Сборник текстов на казахском, русском, английском языках для формирования навыков по видам речевой деятельности обучающихся уровней среднего образования

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  The propagation, reflection, and transmission of plane waves, and the analysis and design of multilayer films.
  

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  Waveguiding systems, including metallic, dielectric, and surface
  

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  Linear and aperture antennas, scalar and vector diffraction theory, plane-wave spectrum, Fourier optics, superdirectivity and superresolution concepts, antenna array design, numerical methods in antennas, and coupled antennas.
  

The text emphasizes connections to other subjects. For example, the mathematical techniques for analyzing wave propagation in multilayer structures, multisegment transmission lines, and the design of multilayer optical filters are the same as those used in DSP, such as the lattice structures of linear prediction, the analysis and synthesis of speech, and geophysical signal processing. Similarly, antenna array design is related to the problem of spectral analysis of sinusoids and to digital filter design, and Butler beams are equivalent to the FFT.

Electromagnetic radiation (EM radiation or EMR) is the radiant energy released by certain electromagneticprocesses. Visible light is an electromagnetic radiation. Other familiar electromagnetic radiations are invisible to the human eye, such as radio waves, infrared light and X-rays.

Classically, electromagnetic radiation consists of electromagnetic waves, which are synchronizedoscillations of electric and magnetic fields that propagate at the speed of light through a vacuum. The oscillations of the two fields are perpendicular to each other and perpendicular to the direction of energy andwave propagation, forming a transverse wave. Electromagnetic waves can be characterized by either thefrequency or wavelength of their oscillations to form the electromagnetic spectrum, which includes, in order of increasing frequency and decreasing wavelength: radio waves, microwaves, infrared radiation, visible light,ultraviolet radiation, X-rays and gamma rays.

In the quantum theory of electromagnetism, EMR consists of photons, the elementary particles responsible for all electromagnetic interactions. Quantum effects provide additional sources of EMR, such as the transition of electrons to lower energy levels in an atom and black-body radiation. The energy of an individual photon is quantized and is greater for photons of higher frequency. This relationship is given by Planck's equation E = hν, where E is the energy per photon, ν is the frequency of the photon, and h isPlanck's constant. A single gamma ray photon, for example, might carry ~100,000 times the energy of a single photon of visible light.

Geometrical optics, or ray optics, describes light propagation in terms of rays. The ray in geometric optics is an abstraction, or instrument, useful in approximating the paths along which light propagates in certain classes of circumstances.

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  propagate in rectilinear paths as they travel in a homogeneous medium
  
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  bend, and in particular circumstances may split in two, at the interface between two dissimilar media
  

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  follow curved paths in a medium in which the refractive index changes
  
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  may be absorbed or reflected.
  

Geometrical optics does not account for certain optical effects such as diffraction and interference. This simplification is useful in practice; it is an excellent approximation when the wavelength is small compared to the size of structures with which the light interacts. The techniques are particularly useful in describing geometrical aspects of imaging, including optical aberrations.

A slit that is wider than a single wave will produce interference-like effects downstream from the slit. It is easier to understand by thinking of the slit not as a long slit, but as a number of point sources spaced evenly across the width of the slit. This can be seen in Figure 2 .

The variation in wave intensity can be mathematically modeled. From the center of the slit, the diffracting waves propagate radially. The angle of the minimum intensity (θ_min) can be related to wavelength (λ) and the slit's width (d) such that:

dsin⁡θmin=λ.
The intensity (I) of waves at any angle can also be calculated as a relation to slit width, wavelength and intensity of the original waves before passing through the slit:

I(θ)=I0(sin⁡(πx)πx)2,

dλsin⁡θ.