Study of propagation characteristics of very low latitude whistlers by means of three-dimensional ray-tracing computations

1997 ◽  
Vol 102 (A4) ◽  
pp. 7537-7546 ◽  
Author(s):  
Kenji Ohta ◽  
Yasuhiro Nishimura ◽  
Tomomi Kitagawa ◽  
Masashi Hayakawa
Keyword(s):  
Ray Tracing ◽  
Three Dimensional ◽  
Propagation Characteristics ◽  
Low Latitude

Propagation characteristics of very low latitude whistlers by ray tracing

1993 ◽  
Vol 76 (7) ◽  
pp. 63-69
Author(s):  
Kenji Ohta ◽  
Tooru Tomomatsu ◽  
Osamu Takahashi ◽  
Masashi Hayakawa
Keyword(s):  
Ray Tracing ◽  
Propagation Characteristics ◽  
Low Latitude

Assessment of troposphere mapping functions using three-dimensional ray-tracing

GPS Solutions ◽  
2013 ◽  
Vol 18 (3) ◽  
pp. 345-354 ◽  
Author(s):  
Landon Urquhart ◽  
Felipe G. Nievinski ◽  
Marcelo C. Santos
Keyword(s):  
Ray Tracing ◽  
Three Dimensional ◽  
Mapping Functions

Methods to Accelerate Ray Tracing in the Monte Carlo Method for Surface-to-Surface Radiation Transport

2006 ◽  
Vol 128 (9) ◽  
pp. 945-952 ◽  
Author(s):  
Sandip Mazumder
Keyword(s):  
Monte Carlo ◽  
Ray Tracing ◽  
Radiation Transport ◽  
Three Dimensional ◽  
Intersection Point ◽  
Surface Radiation ◽  
Computational Domain ◽  
Two Dimensional ◽  
Spatial Partitioning ◽  
The Monte Carlo Method

Two different algorithms to accelerate ray tracing in surface-to-surface radiation Monte Carlo calculations are investigated. The first algorithm is the well-known binary spatial partitioning (BSP) algorithm, which recursively bisects the computational domain into a set of hierarchically linked boxes that are then made use of to narrow down the number of ray-surface intersection calculations. The second algorithm is the volume-by-volume advancement (VVA) algorithm. This algorithm is new and employs the volumetric mesh to advance the ray through the computational domain until a legitimate intersection point is found. The algorithms are tested for two classical problems, namely an open box, and a box in a box, in both two-dimensional (2D) and three-dimensional (3D) geometries with various mesh sizes. Both algorithms are found to result in orders of magnitude gains in computational efficiency over direct calculations that do not employ any acceleration strategy. For three-dimensional geometries, the VVA algorithm is found to be clearly superior to BSP, particularly for cases with obstructions within the computational domain. For two-dimensional geometries, the VVA algorithm is found to be superior to the BSP algorithm only when obstructions are present and are densely packed.

Acoustical Design Study on Application of Absorption Materials

2014 ◽  
Vol 711 ◽  
pp. 546-549
Author(s):  
Wei Lin ◽  
Wei Hwa Chiang
Keyword(s):  
Computer Simulation ◽  
Energy Distribution ◽  
Ray Tracing ◽  
Impulse Response ◽  
Background Noise ◽  
Three Dimensional ◽  
Design Phase ◽  
Design Study ◽  
Sound Energy ◽  
Reinforcement System

Taipei Top Church Auditorium is a hall primarily intended for praise and worship. A three dimensional ray tracing computer simulation was used to provide sound energy distribution on the audience area of the hall, realistic design have been performed. The volume of the hall is 24600m3, which is occupied for 2200 people and equipped the hall with acoustical curtains by modifying its acoustical characteristics. Objective measurements of impulse response are reported, and background noise control and noise isolation are also be considered in the design phase. Reinforcement system is conducted to meet all the activity for the acoustical environments.

scholarly journals Analysis of Propagation Characteristics for Various Subway Tunnel Scenarios at 28 GHz

2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Chengjian Wang ◽  
Wenli Ji ◽  
Guoxin Zheng ◽  
Asad Saleem
Keyword(s):  
Ray Tracing ◽  
Root Mean Square ◽  
Millimeter Wave ◽  
Measurement Data ◽  
Path Loss ◽  
Small Scale ◽  
Delay Spread ◽  
Mean Square ◽  
Propagation Characteristics ◽  
Subway Tunnels

In order to meet the higher data transmission rate requirements of subway communication services, the millimeter wave (mmWave) broadband communication is considered as a potential solution in 5G technology. Based on the channel measurement data in subway tunnels, this paper uses ray-tracing (RT) simulation to predict the propagation characteristics of the 28 GHz millimeter wave frequency band in different tunnel scenarios. A large number of simulations based on ray-tracing software have been carried out for tunnel models with different bending radiuses and different slopes, and we further compared the simulation results with the real time measurement data of various subway tunnels. The large-scale and small-scale propagation characteristics of the channel, such as path loss (PL), root mean square delay spread (RMS-DS), and angle spread (AS), for different tunnel scenarios are analyzed, and it was found that the tunnel with a greater slope causes larger path loss and root mean square delay spread. Furthermore, in the curved tunnel, the angle spread of the azimuth angle is larger than that in a straight tunnel. The proposed results can provide a reference for the design of future 5G communication systems in subway tunnels.

Sign in / Sign up

Export Citation Format

Share Document