Millimeter-wave Propagation Characteristics Research Articles

Modeling Capability and Effectiveness of Resin Laminated Coatings in Millimeter Wave Radar FDTD Analysis of Automobiles

Automobile millimeter-wave corner radars are mounted behind plastic bumpers, and it is known that bumper shape and color affect millimeter-wave propagation characteristics. Numerical simulation is an effective means of predicting these effects, but explicitly meshing the bumper coating is not practical in terms of modeling man-hours and computational load. We have verified that the Multi-layered Thin Sheet function, which equivalently models the structure of multi-layered coating layers, provides results equivalent to those obtained by explicitly representing multi-layered coating layers while reducing the computational load.

Simulation and Analysis of 45 GHz Millimeter-wave Propagation Characteristics in Living Room

In this paper, the characteristics of millimeter-wave propagation at 45 GHz in a living room are investigated based on simulation by the method of shooting and bounding ray tracing/image (SBR/IM). Path loss of co-polarization and crosspolarization is compared to verify the accuracy of simulation. The angle of arrival of different polarization is also revealed. Root mean square (RMS) delay spread of co-polarization and cross-polarization is studied. It is shown that the RMS delay of co-polarization is generally higher than that of cross-polarization in this environment. In addition, the influence of furniture on the propagation characteristics of radio waves in the line-of-sight (LOS) environment is discussed.

Centimeter and Millimeter-Wave Propagation Characteristics for Indoor Corridors: Results From Measurements and Models

Centimeter and Millimeter-Wave Propagation Characteristics for Indoor Corridors: Results From Measurements and Models

Simulation and Analysis of 37 GHz Millimeter Wave Propagation Characteristics in Indoor Office Environment

In this paper, the method of shooting and bounding ray tracing/image (SBR/IM) is used in the simulation of indoor office environment, with which the study on millimeter-wave propagation characteristics can be processed well. Through simulation parameters such as path loss, received power and root mean square (RMS) delay spread is obtained and analyzed. All the results of this paper could be used as a reference when setting the position of transmitter and selecting parameters in indoor office environments.

Research and Development of Millimeter Wave Technology

Abstract This paper introduces the concept of millimeter wave, analyzes the advantages and disadvantages and propagation characteristics of millimeter wave, and expounds the research status of millimeter wave ground communication and millimeter wave satellite communication. The military application of millimeter wave communication technology in electronic countermeasures is taken as an example. Finally, the outlook for millimeter wave communication technology will open up new application fields in the future and have broad development prospects.

Safeguarding Millimeter Wave Communications Against Randomly Located Eavesdroppers

Millimeter wave offers a sensible solution to the capacity crunch faced by 5G wireless communications. This paper comprehensively studies physical layer security in a multi-input single-output (MISO) millimeter wave system where multiple single-antenna eavesdroppers are randomly located. Concerning the specific propagation characteristics of millimeter wave, we investigate two secure transmission schemes, namely maximum ratio transmitting (MRT) beamforming and artificial noise (AN) beamforming. Specifically, we first derive closed-form expressions of the connection probability for both schemes. We then analyze the secrecy outage probability (SOP) in both non-colluding eavesdroppers and colluding eavesdroppers scenarios. Also, we maximize the secrecy throughput under a SOP constraint, and obtain optimal transmission parameters, especially the power allocation between AN and the information signal for AN beamforming. Numerical results are provided to verify our theoretical analysis. We observe that the density of eavesdroppers, the spatially resolvable paths of the destination and eavesdroppers all contribute to the secrecy performance and the parameter design of millimeter wave systems.

Secure Transmissions in Millimeter Wave Systems

Exploiting millimeter wave is an effective way to meet the data traffic demand in the 5G wireless communication system. In this paper, we study secure transmissions under slow fading channels with multipath propagation in millimeter wave systems. Concerning the new propagation characteristics of millimeter wave, we investigate three transmission schemes, namely, maximum ratio transmitting (MRT) beamforming, artificial noise (AN) beamforming, and partial MRT (PMRT) beamforming. We evaluate the secrecy performance by analyzing both the secrecy outage probability (SOP) and the secrecy throughput for each scheme. Particularly, for the AN scheme, we derive a closed-form expression for the optimal power allocation ratio of the information signal power to the total transmit power that minimizes the SOP, as well as obtain an explicit solution on the optimal transmission parameters that maximize the secrecy throughput. By comparing the secrecy performances achieved by different strategies, we demonstrate that the secrecy performance of the millimeter wave system is significantly influenced by the relationship between the legitimate user’s and the eavesdropper’s spatially resolvable paths, which is different from the wireless systems with statistically independent channel models. In the absence of the common path between the legitimate user and the eavesdropper, MRT beamforming is the best scheme. In the presence of common paths, AN beamforming and PMRT beamforming show their respective superiorities depending on the transmit power and the number of common paths. Numerical results are provided to verify our theoretical analysis.

Measurement-Based Propagation Channel Characteristics for Millimeter-Wave 5G Giga Communication Systems

This paper presents millimeter-wave (mmWave) propagation characteristics and channel model parameters including path loss, delay, and angular properties based on 28 GHz and 38 GHz field measurement data. We conducted measurement campaigns in both outdoor and indoor at the best potential hotspots. In particular, the model parameters are compared to sub-6 GHz parameters, and system design issues are considered for mmWave 5G Giga communications. For path loss modeling, we derived parameters for both the close-in free space model and the alpha–beta–gamma model. For multipath models, we extracted delay and angular dispersion characteristics including clustering results.

STUDY OF PARABOLIC EQUATION METHOD FOR MILLIMETER-WAVE ATTENUATION IN COMPLEX METEOROLOGICAL ENVIRONMENTS

The parabolic equation (PE) method for estimating propagation characteristics of millimeter wave, which takes into account of attenuation caused by complex meteorological environment, is proposed. The meteorological environment is treated as a mixture composed of hydrometeors and atmospheric gases. Effective permittivity of the mixture is considered in this paper. Based on the effective permittivity, the PE model for estimating propagation attenuation of millimeter wave is developed via modifying the refractive index. Finally, the model is employed to simulate the propagation characteristics of millimeter wave in complex geographical environments of irregular terrain and rough sea surface, and in complex meteorological environments of standard atmosphere, rain and fog.

Simulation and Analysis of Millimeter-Wave Propagation Characteristics in Complex Office Environment

The several gigabit rate and license-free spectrum resources of 7 GHz bandwidth can be provided by the 60 GHz short-range communication technology, therefore it becomes one of the most promising alternative technologies in the wireless communication. In this paper, the millimeter wave propagation characteristics in the complex office environment are studied by the SBR/Image method. Firstly, under the complex office environment, the propagation characteristics including received power, the arrival angle and the probability distribution of the arrival angle are studied without regard roughness and oxygen absorption loss. Then, the RMS delay spreads in 60 GHz, 2.4 GHz and 5 GHz wireless LAN signals are simulated and compared.

Modeling of Millimeter-Wave Propagation in Rain Based on Parabolic Equation Method

The parabolic equation (PE) method is proposed to model millimeter-wave propagation in rain medium. The rain medium is treated as an anisotropy mixture comprising of spherical and ellipsoidal raindrops with different sizes in atmosphere. Taking into account the effects of size, distribution, temperature, and shape of the raindrops on the dielectric property, we introduce an analytical formula for the effective permittivity of the rain medium. The PE model for estimating rain attenuation is developed via revising the refractive index by the effective permittivity. The values of specific rain attenuation predicted by the model agree well with those obtained by the ITU-R model, which verifies the accuracy of our method. Finally, the PE model is applied to simulate the propagation characteristics of millimeter wave in rain over irregular terrain.

Millimeter-Wave Propagation Characteristics and Localized Rain Effects in a Small-Scale University Campus Network in Tokyo

Millimeter-Wave Propagation Characteristics and Localized Rain Effects in a Small-Scale University Campus Network in Tokyo

Effects of layers of different dust particles on propagation characteristics of millimeter wave

In the present paper theoretical investigation has been carried out to evaluate the effect of layers of different shapes of dust particles (ellipsoidal and spheroidal) on the propagation of millimeter wave. For this purpose a length of communication link has been considered, which contains layers of dust particles blown to the height of the link due to dust storms. Further, each layer of dust particles has been assumed as a section of transmission line and entire link as number of transmission line sections in a cascade. Hence using the concept of transmission line the reflection coefficient, transmission coefficient and absorption loss have been calculated. It is found that propagation parameters depend on frequency and visibility. Brewster’s phenomenon is clearly observed by the system which is at around 75° of angle of incidence.

Research on Propagation Characteristics of Millimeter Wave in Tunnels

This paper analyzes the propagation characteristics of the millimeter wave in various circular section tunnels. The received power, path loss and delay spread are discussed in detail using the verified software of Wireless InSite. The investigated tunnel models with circular section include the long straight tunnel, the tunnel with train inside and the curved tunnels with different curvature. The simulated results are verified by the experimental value in the actual tunnel. Several valuable conclusions are obtained, which would offer theoretical and practical references for the millimeter wave communication in limited spaces.

Millimeter-wave propagation characteristics of ceramics/polymer photonic crystal

Millimeter-wave propagation characteristics of ceramics/polymer photonic crystal

A New Fabrication Process for Low-Loss Millimeter-Wave Transmission Lines on Silicon

The new type of coplanar waveguide for millimeter-wave transmission was fabricated on silicon by chemical mechanical polishing and selective electroplating processes based on silicon technology. The thick interconnections obtained using these processes have less conductor loss than the conventional interconnections, and the deep grooves on both sides of a signal line in this new waveguide reduce the dielectric loss caused by the high permittivity of the silicon substrate. The electro-optic sampling technique confirmed that the new waveguide has excellent millimeter-wave propagation characteristics, low effective permittivity and low attenuation, at frequencies up to 300 GHz. The new fabrication processes should be useful in combining millimeter-wave systems with ultralarge-scale integrated circuits on silicon.

Propagation Characteristics in a Transversely Magnetized 70 GHz Waveguide Containing a p-InSb Slab Carrying an Applied Current

It has been experimentally observed that the 70 GHz millimeter-wave propagation characteristics in a transversely magnetized waveguide loaded with a p-type InSb slab are markedly varied by applying a current considerably smaller than that used in the previous studies employing n-InSb. It is suggested that the shift of the slow-surface-wave resonant magnetic field in this waveguide is responsible for the observed variation.

A study of optically controlled millimeter‐wave propagation characteristics in a metallic rectangular waveguide loaded with double dielectric layers

AbstractThis article presents the theoretical analysis of a new optically controlled metallic waveguide structure loaded with double dielectric layers in H face. This structure shows higher optical sensitivity than that loaded with a homogeneous semiconductor dielectric layer. It can give an optically controlled phase shift greater than 4000 deg/cm and an optically controlled attenuation of more than 200 dB/cm.

Theory Of Optically Controlled Millimeter-wave Phase Shifters

In this paper we analyze the millimeter-wave propagation characteristics of a dielectric wavegaide containing a plasma-dominated region. Such a device presents a new method for controlfirrg millimeter-wave propagation in semiconductor waveguides via either optical or electronic means resulting in ultrafast switching and gating. We have calculated the phase shift and attenuation resulting from the presence of the plasma. Higher order modes, both TE and TM, as well as millimeter-wave frequency variation, are studied in both Si and GaAs dielectric wavegnides. We have also formulated a surface plasma model that is a good approximation to the more elaborate volume plasma model. Phase shifts are predicted to he as high as 1400°/cm for modes operating near cutoff. These modes suffer very little attenuation when the plasma region contains a sufficiently high carrier density.