Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q19/00—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic
  • H01Q19/06—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using refracting or diffracting devices, e.g. lens
  • H01Q19/062—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using refracting or diffracting devices, e.g. lens for focusing
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q15/00—Devices for reflection, refraction, diffraction or polarisation of waves radiated from an antenna, e.g. quasi-optical devices
  • H01Q15/0006—Devices acting selectively as reflecting surface, as diffracting or as refracting device, e.g. frequency filtering or angular spatial filtering devices
  • H01Q15/0013—Devices acting selectively as reflecting surface, as diffracting or as refracting device, e.g. frequency filtering or angular spatial filtering devices said selective devices working as frequency-selective reflecting surfaces, e.g. FSS, dichroic plates, surfaces being partly transmissive and reflective
  • H01Q15/0046—Theoretical analysis and design methods of such selective devices
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q7/00—Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop

Definitions

• This invention refers to receiving and transmitting of electromagnetic radiation devices technique and, in particular, to broadband receiving and transmitting antennas of high (20 - 40db) gain in centimeter and decimeter band and in a longer wave length (1-10m or longer) and of small dimensions (1-2cm).
• the invention is intended for designing of an electronic device to be used as the multichannel television antenna for receiving and transmission of the television signal on Earth and in space in industrial, military and private television installations and in mobile phone systems as well.
• the use of this antenna in all these installations will provide the increase of density of the stream of information received or transmitted, as the frequency range of transmitted or received signals is expanded from audio into video range.
• contemporary digital signal processing proposed antenna provides mobile phone devices with ability to transmit or receive as audio and video information as well.
• antenna parameters may be realized only if antenna is made of nonlinear dielectric material with very high dielectric permeability, which is highly dependant of intensity of the incident electric field, which characteristic frequency of switching of polarization for low level of said electric field at normal ambient temperature is very high.
• Alternative polarization of this dielectric produces secondary electromagnetic field.
• Modern television transmitting antenna comprises a vibrator, which converts energy of high frequency oscillations of vibrator conductor free charges into energy of the electromagnetic field radiated into surrounding space. Conversion is based on alternate electric current being the source of electromagnetic field.
• Antenna while receiving, serves reverse function, h. e. converts energy of incident electromagnetic field into energy of oscillations of free electric charges in antenna vibrator.
• Said vibrators may be of two types: electric dipole and magnetic dipole.
• modern antennas design is based on the theory of radiation of infinitesimal electric or magnetic vibrator.
• Electric vibrator is called infinitesimal, when its length is many times less than transmitted wave length, and the phase and the amplitude of said wave is the same along all vibrator length.
• Magnetic vibrator comprises conductor turn with diameter many times less than the transmitted wave length.
• To receive television signals antennas designed in accordance with these physics laws, are used. Television signals are received by straight dipole, antenna Udo-Yagi etc. Television antennas, both transmitting and receiving, usually operate in meter and decimeter bands.
• Transmitting antennas are usually designed as systems of straight dipoles; gain (AG) and antenna directivity (AD) depends on the layout and the way dipoles are fed. If antenna support cross-section dimensions are small enough and AG needed does not exceed 4-5, then a turnstile dipole is usually used. In all other cases they are using panel type antennas, assembled of separate panels, comprising dipoles and auxiliary parts, which are mounted around the support, in accordance with AD desired, evenly or not and radiate in phase or with some phase shift. Usual dimensions of television dipole system antennas are about 1m and they are installed at the great height to provide normal signal in the coverage zone.
• the basic material of antenna construction is metal, for dipole material must be of high conductivity, as in a dipole electric current must circulate to produce electromagnetic field.
• dielectric antenna comprises of dielectric rode, in which electromagnetic field is excited by metallic waveguide or by coaxial line central electrode.
• the special type wave (so called "surface wave"), running along the rode axis, is excited and as a result tangent components of electric and magnetic field on the surface of the rode are brought about.
• Phases of said components vary by the law of traveling wave.
• dielectric antenna is the traveling wave antenna, comprising of infinitesimal electric and magnetic vibrators. Its maximum of radiation, as in every traveling wave antenna, coincides with rode axis. AD of dielectric antenna depends on phase velocity of surface wave.
• Dielectric antenna rode is made of low loss dielectrics, h. e. with small electromagnetic waves attenuation.
• Dielectric antennas are employed mainly in airborne radio apparatus of centimeter and decimeter band.
• materials of high magnetic permeability are used.
• Such antennas are called ferrite or magnetic.
• the high magnetic permeability makes possible to produce ferrite antennas with the dimensions substantially smaller than that of common (without core) loop antenna with the same EMF induced in it.
• Magnetic antenna comprises of the loop antenna (multi turn usually) with the magnetic core.
• Said core is usually made of magnetodielectric or ferrite.
• Magnetic antennas are applied mainly for radio direction finding, radio navigation and especially wide they are used in portable radiosets. They have the same AD as that of common loop antennas.
• Magnetic antenna loop is usually connected to variable capacitor to form at the input of radioset a parallel resonant tank, tunable to the wavelength needed. While transmitting, in the magnetic antenna core the electromagnetic field of high intensity is excited.
• the magnetic antenna core is solid or assembled of separate sections if its dimensions are too big. Installing the core into the loop (made of conductor) increases its EMF in N times, impedance of radiation in N 2 times and loop's inductance in about N times.
• N depends on effective magnetic permeability of the core, which in it's turn depends on core's initial magnetic permeability and it's length/radius ratio, on core's radius and the radius of the loop. Magnetic moments of domains are summing up and the intensity of the magnetic field, induced in the core, becomes higher, than that of the incident wave.
• Precisely such an antenna (magnetic one), providing good characteristics (both while transmitting or receiving) even with low level current signals may be employed in cellular communications. But there are wavelength limitations for these antennas. The wavelength of the received signal might exceed the characteristic size of the dielectric antenna but to some extent only. The effective wavelength in magnetic antenna core becomes less than that of the incident wave in several tens of times only.
• the area of antenna's cross-section is many tens of times less, than that of area of incident radiation and, therefore, the received signal energy is less to the same extent.
• Insertion of the core into the loop, along with the positive effect of increasing EMF, causes the increase of heat losses, brought on by conductive currents and hysteresis losses. Losses, as a rule, are bigger for high magnetic permeability materials and are increasing with the shortening of the wavelength of the signal received.
• the use in television antenna construction dielectric and magnetic materials of high dielectric and magnetic permeability allows to minimize their characteristic dimensions to tens of centimeters, if all other initial output parameters are maintained.
• dielectrics of high magnetic permeability there are nonlinear dielectrics of very high dielectric permeability. And in these nonlinear mediums dielectric permeability is dependant on external electric field intensity, operation frequency and temperature. Such dielectrics are called nonlinear. In such a medium there are domains of dipoles too but electric ones. Under the influence of external electric field electric domains align along the field direction and produce on the surface of these dielectrics surface charges, which in its turn produce secondary electric field of intensity exceeding the field, which it caused. Inside the dielectric the resulting field is of zero value, as electric fields of positive charges of domains combines with that of negative charges.
• dielectric antennas mainly dielectric medium to influence the phase velocity and to form AD was used.
• the increase of dielectric permeability causes the increase of refraction index of this medium.
• This property was used for designing such antennas, as lens antenna, horn antenna and dielectric antenna. In last one this property of the medium was used to transform the long wave into shorter one, h. e. enabling the small antenna to receive the long wave signals.
• Such antennas may be used in cellular communications. In cellular communications decimeter band is mainly employed.
• nonlinear dielectrics with high permeability and its dependence on external electric field intensity, operation frequency and temperature to minimize antenna's dimensions to 1cm may be used.
• the materials of such properties are usually called segnetoelectrics or antisegnetoelectrics.
• Segnetoelectrics are polarized even at the absence of external electric field. This is spontaneous polarization, which is caused by segnetoelectric crystal structure modification. Segnetoelectrics differ from common dielectrics in that their spontaneous polarization direction may be changed into the reverse one by weak external electric field.
• segnetoelectrics with one polarization axis segnetosalt
• several polarization axes barium titanate
• Crystal state, in which segnetoelectric is spontaneously polarized, is called polar phase (segneto phase). Crystal state without polarization is called nonpolar phase.
• the temperature of transfer of nonpolar phase into polar one or the other way round is called dielectric Curie point.
• Dielectric permeability of segnetoelectrics in segneto phase is abnormally high.
• Non polar segnetoelectric polarization is directly proportional to the electric field intensity and in segnetophase it depends on it nonlinearly. Segnetoelectrics spontaneously divide into areas, called electric domains.
• Such entrapped electrons or holes may change their position because of heat fluctuations. As this takes place, total electric moment of the unity of dielectric volume equals to zero. If the external electric field is applied, such movements are directed mainly along the field direction. Thus in dielectric volume electric dipole torque is induced, h. e. polarization takes place.
• the relaxation time of this type of polarization at the room temperature is about 10 "2 - 10 "9 c. Such time of relaxation is matched by operating frequency about hundreds of GHz, quite fit into the frequency band of antenna, in transmitting or receiving mode.
• Segnetoelectric antenna comprises vibrator quite similar of common modern electric dipole antenna. It differs only in that in common antenna alternate current of free electric charges is induced by external alternate electric field, when in segnetoelectric antenna the incident electric field induces polarization of vibrator material, thus generating alternate electric field of bonded charges of polarized dielectric, h. e.
• Such composite antenna possess, besides great dielectric permeability, big magnetic permeability too, which leads to very strong reduction of traveling wave length.
• This antenna consists of many segnetoelectric vibrators. Their overall area is selected so, as AG of segnetoelectric antenna matched that of parabolic television antenna of 1 m diameter.
• big magnetic permeability provides for the greater increase of EMF in metallic loop, when alternate current of free charges is induced. This metallic loop goes through all the segnetoelectric vibrators so that rotary magnetic field encloses it and induces alternate current of free charges.
• H 01 Q 19/09, 1998) comprising inducing of high frequency current in metallic vibrator core by external electromagnetic field, excitation in cylinder volume of segnetoceramics in segnetophase surface charges of polarization, inducing in surrounding space, while transmitting, and excitation in said cylinder volume, while receiving, secondary electromagnetic field for precise tuning and retuning of antenna to other frequency ranges by way of interaction of electromagnetic wave and nonlinear dielectric mediums.
• Antenna is made of composite material, which shortens the wave, traveling in its volume. Principally new is ceramic nanocomposite material , in which the wave is shortened. It comprises a multitude of dipole cells, which are have micro and nano dimensions.
• antennas can be envisioned as compressed springs, with the energy stored, which are capable to react at tiniest changes of electromagnetic radiation.
• resonance properties of antenna comprising of cylinder volume of segnetoceramics with control electrodes, connected to a constant voltage source, are used. Under the influence of electric field of said source, dipoles in segnetoceramic align along the direction of the field applied and, when influenced by external high frequency electromagnetic signal, produce high frequency polarization, which, in its turn, induce high frequency currents of polarization of said cylinder volume and said currents are sources of secondary high frequency electric field.
• This design allows decreasing dimensions of parabolic antennas, receiving signals from satellites in tens of times.
• Applied dielectric composite materials really posses unique physical features. Manufacturing of antennas for TV reception in meter and decimeter bands is organized already.
• the development of this antenna has been carried out in the project "New generation antennas of composite materials of special electro physic properties, small size, for different purposes".
• the project was aimed to create principally new type of antenna, which mass and dimensions will be many times less, than that of traditional ones.
• the basis of this development serves the usage of composite materials with special electrophysical properties.
• New method of transmitting and receiving of electromagnetic waves is based on phenomena of shortening of electromagnetic wave inside the composite material and using of said material in design of active elements of antennas.
• Antenna is a "tablet” measuring 6.5 cm of diameter and 2.8 cm of thickness. It is designed to receive signals of all TV channels of meter and decimeter band (ch 1-69).
• This antenna being many times smaller than common "big” ones, is as good as they in quality of the signal reception. Characteristic features of this antenna are reduction of dimensions in 10-20 times, reducing of internal noise of antenna, as compared with the common ones, possibility to operate with a reflector, pollution-free design, universal application, possibility of covered installation. Besides it is not sensitive to many sources of interference and it is possible to use it in radio broadcasting. In this patent application on the design of segnetoelectric antenna already known method is visible.
• the thickness of the disc may be small enough, for example, not exceeding 0.1 mm but not less than 10 mkm. It is possible to assemble plenty of such discs to enhance the power of the signal received. This design matches electric dipole antenna with the resistor in the turn and additional electric signal.
• the signal received in antenna is taken of the vibrator, comprising of metal rode, inserted in the hole in the center of cylinder body segnetoceramic antenna.
• high frequency currents are induced by external electromagnetic field and by electric field, induced by external electromagnetic field because of polarization by constant voltage source.
• This antenna gain is provided because of segnetoceramic cylinder volume serves as a horn, focusing high frequency electric field in the vicinity of the vibrator.
• This antenna may be represented as a circuit, comprising of capacitor, in which surface charges arise, which in its turn induce free charges in control electrodes material, vibrator resistance, antenna characteristic resistance and the constant voltage source.
• the necessary antenna dimensions may be achieved only if dielectric material with high dielectric permeability, depending on external electric field intensity, for example, segnetoelectric. Its dielectric acceptability factor must be of maximum at the room temperature. This dielectric must operate at the high frequencies of alternate electric field.
• the plate of segnetoelectric should be cut out of segnetoelectric monocrystall with the cutting plane perpendicular to maximal dielectric permeability direction or a layer of polycrystal mixture of segnetoelectric should be applied on the surface of another material with common dielectric permeability. On butt ends of said plates control electrodes are clad, but electrodes thickness should exceed the "scin-effect" layer on the frequency received thickness.
• the device is assembled of segnetoelectric plates into a package.
• the area of the plate and its number is defined of necessary antenna gain.
• the radio signal is taken from the metallic wire turn, going through the holes in all the segnetoelectric plates. It is possible to achieve big gain, wide operational frequency band in transmitting and receiving mode, good antenna directivity and improvement of other parameters by others, already existing, ways and means. Most often it is done by increasing the antenna dimensions. Applying in design of modern antennas such materials, as segnetoelectrics, allow the reduction of antennas dimensions but not a significant one.
• the method of exciting of the segnetoelectric antenna comprising inducing of high frequency current in a vibrator metallic core by means of an external electromagnetic field exciting of surface charges of polarization in a cylinder volume of segnetoceramic in the segneto state inducing in surrounding space, while transmitting, and in said cylinder volume, while receiving, secondary electromagnetic field for the precise tuning or for the frequency change differing in that the cylinder volume of antenna is made up of interleaved layers of cegnetoceramic plates and plates of ferrodielectric material, which fill up cylinder volume and which are stiffened into a layer package, where each segnetoceramic layer serves as a vibrator, and for amplification of radio signal, while receiving, excite the antenna by inducing surface charges of polarization in each segnetophase vibrator by external electromagnetic field of layered package and by same polarization charges excite secondary electromagnetic field by way of inductive coupling of vibrator package with afore said core induce high frequency currents in said core made as metallic loop
• segnetoelectric antenna comprising of cylinder volume of segnetoceramics, central metallic electrode, formed as a rode, mesh control electrodes on butt planes of cylinder volume and external constant voltage source differing in that antenna cylinder volume is made up of segnetoceramic plates, which thickness is not less than 10 mkm, divided by ferrodielectric plates of same thickness, while all plates are hermetically stiffened into unified layered package of segnetoceramic vibrators, flat butts of which are clad with control electrode layers with thickness not more than 0,1 mkm, all of which are connected in parallel and a core is made of metallic wire turn and is rigidly mounted into the vibrators package hole and its leads are connected to receiver-transmitter device.
• Vibrators are assembled as a capacitor connected to a constant voltage source, while on exterior sides of capacitor plates piezoelectric plates are tightly fixed.
• Vibrator control electrodes are made of semiconductor material of p- or n-type.
• Vibrators are made of semiconductor material of p- or n-type and its control electrodes are made of semiconductor material of opposite type with junctions of n-p-n or p-n-p type. The essence of the innovation is explained by drawings, figures and plots. The process of incident wave scattering on the segnetoelectric plate is shown on fig.1.
• Fig.5 displays antenna design (a), cross-section of a part of an antenna comprising plates of dielectric and of ferrite with the core (b) and equivalent electric schematic of an antenna (c).
• the device to effect the method proposed comprise cylinder volume 1 of segnetoceramics plates 2, which thickness is not less than 10mkm, divided by ferrite plates 3 of same thickness, while all plates are hermetically stiffened into unified layered package 4 of segnetoceramic vibrators 5, flat butts of which are clad with control electrode layers 6 with thickness not more than 0,1 mkm, while all vibrators are connected by this electrodes in parallel, and a core 7 is made of metallic turn and is rigidly mounted into the vibrators package central hole 8 and it's leads are connected to receiver-transmitter device 9.
• Vibrators 5 are assembled as a capacitor connected to a constant voltage source 10, while on exterior sides of capacitor plates piezoelectric plates 2 are tightly fixed.
• Vibrator control electrodes 6 are made of semiconductor material of p- or n-type.
• Vibrators 5 are made of semiconductor material of p- or n-type and its control electrodes are made of semiconductor material of opposite type with junctions of n-p-n or p-n-p type.
• the cylinder volume of antenna 1 is made up of interleaved layers of segnetoceramic plates 2 and plates of ferrodielectric material 3 , which fill up cylinder volume and which are stiffened into a layer package 4, where each segnetoceramic layer serves as a vibrator 5, and for amplification of a radio signal, while receiving, excite the antenna by inducing surface charges of polarization 11 in each segnetophase vibrator by external electromagnetic field 12 of layered package 4, and by the same polarization charges 11 excite secondary electromagnetic field 13 by way of inductive coupling of vibrator package with afore said core 7 induce high frequency currents in core, made as metallic loop and thus increasing amplification factor of a signal received in accordance with the number of vibrators 5 in layered package 4, vibrator 5 area, segnetoceramic's permeability, ferrodielectric plates 3 magnetic permeability, the inductance of segnetoceramic vibrators package 4, package 4 characteristic impedance, the number of turns
• Nonlinear dielectrics are capable to polarize in external electromagnetic field, generating in the process of polarization secondary electromagnetic field. Naturally, electric polarization occurs when dipoles are aligned. Bonded surface charges generate in the process the external electric field.
• Segnetoelectrics may generate electrostatic field, external and internal as well.
• the intensity of electric field generated by surface charges of segnetoelectric in segnetophase.
• P Curie point
• Dielectric permittivity of segnetoelectrics in weak fields depends on their frequency too. With the increase of the frequency, permittivity may decrease in the frequency range, where it is near the resonance frequency of segnetoelectric plate with given dimensions. When the field frequency passes the resonant one upwards, the crystal passes from mechanically free condition into mechanically fixed one.
• the decrease of permittivity occurs at rather low frequencies (tens of MHz depending on geometry of plates).
• the next region of decrease of polarization of segnetoelectrics is caused with inertness of domains. For barium titanate it lies in decimeter and centimeter bandwidth.
• H d - ⁇ ⁇ S ⁇ -l ⁇ E ⁇ Sf -Mi ⁇ S ⁇ - ⁇ JtfS j ', i i i i ⁇ j
• the first component is similar to permittivity, found empirically by Barret.
• the second is similar to already known Langeven function.
• the dope segnetoelectrics permittivity may be now defined as
• the nonlinearity of dielectric properties in the region of phase transition temperatures was measured.
• the value of nonlinear factor ⁇ of shift of phase transition temperature T c (Curie point) and variations of dielectric permeability ⁇ under the influence of electric field was determined.
• the segnetoelectric crystals with Curie temperature about 290 -300K were mainly considered.
• Test specimens were grown by Chokhralsky method and were formed as plates of several tenth of mm thickness with main plane (100).
• Dielectric permeability was measured in the frequency range from 10kHz up to 100MHz. It is known, that segnetoelectric crystal polarization by electric field E strongly affects dielectric permeability ⁇ anomaly in the phase transition region.
• the electric field intensity £ varies with variations of coming radio signal.
• resonant curves (for different values of temperature and external electric field intensity) of the first harmonic of the current of oscillatory tank with segnetoelectric (BaTiO 3 ) capacitor will change with the increase of temperature and points of resonance will move to lesser frequencies.
• Such tendency also arises with the increase of external field at the fixed temperature in small fields region, where resonance points shift to lesser frequencies takes place too. If coming signal amplitude increases, said shift is slowed down.
• the last case may be explained by dependence of dielectric permeability of segnetoelectric on temperature and applied field.
• E(r, ⁇ ) E 0 (r, ⁇ )+i- ⁇ - ⁇ 0 -![- ⁇ - ⁇ 1 (r, ⁇ )+ ⁇ 1 (r, ⁇ )] E(r, ⁇ ) G(r-r J ) d 3 r
• G(r) exp(i k ⁇ r ⁇ ) /4 ⁇ ⁇ r ⁇ -
• Green function k l ⁇ 0 ⁇ 0 ⁇ ) - wave number of phone medium.
• Eo(r, ⁇ ) - defines intensity of incident wave, while integer in the right side of equation, represents scattered by nonlinear nonuniformities field. Equation is represented in scalar way and it is known as Lippman- Schwinger equation.
• Z( ⁇ ) - — — l— - — — — — arsh( — ) complex input 4 ⁇ ⁇ Q A ⁇ 2 ⁇ impedance, depending on the object dimensions.
• the real part Z( ⁇ ) coincides with the radiation impedance of electric dipole with the accuracy to constant factor, while the imaginary part corresponds with the imaginary part of input impedance of radiating systems. When L «a, this imaginary part corresponds with inductive resistance of disc.
• This equation corresponds with equivalent schematic from Fig.2. This representation is used while analyzing the response of the vibrator, loaded on nonlinear contact or diode. Unlike the traditional method, this equation is derived by asymptotic analysis of precise wave representation.
• nonlinear medium properties are considered in this equation by current l( ⁇ ) and capacity C( ⁇ ).
• the external electrodynamic problem consists of defining that scattered field.
• Scattered by segnetoelectric plate field for a distant zone (when
• »1) may be determined by formula Ei( ⁇ ,r) ⁇ - i- ⁇ - ⁇ 0 l ⁇ ( ⁇ )-L-G(r- r 0 ,) Where l ⁇ ( ⁇ ) l( ⁇ ) - i-C( ⁇ ) u( ⁇ ).
• the scattered field may be determined by formula for elementary electric dipole: E ⁇ ( ⁇ ,r) ⁇ - ⁇ - ⁇ o l ⁇ ( ⁇ )-L-G(r- r 0 ,)-sin( ⁇ ),
• spectral characteristic of induced in segnetoelectric electromagnetic field is determined and in the first approximation it is obtained, that the real part of this expression determines the spectral characteristic of the field in medium and the imaginary part characterizes the attenuation of induced in segnetoelectric electromagnetic wave.
• the curves of dependency of scattered field intensity on frequency at given parameters of medium are shown on Fig.3
• the ordinate of the plot is the intensity of electric field in mV/m, while the abscissa is the frequency of alternate electric field.
• the value of the current, induced by rotary magnetic field, generated by alternate electric field of polarization of segnetoelectric volume of investigated antenna will be about 0.1 A. This value many times exceeds currents of modern antennas.
• Fig.4 there are shown: 1 - force lines of electric field of the incident wave, 2 - segnetoelectric plate, 3 - force lines of induced electric field, 4 - force lines of rotary magnetic field (H-i) of the secondary.electromagnetic wave (E-i), induced by alternate electric field, 5 - surface electric charges (P), excited by electric field of incident electromagnetic wave, 6.- controlling electrodes 7 - the conductive turn in the central hole of segnetoelectric disc.
• Fig.4 displays physical processes of inducing by rotary magnetic field, generated by alternate electric field of polarization, caused by surface charges of polarization, caused by scattered incident electromagnetic wave, of alternate current in a conductive turn.
• the design of a television antenna may be represented as segnetoelectric (BaTiO 3 ) disc with control electrodes on the butt end, which are connected to a voltage source. Inside the segnetoelectric electric field intensity is equal to zero Electrically this antenna represents a capacitor, where on the surface of dielectric bonded surface charges are generated by electric field of incident electromagnetic wave. This charges induce in capacitor plates (control electrodes) free charges. The plates are connected via resistance of segnetoelectric.
• Output signal comprises signals of all discs.
• Discs number is determined by necessary antenna gain (AG).
• AG antenna gain
• the wavelength changes of a electromagnetic wave threading the segnetoelectric of antenna depend on its parameters and design.
• the presented design corresponds with magnetic dipole antenna with the resistor in a turn and additional electric signal, generated by surface charges of segnetoelectric.
• Another design of an antenna is possible. In that case ohm resistance of a turn is very small but wave impedance is high.
• Antenna is made of thin segnetoelectric disc with small (10mkm -0.1 mm) hole in the center, strung on a conductive core (turn), interleaved by similar discs of simple non polarized dielectric or of ferrodielectric of high permeability (barium ferrite).
• the combination of segnetoelectric with ferrite strongly affects the electromagnetic wave, transforming it.
• Regular nonuniformity of a medium causes the traveling wave effect along the antenna axis.
• One or many turns of metal wire are put through the central hole of discs.
• the transformation of bonded surface charges into free charges in a conductor causes, in accordance with Faraday law, alternate electric current in a metal turn. This current represents an input signal, brought by incident wave.
• the signal amplitude depends on (besides incident wave field intensity) number of segnetoelectric discs and their area. Electrically it may be represented as an external energy source inductively coupled (pos.17) with the central core winding (pos.18 Fig.5B).
• the AG of a parabolic dish equals 40db.
• the AG of segnetoelectric antenna of the first design, comprising one disc, equals 20db. Therefore, to even AG of two antennas, we should take 100 segnetoelectric discs. When comparing the areas of these two antennas, we see, that to even them by area 300 discs of 30cm 2 each are necessary. But such a quantity is excessive, as far as AG is concerned.
• the overall antenna length equals 3mm, that is far less than that of the first design antenna.
• the AG of last design segnetoelectric antenna is quite comparable with that of parabolic dish for meter bandwidth.
• the last design antenna complies with all demands to TV antennas of meter bandwidth.

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