Modeling and Measurements of Scattering from Road Surfaces at Millimeter-Wave Frequencies

نویسندگان

  • Kamal Sarabandi
  • Eric S. Li
چکیده

Millimeter-wave radar-based sensors are being considered for a number of automotive applications including obstacle detection and collision warning, true-speed, and road-surface recognition. In this paper, the interaction of electromagnetic waves with asphalt road surfaces, possibly covered with ice or water, at millimeter-wave frequencies is studied. First, an experimental procedure for determining the effective dielectric constant of bituminous mixtures used in road-surface constructions is developed. In this procedure, the effective dielectric constant is derived using a simple inverse-scattering algorithm to the measured radar cross sections of cylindrical specimen of a standard asphalt mixture. Then the vector radiative transfer equation is used to formulate the scattering from a multilayer medium representing an iceor water-covered asphalt surface. The University of Michigan polarimetric 94-GHz radar system was deployed for characterizing the polarimetric backscatter responses of asphalt surfaces under many physical conditions near grazing incidence angles (70 –88 ). The measured backscatter coefficients and parameters of copolarized phase difference statistics of a dry asphalt surface with smooth interface at one incidence angle were used to derive the phase and extinction matrices of the asphalt medium. The experimentally determined phase and extinction matrices are substituted in the radiative transfer formulation to predict the scattering from asphalt surfaces under all conditions. Excellent agreement between theoretical predictions and measured quantities is obtained.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Low Grazing Incidence Millimeter-Wave Scattering Models and Measurements for Various Road Surfaces

Systematic characterization of the scattering behavior of traffic targets, clutter, and their associated interactions are required in order to design and assess the performance of millimeter-wave-based sensors for automated highway system (AHS) applications. In this paper, the polarimetric radar backscatter response of various road surfaces is investigated both theoretically and experimentally....

متن کامل

Electromagnetic Scattering from Dielectric Surfaces at Millimeter Wave and Terahertz Frequencies

With the demand for larger bandwidths and faster data speeds, wireless communication systems are expanding into the millimeter wave and terahertz region of the electromagnetic spectrum. Successful transition to higher frequencies, particularly for systems located in urban or indoor environments, will require a thorough understanding of the reflection, transmission, absorption, and scattering of...

متن کامل

Polarimetric Characterization of Debris and Faults in the Highway Environment at Millimeter-Wave Frequencies

In this paper, measurements and models for the polarimetric backscatter response of various point targets on roads and road surface faults is presented. Of particular interest are debris and faults that could lead to fatal accidents and damage of property. A desired safety feature for automotive radar sensors is the capability of detecting such debris and faults. The detectability of a point ta...

متن کامل

Gallium Phosphide IMPATT Sources for Millimeter-Wave Applications

The potentiality of millimter-wave (mm-wave) double-drift region (DDR) impact avalanche transit time (IMPATT) diodes based on a wide bandgap (WBG) semiconductor material, Gallium Phosphide (GaP) has been explored in this paper. A non-sinusoidal voltage excited (NSVE) large-signal simulation method has been used to study the DC and high frequency characteristics of DDR GaP IMPATTs dsigned to ope...

متن کامل

Sea Surfaces Scattering by Multi-Order Small-Slope Approximation: a Monte-Carlo and Analytical Comparison

L-band electromagnetic scattering from two-dimensional random rough sea surfaces are calculated by first- and second-order Small-Slope Approximation (SSA1, 2) methods. Both analytical and numerical computations are utilized to calculate incoherent normalized radar cross-section (NRCS) in mono- and bi-static cases. For evaluating inverse Fourier transform, inverse fast Fourier transform (IFFT) i...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 1998