fluctuates due to quasi-static obstructions such as people and vehicles, but such temporal variations have not been taken into account in conventional methods. In this paper, we use a variety of machine learning algorithms for comparative evaluation to forecast the temporal fluctuations of radio propagation due to changes in the number of people and vehicles in order to achieve more dynamic spectrum access.

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  • Tetsuya Iye, Kensuke Tsuda, Akihiro Tanibayashi, Yoshimi Fujii
    Subject Area: Antennas and Propagation
    Article ID: 2020XBL0104
    Published: 2020
    [Advance publication] Released: August 31, 2020
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    This paper reports the error effects of actual mmWave RF devices on beam pattern by monte carlo simulation. A mmWave beamforming by array antenna is one of the most promising technique to realize access methods which meet requirements of URLLC, mMTC, and eMBB communication simultaneously. The accuracy of analog beam forming is necessary to be increased to realize 5G or beyond 5G access. Our simulation shows individual effects of frequency, phase, and gain non-linearity characteristics on beamforming accuracy. We conclude that a proper calibration on the phase difference between array antenna elements improve the beamforming accuracy effectively and guarantee providing sufficient beam gain required in the entire communication area.

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  • Ryuya Hayashi, Shusuke Narieda, Hiroshi Naruse
    Subject Area: Wireless Communication Technologies
    Article ID: 2020XBL0112
    Published: 2020
    [Advance publication] Released: August 27, 2020
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    This letter presents a multiple antenna based spectrum sensing via a sequential detection technique. A log-likelihood ratio test of a low computational complexity statistic is defined and we develop the sequential detection based spectrum sensing using the test. The presented technique can reduce the computational complexity by overlapping samples for the calculation of each statistic while almost maintaining the accuracy of signal detection. Numerical examples are shown to validate the effectiveness of the presented technique.

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  • Rei Furukawa, Nobuaki Kubo, Ahmed El-Mowafy
    Subject Area: Navigation, Guidance and Control Systems
    Article ID: 2020XBL0096
    Published: 2020
    [Advance publication] Released: August 21, 2020
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    The reflections and diffractions of global navigation satellite system (GNSS) signals from buildings may produce large measurement errors. Detecting non-line-of-sight signals using 3D maps is a means to detect and exclude satellites with large measurement errors. However, the true position is typically needed for using 3D maps. In this study, we verify the assumption that an approximate user position can be used when using 3D maps. We found that the correct fixed position of real-time kinematic GNSS (RTK-GNSS) could be achieved when approximate positions for RTK-GNSS assisted by 3D maps were within 5-15 m from the true position.

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  • Jung Suk Joo
    Subject Area: Wireless Communication Technologies
    Article ID: 2020XBL0102
    Published: 2020
    [Advance publication] Released: August 21, 2020
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    Selected mapping (SLM) is one of the most widely used peak-to-average power ratio (PAPR) reduction schemes-it selects and transmits a signal having the smallest PAPR among candidate signals by performing a full search (FS). In this Letter, a simple modification to reduce the computational complexity of SLM-based PAPR schemes is proposed that terminates searching process when it meets a candidate signal not causing a clipping, instead of having the smallest PAPR.

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  • Kohei Takizawa, Kohei Fujiwara, Yuta Watanabe, Ryuichi Kobayashi, Sato ...
    Subject Area: Antennas and Propagation
    Article ID: 2020COL0024
    Published: 2020
    [Advance publication] Released: August 20, 2020
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    In general, a millimeter-wave component, such as a waveguide, is made of metal, therefore, it is heavy weight and expensive. In this development, a W-band waveguide based on an additive manufacturing with an electroless plating was demonstrated. We confirmed that the performance of the transmission is approximately -2 dB in 75—110 GHz on a 50 mm long WR-10 waveguide.

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  • Koshiro Kitao, Tetsuro Imai, Minoru Inomata, Satoshi Suyama, Yusuhiro ...
    Subject Area: Antennas and Propagation
    Article ID: 2020COL0033
    Published: 2020
    [Advance publication] Released: August 20, 2020
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    We propose a correction formula using the percentage of area occupied by buildings, α, for a path model in the urban macrocell environment defined in ITU-R M.2135 based on measurements performed in Japan for below 6 GHz for 5G. Based on analysis, the regression results of the correction formula in which S, the median of the difference between the measured path loss and that of the reference path model is proportional to α, is better than when S is proportional to the logarithm of α.

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  • Aditya Rakhmadi, Kazuyuki Saito
    Subject Area: Electromagnetic Compatibility (EMC)
    Article ID: 2020XBL0098
    Published: 2020
    [Advance publication] Released: August 20, 2020
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    Tissue-mimicking phantom is a biological tissue replacement which has been used as a replacement to understand the relationship between the electromagnetic and the human body. However, many of the developed phantoms are produced for several MHz to several GHz region, and less in the kHz region. This research introduces a new phantom to understand the electromagnetic effect at kHz region. The phantom is a 500 kHz phantom which mimics human muscle dielectric properties. The dielectric properties of the phantom are adjusted by aluminum powder content, which is 40% of the total phantoms content. In this research, we use different phantom dielectric properties measurement method compared to the one at higher frequencies. Furthermore, the phantom thermal properties and density are measured to be used in numerical calculations.

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  • Takase Oshima, Hiroshi Hirayama
    Article ID: 2020XBL0105
    Published: 2020
    [Advance publication] Released: August 20, 2020
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    A folded dipole antenna with a class-F load, acting as a receiving antenna for microwave wireless power transfer, is proposed. Conventionally, a class-F load circuit and matching circuit are connected to a rectifier circuit. A capacitor is used to adjust the impedance for harmonic waves. The proposed antenna involves both the class-F load and matching circuit functions to decrease loss in the circuit and reduce space usage. The antenna design was optimized and demonstrated to verify the class-F function.

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  • Akio Ikami, Takahiro Hayashi, Yoshiaki Amano
    Subject Area: Wireless Communication Technologies
    Article ID: 2020XBL0106
    Published: 2020
    [Advance publication] Released: August 14, 2020
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    For the efficient use of frequency resources, dynamic spectrum allocation (DSA) between different radio systems is promising. In DSA, our approach is to allow different mobile network operators to use the same shared channel without the inter base station (BS) interference. However, this approach is computationally very expensive. Therefore, we formulate this reuse channel allocation as a 0-1 mixed-integer linier programming problem and propose an algorithm to improve the satisfaction of each BS and the time and frequency continuities, which can be used to solve the problem in practical time. Our evaluation demonstrates that our proposed algorithm can improve the satisfaction with the time and frequency continuities simultaneously.

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  • Kazuya Inoue, Koichi Ichige, Tatsuya Nagao, Takahiro Hayashi
    Subject Area: Antennas and Propagation
    Article ID: 2020XBL0100
    Published: 2020
    [Advance publication] Released: August 13, 2020
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    In this paper, we propose a radio propagation prediction method using machine learning and building occupancy estimation. There have been learning-based researches using aerial photographs and building occupancy images as spatial information. However, the availability of building occupancy images are often limited to urban areas. We assume the situation that only the aerial photographs are available, and aim to improve radio propagation prediction accuracy by estimating building occupancy images from the given aerial photographs.

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  • Taiki Tanemura, Wataru Chujo
    Subject Area: Wireless Communication Technologies
    Article ID: 2020COL0023
    Published: 2020
    [Advance publication] Released: August 06, 2020
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    In rolling-shutter (RS) optical camera communication (OCC), as the ratio of the exposure time to the symbol length increases, it becomes difficult to achieve error-free transmission due to inter-symbol interference. In this study, to increase the symbol rate, symbol decision based on spatial luminance distribution is adapted for RS OCC. When the symbol rate increases and the ratio is close to 1, it is difficult to achieve error-free transmission by conventional symbol decision based on pixel value. However, even when the ratio increases up to 1, error-free transmission is achieved by the symbol decision based on spatial luminance distribution.

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  • Shotaro Mishina, Mutsumi Suganuma, Wataru Kameyama
    Subject Area: Multimedia Systems for Communications
    Article ID: 2020COL0035
    Published: 2020
    [Advance publication] Released: August 06, 2020
    JOURNALS FREE ACCESS ADVANCE PUBLICATION

    In this paper, we investigate to estimate the subjective video quality of mobile users in a real situation of daily life. We conduct an experiment to collect bio-signals and sensor data from three subjects for a week as well as their contexts by questionnaire, and machine learning algorithms including Random Forest and k-Nearest Neighbor are applied for the estimation. The experimental results show that the subjective video quality is estimated accurately by Random Forest, while the contribution of users’ context is not confirmed. It suggests that the subjective video quality can be well estimated by bio-signals and sensor data of mobile users in a real situation.

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  • Kosuke Toda, Naomi Kuze, Toshimitsu Ushio
    Subject Area: Network
    Article ID: 2020COL0012
    Published: 2020
    [Advance publication] Released: August 04, 2020
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    Blockchain is a distributed ledger technology for recording transactions. To guarantee the immutability of the blocks, miners need a lot of computational resources for creating blocks (mining). Since mining is conducted distributedly by many miners, chain forks can occur in the blockchain. In this paper, we investigate the effects of miners’ locations, the size of the MP, and the network structure on the selection rate of blocks generated by the MP when chain forks occur through simulations.

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  • Yuki Hiroi, Wataru Kameyama
    Subject Area: Multimedia Systems for Communications
    Article ID: 2020COL0021
    Published: 2020
    [Advance publication] Released: August 04, 2020
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    “Person Re-identification” technology has attracted more attention because of the proliferation of surveillance cameras and the increased awareness of crime prevention. However, there are various problems. One of them is that the same person is likely to be recognized erroneously as a different person due to the differences in persons’ appearance. Therefore, in this paper, we propose a method of hard positive mining to achieve better performance in identifying the same person images that are difficult to identify as the same person. The evaluation results using MARS dataset show that the CMS by applying the proposed hard positive mining is higher than the existing method of CNN with temporal pooling. It suggests that it is effective to apply hard positive mining in MARS dataset.

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  • Ryota Bingo, Hiroyuki Yomo
    Subject Area: Wireless Communication Technologies
    Article ID: 2020COL0038
    Published: 2020
    [Advance publication] Released: August 04, 2020
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    This letter proposes a rate control for robust data transmissions utilizing multiple access points (APs) combined with packet-level forward error correction (FEC). Beacon frames received from multiple APs are used to select an appropriate set of PHY and FEC rates to be employed for uplink transmissions, which is based on a machine-learning technique. With computer simulations, we show that the proposed rate control achieves the required reliability while significantly reducing the occupancy period of the shared channel.

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  • Tomoya Tanaka, Tomio Kamada, Chikara Ohta
    Subject Area: Network
    Article ID: 2020COL0040
    Published: 2020
    [Advance publication] Released: August 04, 2020
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    The importance of real-time and data-driven notification has been growing for social services and Intelligent Transporting System (ITS). As an advanced version of Pub/Sub systems, publish-process-subscribe systems with MEC (Multi-access Edge Computing), where published messages are spooled and processed on edge servers, have been proposed. In this paper, we present a topic-based publish-process-subscribe system that allows a topic to be managed on multiple edge servers so that messages are processed near publishers and transferred to subscribers immediately. However, managing each topic on numerous edge servers can cause exhaustion of storage resources on edge servers. We introduce a simple topic allocation method on edge servers to discuss the problem. Experiments show the feasibility of our proposed system.

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  • Kyo Minoguchi, Toshiaki Shitaba, Tomoaki Yoshida, Jun Terada
    Subject Area: Transmission Systems and Transmission Equipment for Communications
    Article ID: 2020XBL0094
    Published: 2020
    [Advance publication] Released: August 04, 2020
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    We develop the first OLT-pluggable extended-loss-budget transceiver necessary for 10G/1G compatible PON with N:1 redundant OLT protection. This paper newly define the requirement of the OLT transceiver supporting protection by assuming an additional loss of redundant function. The average output power of 6.95/8.35 dBm and minimum receiver sensitivity of -32.02/-34.53 dBm for 10G/1G are attained, respectively. Experiments also confirm 40-km-SMF transmission with no dispersion penalties. It achieves the 36.02/35.53-dB loss budget as 10G/1G OLT transceiver, where ONU transceiver’s specification is based on 10GBASE-PR40/1000BASE-PX40, successfully meeting required loss budget for N:1 redundant OLT protection.

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  • Takashi Ohira
    Subject Area: Transmission Systems and Transmission Equipment for Communications
    Article ID: 2020XBL0085
    Published: 2020
    [Advance publication] Released: July 31, 2020
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    This paper considers how a class-E amplifier behaves when the load deviates from its nominal impedance. The Kirchhoff’s law and Fourier series formulate the circuit into three simultaneous equations. These equations are decomposed into zeroth- and first-order terms to apply the perturbation technique. The zeroth-order solutions meet the zero-voltage and zero-current switching conditions. The first-order formulas express the DC current consumption, RF output amplitude and phase, equivalent output impedance, and periodic turn-on power dissipation in terms of the load resistance and reactance deviations.

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  • Mampei KASAI, Hidekazu MURATA, Toshiro NAKAHIRA, Koichi ISHIHARA, Taka ...
    Subject Area: Wireless Communication Technologies
    Article ID: 2020XBL0089
    Published: 2020
    [Advance publication] Released: July 31, 2020
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    Terminal-collaborated multiple-input multiple-output (MIMO) reception with adaptive terminal selection schemes has been studied experimentally. In the experimental system, frequency-domain iterative MIMO equalization was employed, and its performance was evaluated by making use of recorded signal waveforms in a measurement campaign. In iterative signal processing, it is known that early stopping can control unnecessary iterations. In this letter, it is revealed that early stopping can not only reduce computational complexity, but also improve the bit error ratio performance of iterative processing. This is because early stopping prevents the iteration process from causing errors.

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  • Kazuyuki Ishida, Satoshi Yoshima, Ayano Sakamoto, Takashi Suehiro, Mas ...
    Subject Area: Satellite Communications
    Article ID: 2020XBL0092
    Published: 2020
    [Advance publication] Released: July 31, 2020
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    The digital payload for next generation high throughput communication satellites is expected to reduce the operators’ CAPEX and OPEX. Photonic technologies, which have a great affinity with digital signals, have been studied in order to increase the data throughput and reduce the mass of the satellites. Here, we propose an optical time division multiplexing system for routing the signals in the digital channelizer and have conducted a feasibility study on the transmission efficiency. This system has the potential to reduce the cost, mass, and power consumption, and to improve reliability by cleaning up the switches used for routing the signals within the satellites.

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  • Nanami Tanizawa, Mutsumi Suganuma, Wataru Kameyama
    Subject Area: Multimedia Systems for Communications
    Article ID: 2020COL0026
    Published: 2020
    [Advance publication] Released: July 28, 2020
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    The purpose of this paper is to estimate emotions for music pieces with lyrics. We investigate whether four emotions (happy, sad, angry and relaxed) can be accurately estimated by obtained bio-signals of subjects during music listening by analyzing them with convolutional neural network. Questionnaire responses by subjects are used as the correct labels, and the four emotions are classified by each and combined. The results of the analysis show that the accuracies of the both classification methods highly exceed the chance level. It suggests the possibility of emotion estimation for music listeners by bio-signals.

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  • Takuma Watanabe, Hiroyoshi Yamada, Yasuyuki Oishi
    Subject Area: Sensing
    Article ID: 2020XBL0091
    Published: 2020
    [Advance publication] Released: July 27, 2020
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    In this letter, we present the first demonstration of spectral domain polarimetric decomposition concept with airborne circular synthetic aperture radar (CSAR) dataset. In the CSAR systems, radar-carrying aircraft moves along a circular path which encloses the desired target area. The CSAR image contains the scattering characteristics of the target with respect to the azimuth angle, and it can be retrieved via transforming the spatial domain image into its spectral domain representation. Furthermore, the application of polarimetric decomposition to the spectral domain CSAR image provides an additional information about the polarimetric scattering mechanisms. A publicly released airborne polarimetric CSAR dataset is used for the demonstration.

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  • Kazuyuki Ishida, Satoshi Yoshima, Ayano Sakamoto, Takashi Suehiro, Mas ...
    Subject Area: Sensing
    Article ID: 2020XBL0095
    Published: 2020
    [Advance publication] Released: July 27, 2020
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    Optical remote sensing has been greatly expanded by the construction of satellite constellations and improving the performance of the optical sensors. As the data throughput of earth observation satellites increases, photonic technology is expected to be used for the interconnections within the payload in order to reduce its overall size, mass, and power consumption, and to improve its immunity to EMI. Here, we propose an optical time division multiplexing technology for N+1 redundancy in the payload, which is able to improve reliability by reducing the number of active components in the satellites, and present a feasibility study on its transmission efficiency.

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  • Yasushi Yuminaka, Keigo Taya, Yosuke Iijima
    Subject Area: Transmission Systems and Transmission Equipment for Communications
    Article ID: 2020XBL0086
    Published: 2020
    [Advance publication] Released: July 14, 2020
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    Four-level pulse amplitude modulation (PAM-4) data formats are adopted to achieve next-generation high-speed data transmission standards. In this letter, a novel eye-opening monitoring technique based on machine learning is proposed to evaluate the received signal quality for the adaptive coefficients setting of a transmitter feed-forward equalizer for PAM-4 signaling. The monitoring technique employs a Gaussian mixture model (GMM) to classify the received PAM-4 symbols. Simulation and measured results of the coefficient adjustment using the GMM method are presented.

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  • Yasumasa Naka, Masaya Tamura
    Subject Area: Energy in Electronics Communications
    Article ID: 2020XBL0093
    Published: 2020
    [Advance publication] Released: July 10, 2020
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    Capacitive wireless power transfer is performed using large electrodes or using a medium having high relative permittivity such as water. The transfer efficiency demonstrates a pronounced change with frequency. A lumped-constant equivalent circuit with parasitic elements represents the change. However, a relationship between conditions for generating minimum/maximum values of the transfer efficiency and structural parameters of the electrodes in the coupler has not clarified. In this study, an equivalent circuit is proposed using a distributed-constant circuit. We converted the lumped-constant circuit into two open-ended directional couplers. From the result, we derived the conditions for generating the minimum and maximum values of the voltage input/output ratio. The efficiencies calculated by the distributed-constant circuit and electromagnetic simulation were in good agreement.

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  • Satoshi Yoshida, Kenjiro Nishikawa, Shigeo Kawasaki
    Subject Area: Wireless Communication Technologies
    Article ID: 2020COL0007
    Published: 2020
    [Advance publication] Released: July 09, 2020
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    In this letter, an initial verification results of a bandwidth tunable power amplifier in Ku-band designed by the hybrid semiconductor integrated circuit (HySIC) concept is reported. A GaAs monolithic microwave integrated circuit (MMIC) and a Si radio frequency integrated circuit (RFIC) were utilized as the HySIC configuration in the circuit design. For the purpose of initial confirmation of this design validity, the GaAs and Si chips were fabricated and packaged onto the copper tungsten plate with gold plating. As measured results, the lower cut-off frequency was changed from 9.8GHz to 11.9GHz, resulting in the bandwidth tunability in Ku-band.

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  • Yusuke Yano, Tohlu Matsushima, Osami Wada
    Subject Area: Electromagnetic Compatibility (EMC)
    Article ID: 2020COL0019
    Published: 2020
    [Advance publication] Released: July 09, 2020
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    Adverse effect of pulse disturbances on the communication quality is investigated experimentally on in-vehicle Ethernet (1000BASE-T1, IEEE 802.3bp). Common- and differential-mode pulse disturbances were injected into communication cables by a method referring to the coupling network described in IEC 62228-5. As a result, it was revealed that steep change of differential signal due to pulse disturbance degrades the communication quality at a specific pulse width.

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  • Koyo Tategami, Mitoshi Fujimoto, Koshiro Kitao, Minoru Inomata, Satosh ...
    Subject Area: Antennas and Propagation
    Article ID: 2020COL0008
    Published: 2020
    [Advance publication] Released: June 30, 2020
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    In the 5th generation mobile communication system, introduction of small cells using low-height base station is being examined. Small cells are installed in urban street cell environments where mobiles are densely populated. Therefore, actual measurement and complicated modeling of radio wave propagation are necessary to grasp the propagation characteristics. In this paper, a simple propagation delay estimation method is proposed. In the proposed method, neural network using urban area structure parameters is applied. It is shown that the propagation delay time can be easily estimated by the proposed method without considering moving objects and trees.

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  • Issei Watanabe, Kentaro Nishimori, Ryotaro Taniguchi, Tomoki Murakami
    Subject Area: Antennas and Propagation
    Article ID: 2020COL0011
    Published: 2020
    [Advance publication] Released: June 30, 2020
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    In future wireless communication systems, massive multiple-input multiple-output (MIMO) is attracting attention for improving transmission rate. However, there is an issue that a large scale of hardware is needed due to massive numbers of antennas, transmitters, receivers, A/D and D/A convertors in massive MIMO. In this study, we propose a method to realize a virtual massive array with only one receiver by changing the beam pattern and performing A/D conversion at high speed within one symbol. The basic performance and effectiveness of the proposed method is demonstrated via a computer simulation.

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  • Masanori Gocho, Shoichiro Kojima, Hiroyoshi Yamada
    Subject Area: Antennas and Propagation
    Article ID: 2020COL0013
    Published: 2020
    [Advance publication] Released: June 30, 2020
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    In this report, we show the critical condition of the slope angle between orbits in InSAR (interferometric synthetic aperture radar) analysis. InSAR analysis, where the phase difference between two SAR observation data is measured, has been used for terrain height monitoring, and ground deformation detection, for example. However, InSAR data observed from nonparallel orbits degrades the performance of analysis. In the case of repeat-pass InSAR using airborne SAR, it is difficult to realize sufficiently parallel orbits. The purpose of this report is to formulate the nonparallel component of repeat-pass InSAR using an airborne SAR system and clarify the limitation of its parallel assumption. Then, we show the critical slope angle for use in InSAR analysis.

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  • Masakatsu Ogawa, Hoyeon Choi
    Subject Area: Wireless Communication Technologies
    Article ID: 2020COL0001
    Published: 2020
    [Advance publication] Released: May 19, 2020
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    Demand for positioning services such as object tracking systems and navigation systems is increasing. The current Wi-Fi positioning system uses the algorithm using mainly the signal strength. However, the signal strength is susceptible to multipath propagation, thus the ranging error generally large. The IEEE802.11mc specifies the fine timing measurement (FTM) protocol based on round trip time (RTT). As of now, few commercial products support the FTM function. The objective of this letter is to evaluate the accuracy of the Wi-Fi FTM using the actual devices and to perform one-dimensional positioning by a simple algorithm. In the one-dimensional positioning, average positioning accuracy is 0.10 m in outdoor and 0.23 m in indoor.

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  • Yuta Takano, Toshihiko Nishimura, Takeo Ohgane, Yasutaka Ogawa, Junich ...
    Subject Area: Wireless Communication Technologies
    Article ID: 2020COL0002
    Published: 2020
    [Advance publication] Released: May 14, 2020
    JOURNALS FREE ACCESS ADVANCE PUBLICATION

    Multi-user MIMO systems enable high capacity transmission. A base station, however, needs accurate channel state information (CSI). In time-varying environments, the CSI may be outdated at the actual transmission time. One of the solutions to this issue is channel prediction. The authors have proposed the prediction method using FISTA, a compressive sensing technique, for OFDM systems in a millimeter-wave band. Unfortunately, in realistic multipath environments, the prediction performance of the proposed technique degrades. In this letter, we examine the prediction performance in wider OFDM systems. It will be shown that FISTA reveals excellent performance in a sufficiently wide band case.

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