Kazuma Tomimoto’s research while affiliated with Saga University and other places

... In actual measurements, fast measurements are necessary because propagation conditions may change within 12 minutes. Therefore, the authors proposed a measurement method using a rotating reflector antenna to realize fast DOA measurements using a large aperture antenna [9]. The rotating reflector antenna is an antenna in which the primary radiator remains fixed and the reflector rotates independently. ...

Reference:

Improvement of Angular Dependence of Angular Profile in DOA Measurement Method using Rotating Reflector Antenna

... According to the research mentioned, it has the advantage of increasing the efficiency of the gain in energy harvesting, but there are also disadvantages in terms of gain optimization and much complexity with more adjusting points. As a result, the researchers choose disadvantages identified by this research that is the first part of a basic dipole antenna structure [27,28] with an increasing I-shaped stub to widen the frequency [16,[29][30][31][32] and gain enhancement for the antenna by using the horn waveguide [33][34][35] and in terms of getting more energy. The second part studies the matching impedance circuit using a Radial Stub Circuit (RSC) [20,36,37] with the power frequency signal converter circuit by using a full-wave rectifier circuit with a voltage multiplier circuit [16,38,39] to increase the pressure on the rectenna system that is designed to receive power at a frequency of 510-790 MHz, which is the digital TV wireless transmission system. ...

Reference:

DIPOLE ANTENNA WITH HORN WAVEGUIDE FOR ENERGY HARVESTING IN DTV SYSTEMS

... Direction of arrival (DOA) estimation has been an extensivelyinvestigated topic of signal processing with applications in various areas of social life, such as sensing networks, public safety and military fields [1][2][3]. The exploration of DOA has been expanded under different conditions, such as non-circular signals [4], two-dimensional L-shaped arrays [5], sparse nested array with extended aperture and mutual coupling [6] and phase offset correction [7]. ...

Reference:

Weighted sparse Bayesian method for direction of arrival estimation based on grid fission

... In recent years, antennas and radio propagation technologies have been developed to enhance V2V communications. The propagation loss characteristics and an antenna configuration suitable for V2V application have been studied [5]. The evaluation of a model for a cognitive V2V communication system with two active user cooperation revealed that, as the power from the primary user increased, the V2V user failed to achieve the standard bit error rate (BER) requirement [6]. ...

Reference:

A Performance Study of Mobility Speed Effects on Vehicle Following Control via V2V MIMO Communications

... Recently, a wide variety of radar and sensor systems have been developed. In these systems for mobile communications such as the V2V direct communications [1,2], the high functionality and compactness are required. The monopulse method with simple configuration is a useful technology to be applied to the tracking antennas for the communications. ...

Reference:

Basic Study of a Monopulse DOA Estimation Circularly Polarized Array Antenna Integrated with Magic-Ts

... Similarly, the measurement and modeling of vehicular wireless channels provide an important theoretical basis for research on vehicular communication technology. Many scholars have shown that the parameters of V2V channels, such as the root-mean-square delay spread [13], power delay profile (PDP) [14], and Doppler power spectrum [15], vary with time. Moreover, due to the random high-speed movement of the receiving and transmitting antennas in wireless vehicle communication and the existence of many high-speed moving scatters in the communication environment [16], the vehicle wireless channel presents obvious non-stationary characteristics. ...

Reference:

Analysis of Non-Stationarity for 5.9 GHz Channel in Multiple Vehicle-to-Vehicle Scenarios

... Yen [4] formed a circular passive synthetic array using a single array element. Paper [5] introduced an AOA measurement method using turntable, vector receiver, horn antenna and synthetic aperture processing. ...

Reference:

Research on Monopulse Angle Measurement Algorithm in Pseudolite Local Positioning System