We have realized a fiber fuse terminator consisting of a commercially available short length of step-index multimode fiber, spliced with conventional SMFs. The fabricated fiber fuse terminator suppressed the fiber fuse propagation when the input power was 6 W, at a wavelength of 1.55 μm.

In this paper, we present a bathroom monitoring sensor system using a 79GHz ultra-wideband radar sensor. It offers low privacy and anti-humidity capability unlike imaging sensors and IR sensors. It is designed to detect various dangerous states such as falling and drowning with Hidden Markov Model (HMM). We conducted experiments in order to show the effectiveness which is also compared with a conventional scheme. It has been found that our proposed scheme is more accurate than the conventional method.

We propose a new method to combine the Knn algorithm with the neural network. Due to the size of the training set affects the accuracy of the training results, we propose a neural network with selective training set. Its main method is changed the size of the training set by a control variable to get the most suitable training data. The advantage of this method is that the training set can be adjusted to achieve a trade-off between the positioning accuracy and the training set size. The result of Knn algorithm positioning is more accurate by adding BP (Back Propagation) selective neural network algorithm.

The use of ultra-high frequency radio frequency identification (RFID) technology has recently been studied for the wireless management of consumable parts in automobiles. The RFID tag antennas attached to the consumable parts in an engine room, which is a closed metal space, require horizontal polarization and omnidirectional radiation characteristics. This paper presents the design results of a circular folded dipole antenna for an RFID tag on a metallic cylinder.

A reflectarray with upper sidelobe level (SLL) suppression is proposed for the fifth generation (5G) wireless communications in this letter. A unit cell of the reflectarray is composed of a crossed-dipole element to realize dual-polarized operation. In order to validate the improvement of upper SLL, a 45 degree-beam-steering reflectarray, comprising 20×10 elements, operating at 28GHz for quasi-millimeter-wave applications is designed and analyzed numerically. Simulation results demonstrate that the worst value of all upper SLL in radiation pattern of the reflectarray is reduced by about 10dB as compared to that in previous design.

Two-dimensional communication (2DC) textile is a technical combination of e-textile and two-dimensional signal transmission (2DST) technology. 2DC textile-based wearable system has several benefits, whereas designing a transmission scheme that ensures both power and high data rate transfer among numerous distributed devices on the textile is still challenging work. This paper proposes a charge/communication switching approach based on a baseband transmission system without modulation/demodulation of carriers. Successful power and more than 1 Mbps, half-duplex data transfer between one master and ten slaves was achieved. We also explain the trade-off relationship between the charging power, data rate, and device number by applying this approach.

Multi-user MIMO and spatial diversity are attractive techniques to improve the link capacity. In this paper, multi-user zero-forcing (ZF) coordinated with user-wise maximal-ratio transmitting and combining (MRTC) diversity is studied. A closed-form expression for the received signal-to-noise ratios (SNRs) achievable with 2-user ZF coordinated with user-wise MRTC diversity is derived for the given MIMO channel condition. It is shown from the derived SNR expression that the uplink capacity is higher than the downlink capacity and that the uplink capacity is not necessarily the same among users while the downlink SNR is always identical for users. This is confirmed by numerical evaluation assuming a Rayleigh fading environment.

We investigated a two-frequency secondary radar system to prevent traffic accidents between pedestrians and vehicles at intersections with poor visibility. We measured a ranging property between a vehicle and a pedestrian, and direction detecting property. This paper shows the results of these experiments measured in a large anechoic chamber with a wooden L-shaped wall to emulate an NLOS condition. A measurement error in NLOS was larger than that in LOS. However, it was able to detect a pedestrian in NLOS and the direction of the one.

The analysis method using the chain parameter matrix (F-matrix) has been proposed for calculating radiated emission from the cable used by power line communication (PLC). In this paper, the radiation resistance was implemented to the F-matrix as the load of the common mode current which was converted from the differential mode PLC signal by the unbalance of the transmission system and was considered as the emission source. The calculated result for the simple cable model was compared to the measurement value and to the calculation value of which the radiation resistance was not considered. The investigation result indicated that the influence of radiation resistance appeared at the frequency where the high radiated emission was observed.

Millimeter-wave (mmW) wireless body area network (WBAN) is effective in reducing inter-WBAN interference because of the large attenuation by human body blocking. In this paper, for evaluating the interference power and the channel capacity of mmW WBAN in consideration of the regularity of the arrangement of users, we proposed a user arrangement model which is assumed an actual overcrowded train. In the proposed model, the channel capacity was calculated in consideration of the user’s shape, arrangement, and direction in the train. As a result of the computer simulation with the proposed model, it is concluded that the channel capacity of the overcrowded train environment with regularity in user arrangement varies more than that of a random environment.