Electronic control beam turns the antenna into an active signal processing means. The most common form of such an antenna is a phased antenna lattice (headlights). Various ways of controlling electromagnetic waves in headlights, in particular control using semiconductor diodes, are considered.

Imagine a high-directed antenna, providing communication with the artificial satellite of the Earth (USS). Such an antenna has an outfoculated beam, accurately directed to the communication object. An example of such an antenna may be the ground antenna of the "Orbit" station, which was used in the first Soviet television transmission systems and ensuring multi-channel telephone communication through the USS. Such an antenna is a parabolic reflector with a diameter of about ten meters. In order to track the object of communication or radion surveillance with such an antenna, it is necessary to rotate the entire pretty heavy mechanical system.

Obviously, in many cases, the antenna needs, in which the direction of the beam would not be due to the orientation of the entire antenna as a mechanical structure. Need an antenna with the non-mechanical movement of the beam or, in other words, an antenna with electronic scanning. Under the scanning here it is understood as the movement of the ray of antenna, which reviews the space in a given spatial angle. Such an antenna is needed not only in communication systems with the ISS, but also in the motion control system in the Big Airport area. The special role of an antenna with electronic scanning was played and continued to play in systems of missile defense (Pro). Since the beginning of the 90s, an antenna with electronic scanning has become the object of attention of automotive companies. In this regard, such antennas can be the subject of mass demand, like a color TV or a personal computer. The technical solution of an antenna with electronic scanning is presented in the form of a lattice, in the nodes of which are the simplest emitters of the electromagnetic wave. The power circuit of these emitters is organized so that the radiation emitted by each emitter coherently with the radiation of all emitters, while the phase of the emitted waves varies on a given law. Changing the phase distribution on the emitters allows you to form a ray of antenna in a given direction. Such a lattice lattice with a controlled phase distribution of waves radiated by the elementary emitters received the name of the phased antenna lattice (headlights). Thus, the term antenna with non-mechanical movement of the beam, an antenna with electronic scanning or a phased antenna grid is practically synonymous.

The idea that the beam of the coherent emitter system can be controlled by changing the distribution of the phases on the emitters, was expressed for a long time. One of the first antennas with the non-mechanical control of the focus diagram was built for the transatlantic radiotelephone line in 1937. This antenna, possessing a rather high orientation, made it possible to change the direction of reception of rays in the vertical plane and in this way to choose the direction of the arrival of the rays, the least weakened when reflected from the ionosphere. Since, thanks to the directional properties of the antenna, only one reflected beam was taken, then the fading of the signal was dramatically decreased. This antenna was a rhombic antennas system located along a straight line on a plot of about 1.5 km long. The control of the orphanage diagram was carried out by changing phase relations between currents in separate diamonds. High speed control ray of the rhombic antenna system was not required. The radar development set the problem of controlling the antenna pattern during the time intervals measured at the beginning milliseconds, and then microseconds and even microsecond shares.

As far as can be judged by well-known publications, the first antenna with electronic scanning for use in radar was carried out in the Leningrad Electrotechnical Institute (LETI) in 1955 in the group under the guidance of prof. Yu.Y. Yurova (1914-1955). The principle of action of the antenna was based on the control of wave phases in several antenna emitters using phase studies containing ferrite elements. In those years, the electronics of different frequencies began the wide use of ferrite-iron-containing metal oxides, which are dielectrics, but have magnetic properties close to iron properties. The radar use of the antennas with electronic scanning was carried out in the United States. The first publication of a Ferrite-based phase student, intended for use in an antenna with electronic scanning, appeared at the end of 1954, and publications on the antenna itself - in 1956-1957.

The problem of developing an antenna with electronic scanning is composed of two components:

• 1) the choice of the number of emitters and configurations of their placement;
• 2) Development of phase studies, control of the phase of an electromagnetic wave in emitters.

antenna layout developed in 1954-1955 and tested in June 1955. The antenna was a lattice of four dielectric emitters, ultrahigh-frequency (microwave) wave to which is supplied through phase beams, which are segments of rectangular waveguides, partially filled with ferrite. Ferrite liners are in an alternating field of electromagnets. The outer magnetic field changes the magnetic permeability of ferrite. The change in the magnetic permeability of the medium in which the wave is propagated, changes the phase velocity velocity, as a result, the required phase shift occurs.

How is an antenna with electronic scanning Antennas should be distinguished with

• one-dimensional
• two-dimensional scanning

or, in other words, antennas with a beam movement in one plane and antennas with a beam movement in two planes. Antennas with one-dimensional scanning are needed when working with objects lying in the same plane. An example is an antenna of a radar, providing motion control in the waters of the seaport, where all objects with which the connection is established or followed by observation is located on the water surface. It is different when providing communication with the artificial satellite of the Earth or when moving the movement in the Bolshoi Airport area. In these cases, directions to objects with which the connection is established or followed by observation, can be under different angles both in horizontal and in the vertical plane, therefore the beam of the antenna should move in two planes.

With one-dimensional scanning. The antenna is a ruler of emitters, which in the figure schematically represented as a cross-emitter. Antenna entry is represented by one waveguide or coaxial cable, which is connected to the receiver, transmitter or other radio engineering system. Between the antenna entrance and emitters there is a power divider, and a phase displayer is turned on in the power circuit of each emitter. Phasemators are controlled from a single control device (computer) and form the required phase distribution on emitters. The flat phase front, located at an angle of QK relative to the plane of the emitter location. It is obvious that the main beam of the antenna is formed along the normal with respect to the phase front of the wave, given by the emitters, and, thus, the main beam of the antenna is deflected from the axis of the antenna symmetry also to the angle QK. Recall that from the laws of diffraction of electromagnetic waves it follows that the width of the beam of the antenna is determined by the ratio of the wavelength of the emitted electromagnetic oscillations to the size of the antenna: where DQ is the width of the beam, L is the wavelength, L is the size of the antenna. A sufficiently well-directed antenna must have a beam width of about one angular degree: DQ \u003d 1. Let DQK \u003d 90, then N \u003d 90, that is, the design of the emitter line is quite complicated. Consider an antenna in the form of a lattice of emitters providing electronic beam scanning in two planes. The grille consists of a system of parallel lines of emitters located in the same plane. The number of emitters in the composition of one line is called the number of emitters in the horizontal plane of the NG, and the number of lines is the number of emitters in the vertical plane N. Thus, the total number of emitters in the grille under consideration

Phase shifting devices As shown above, in the power champ chain of each headlight emitter must be a device that provides the required phase shift, a phase displayer. Phase papers for headlamps can be divided into two large groups:

• 1) analog phasemators, a phase shift in which is a continuous function of control exposure (voltage or current);
• 2) Digital (discrete) phasemators, a phase shift in which is given by binary code:

The basis of the analog phaseraders is the material, magnetic or dielectric permeability of which changes under an external influence. This material can serve as a ferrite, which was briefly mentioned above, or a ferroelectric, the dielectric permeability of which depends on the electric field strength. The discreteness of the phase is well fits into the structure of the command control computer, although it generates some errors in the task of the beam coordinates of the antenna, and also leads to a minor Increase the level of lateral petals of the antenna pattern. However, with a large number of headlamp elements, the error arising in this way are averaged and overlook the level that can be neglected.

Phased antenna grille (Headlights)

phased grid, antenna grinning with controlled phases or phase differences (phase shifts) of waves emitted (or accepted) by its elements (emitters). Phase control (phasing) allows: to form (with very diverse arrangements of emitters) the necessary diagram of the radiation (DN) of the headlights (for example, the sharply directed day - beam); Change the direction of the beam of the stationary headlights and so on. Implement the rapid, in some cases, almost rayless, scanning - ray swing (see, for example, scanning radar); To control at certain limits of the form form - change the width of the beam, the intensity (levels) of the side petals, etc. (For this, in the headlights sometimes they are also controlled by the amplitudes of the waves of individual emitters). These and some other feathery properties, as well as the ability to apply modern automation and computer to headlights, led their prospects and widespread use in radio communication (see radio communication), radar (see radar), radio navigation (see Radio navigation), radio astronomy (cm . Radio astronomy), etc. Headlights containing a large number of controlled elements (sometimes 10 4 or more) are part of various terrestrial (stationary and movable), ship, aviation and space radio devices. Intensive developments are underway in the direction of the further development of the theory and techniques of headlights and the expansion of their application.

Headlight structure. Forms, sizes and designs of modern headlamps are very diverse; Their diversity is defined both by the type of emitters used and the nature of their location ( fig. one ). The headlamp scanning sector is determined by the bottom of its emitters. In the headlights with a quick wide-angle swing of the beam are commonly used low-controlled emitters: symmetrical and asymmetrical vibrator , Often with one or more reflectors (for example, in the form of a common mirror for all headlights); Open ends of radio wave , Slotal, horn, spiral, dielectric rod, logooriodic and other antennas. Sometimes large headlights are made up of separate small headlights (modules); The bottom of the latter is oriented towards the main beam of all headlights. In some cases, for example, when a slow rejection of the beam is permissible, the radiators are used as emitters (for example, T. N. Four-member mirrors); In such headlights, the deviation of the beam on a large angle is performed by turning all the antennas and phasing the waves emitted by them; The phasing of these antennas also makes it possible to carry out the ray ray ray ray.

Depending on the required form of the day and the required spatial scanning sector, various mutual positions of the elements are used: along the line (direct or arc); On the surface (for example, flat - in t. n. flat headlights; cylindrical; spherical) or in a given volume (volumelighting). Sometimes the form of the radiating surface of the headlight - opening (see radiation and reception of radio waves) , Determined by the configuration of the object on which headlights is installed (for example, the form of the USS). Headlights with a form of a disclosure similar to the form of the object are sometimes called conformal. Flat headlights are widespread; In them, the beam can scan from the direction of normal to the opening (as in the simphase antenna (see the syphase antenna)) to direction along the opening (as in the antenna running wave (see the antenna traveling wave)). The coefficient of directional action (CBD) of flat headlights when the beam is deviated from the normal to the opening decreases. To ensure wide-angle scanning (in large spatial angles - up to 4 ( erased) Without a noticeable decrease in the CBD, headlights are used with non-planning (for example, spherical) open or a system of flat headlights oriented in various directions. Scanning in these systems is carried out by excitation of respectively oriented emitters and their phasing.

Phase shifts control. According to a method for changing phase shifts, there is a headlights with electromechanical scanning, carried out, for example, by changing the geometric shape of an exciting radio film ( fig. 2. , but); Frequency scanning based on the use of the dependence of phase shifts from the frequency, for example, due to the feeder length, between the adjacent emitters ( fig. 2, b) or dispersion (see dispersion) waves in the radio wave screw; with electrical scanning implemented using phas shifting circuits (see phasos-shifting chain) or phase beams (see phasemator) , controlled by electrical signals ( fig. 2. , c) with smooth (continuous) or stepped (discrete) change in phase shifts.

The greatest possibilities have headlights with electric scanning. They provide the creation of various phase shifts throughout the disclosure and a significant rate of changes in these shifts at relatively small power losses. Ferrite and semiconductor phases (with speed speed are widely used in modern headlights. mKSEK and power losses phased antenna grinning 20%). The operation of phasemators is carried out using a high-speed electronic system, which in the simplest cases manages groups of elements (for example, strings and columns in flat headlights with a rectangular arrangement of emitters), and in the most complex - each phase displayer separately. The rocking of the beam in space can be made both by a predetermined law and the program produced during the work of the entire radio device, which includes headlights.

Features of building headlights. Excitation of headlight emitters ( fig. 3. ) It is produced either using feeder lines, or by means of freely propagating waves (in t. n. quasi-optical headlights), feeder excitation paths along with phasemators sometimes contain complex electrical devices (T. N. diagrams of the following circuits), ensuring the excitation of all emitters from several inputs That allows you to create in space that the scanning rays (in multipath headlamps) corresponding to these inputs. Quasi-optical headlights are mainly two types: passing (lenzovy), in which phaserators and major emitters are excited (with the help of auxiliary emitters) by waves propagating from the total irradiatory, and the reflective - the main and auxiliary emitters are combined, and reflectors are installed on the phasemators outputs. Multipath quasi-optical headlights contain several irradiants, each of which corresponds to their ray in space. Sometimes focusing devices (mirrors, lenses) are used in the formation of DN. The headlights discussed above are sometimes called passive.

The greatest capabilities of the characteristics are the active headlights, in which the transmitter (sometimes and amplitude) transmitter or receiver (sometimes and amplitude) is connected to each emitter or module. fig. four ). The phase control in active headlights can be carried out in the intermediate frequency paths or in the excitation chains of coherent transmitters, receiving heterodynes, etc. Thus, in active headlights, the phase students can operate in wavebands other than the frequency range of antenna; Losses in phasemators in some cases do not directly affect the level of the main signal. Transmitting active headlamps make it possible to accumulate in the capacity of coherent electromagnetic waves generated by separate transmitters. In the receiving active headlights, the joint processing of signals accepted by individual elements allows to obtain more complete information about radiation sources.

As a result of the direct interaction of emitters among themselves, headlight characteristics (coordination of emitters with exciting feeders, knd, etc.) when swinging the beam change. To combat the harmful consequences of the mutual influence of emitters in the headlights sometimes use special methods of compensation of mutual relations between the elements.

Perspectives for headlights. The most important areas of further development of the theory of headlamps include: 1) wide introduction of headlights with large numbers of elements, the development of elements of new types, in particular for active headlights; 2) Development of methods for building headlights with large sizes of discontinuities, including non-equity headlamps with strong-directional antennas located within the whole hemisphere of the Earth (Global Radiothers) , 3) further development of methods and technical means of weakening the harmful effects of mutual communication between elements of headlights; 4) the development of the theory of synthesis and methods of machine design of headlights; 5) Development of the theory and introduction into the practice of new methods of processing information adopted by elements of headlights and the use of this information to manage

Headlights, in particular for the automatic phasing of the elements (self-name) and changes in the form of the day, for example, lowering the level of lateral petals in directions to interference sources (adaptive headlights); 6) Development of methods for managing independent movement of individual rays in multipath headlights.

LIT: Venndic O. G., antennas with non-mechanical movement of the beam, M., 1965; Scanning antenna SCM systems, per. from English, vol. 1-3, M., 1966-71.

M. B. Zakson.

Fig. 1. Structural schemes of some phased antenna arrays (headlights) - linear equidistant with symmetric vibrators and a common mirror (A); linear non -iquidistant with full-powered mirror parabolic antennas (b); flat with rectangular arrangement of horn emitters (B); flat with hexagonal arrangement of dielectric rod emitters (g); conformal with slit emitters (D); spherical with spiral emitters (E); systems of flat phased antenna arrays (g); In - vibrators; F - excitation lines (feeders); S - conductive mirror (reflector); A - mirror antennas; R - Hyphores; BP - exciting radio waves; E - metal screen; Shlitsa emitters; K - conic headlights; C - cylindrical headlights; C - spiral emitters; SE - spherical screen; P - flat phased antenna lattices (dots indicated emitters); L 0 - distance between B; L 1, L 2, L 3 - distances between A.

Fig. 2. Examples of phased antenna grids with electromechanical (A), frequency (b) and electric (B) scanning: sh, - slit emitters; B is a rectangular exciting waveguide; H is a longitudinal plate (knife) with a controlled depth of immersion into the waveguide (serves to change the phase wave velocity in the waveguide); D - throttle grooves; R - Hyphores; Sv - spiral waveguide; Yes - dielectric rod antennas; F - ferrite stem of the phase inspector; Explosives - exciting waveguides; O is the control winding of the phase master; W is a dielectric washer.

Fig. 3. Typical schemes of excitation of phased antenna grids (headlights) with sequential excitation (a), parallel excitation (b), multipath headlights (B), quasi-optical headlights - passing (g) and reflective (D) types: B is an exciting feeder; And - emitters; Mon - absorbing load; L - directional diagram (beam); B 1 - B 4 headlights; DS is a diagram-forming scheme; OI - the main emitters; W - auxiliary emitters; C - combined emitters; O - irradiator; From - reflector; φ is a phase show; The dotted line shows an electromagnetic wave with a flat phase front, radiated headlights, a barcode - with a spherical phase front emitted by the energone.

Fig. 4. Structural diagrams of some active phased antenna decters - transmitting (A), admitting with phasing in the chains of heterodyne (b) and a receiving with phasing in intermediate frequency paths (B): and - emitter; Mind - power amplifier; In - causative agent; C - mixer; G - heterodyne; UPUs - an intermediate frequency amplifier; Su - a summing device; φ is a phasemator.

Great Soviet Encyclopedia. - M.: Soviet Encyclopedia. 1969-1978 .

• - Fazuotoji Gardelinė Antena Statusas T Sritis Radiolektronika Atitikmenys: ANGL. Phased Antenna Array Vok. Phasierte AntennenanordNung, F Rus. Phased antenna lattice, F PRANC. Réseau d ANTENNES PHASÉES, M ... Radiolektronikos Terminų žodynas.

- (phased grid), antenna grid with controlled phases or phase differences (phase shifts) of waves emitted (or accepted) items. Fazing allows, for example, to form the necessary orientation diagram, to manage it ... ... Natural science. encyclopedic Dictionary

- (phased grid), antenna grid with controlled phases or phase differences (phase shifts) of waves emitted (or accepted) items. Fazing allows, for example, to form the necessary orientation diagram, to manage it ... ... encyclopedic Dictionary

phased antenna grille Encyclopedia "Aviation"

phased antenna grille - (headlights), a phased grid, a directional antenna with controlled phases or phase differences (phase shifts) of waves emitted (or accepted) by its elements (emitters). Phase control (phasing) allows you to form the necessary ... ... Encyclopedia "Aviation"

- (AFAR) Variety of phasing antenna lattice (headlights). RLS H050 with AFAR for Pak Fa Presented by NIIP on Max 2009 ... Wikipedia

This term has other values, see the grid. Antenna lattice (AR) A complex directional antenna, consisting of a set of individual inaccessible antennas (emitting elements) located in space in a special way. ... ... Wikipedia

Huge ground headlights of a missile attack warning system on Alaska, USA system of armament management of a modern fighter phased antenna lattice in a wave theory group of antenna emitters, in which relative ... ... Wikipedia

Dedicated to the antennas. Continuing the topic, I want to tell the Haboboboff on the principles of operation of phased antenna arrays (headlights). Headlights found wide use in radar complexes, missile defense, cosmic communication; Application in civilian objects (commercial) is difficult to make the complexity of manufacture and high cost. Perhaps someone will be interested in topics and will come up with an effective use of headlights for commercial use.

What is it?

The headlights are a group of emitters (phaserators, FV), in which the relative phases of signals change comprehensively according to a certain law so that the effective radiation of the headlights is enhanced in the desired direction and is suppressed in all others. The headlights are a matrix, where the element of the matrix is \u200b\u200bFV, \u200b\u200bbut other configurations may have other configurations in space. Figure 1 shows the RLS sector review "Ginger", is part of the Z300V anti-aircraft missile complex. You can see the headlights and irradiating shoes.

Picture 1.

How does phasing occur?

There is a simple formula from the courses of physics: V \u003d C / SQRT (MU * EPS). In this formula V, the phase velocity of the electromagnetic wave, with C - the speed of light in vacuum, Mu is magnetic permeability, EPS is a dielectric constant. From this formula, it can be seen that the phase speed depends on the MJ and Epsilon, and changing these values \u200b\u200bwe can enter the delay of the EM wave through the FV. Therefore, FV is ferrite (we can change their magnetic permeability) and ferroelectric (we can change their dielectric permeability). Power supply to phasemators is carried out by air path (as in Fig. 1) or by means of waveguides (for example, in small-sized anti-aircraft missile systems, Fig. 2).

Figure 2. SPK "TOR".

Headlight diagram in fig. 4: The antenna is a ruler of the emitters, between the power separator and the emitters are included. Ferrite FV is an analog frying of a cylindrical shape, which is wound up management windings. Changing the current in the control windings (defined by the PV control unit) changes magnetic permeability and, accordingly, the phase velocity of the EM wave in the FV. Thus, consistently changing the control signal in the windings The process of forming a wave front may be represented as shown in Figure 3, 4 (one-dimensional case). You can draw an analogy with pebbles that we throw in the water. Another analogy of the work of the headlights can serve as a lens. Figure 5 shows the change in the wave front shape using the lens.

Figure 3. Formation of the wave front.

Figure 4. Headlight diagram.

Figure 5.

Figure 6. Typical radiation chart.

Electrical scanning provides the creation of a variety of phase shifts throughout the disclosure and a significant rate of change of these shifts at relatively small power losses. The operation of phasemators is carried out using a high-speed electronic system, which in the simplest cases manages groups of elements (for example, strings and columns in flat headlights with a rectangular arrangement of emitters), and in the most complex - each phase displayer separately. The rocking of the beam in space can be made both by a predetermined law and the program produced during the work of the entire radio device, which includes headlights.

Pictures to the article can be found in the indicated literature, except for Figure 3. For more detailed familiarization with headlights and control, I can recommend the book Samoilenko and Shishov, "Management of phased antenna lattices".

Literature:

1. O. G. Venndik, "Phased antenna lattice - the eyes of the radio engineering system", 1997

Comparison with passive grid

In a conventional passive lattice, one transmitter with a power of several kilowatt feeds several hundred elements, each of which radiates only dozens of watts of power. The modern microwave transistor amplifier may, however, also produce dozens of watts, and in a radar with an active phased lattice of several hundred modules, each power in dozens of watts, create a generally powerful main ray ray of radar into several kilowatts.

While the result is identical, active lattices are much more reliable, since the refusal of one receiving-transmitting element of the grid distorts the antenna pattern of the antenna, which degrades the characteristics of the locator, but in general it remains operational. The catastrophic failure of the transmitter lamp, which is the problem of ordinary radars, simply cannot happen. Additional benefits - weight savings without a large high-power lamp associated with it with a cooling system and a large high voltage power supply.

Another feature that can only be used in active lattices is the ability to control the enhancement of individual reception-transmitting modules. If this can be done, the range of angles, through which the beam can be rejected, increases significantly, and thus many of the lattice geometry restrictions that have conventional phased grids can be carried away. Such lattices are called lattices of suproles. From the published literature it is unclear whether any existing or projected antenna lattice uses this technique.

disadvantages

Afar technology has two key problems:

Dispersion of power

The first problem is the power dissipation. Due to the shortcomings of microwave transistor amplifiers (MMIC), the efficiency of the module transmitter is typically less than 45%. As a result, the AFAR highlights a large amount of heat that must be scattered to protect the transmitter chips from melting and converting a gallium arsenide - the reliability of GaAs MMIC chips is improved at a low operating temperature. The traditional cooling of air used in conventional computer and avionics is poorly suitable at a high density of packing elements of AFAR, resulting in modern AFARs are cooled with liquid (US projects use Polyalphaolefin (PAO) refrigerant, similar to synthetic hydraulic fluid). A typical liquid cooling system uses pumps that introduce the refrigerant through the channels in the antenna, and then displaced it to the heat exchanger - they can be like an air cooler (radiator) and the heat exchanger in the fuel tank - with the second liquid, the cooling loop of the heat transfer to lead the heat from Fuel tank.

Compared with the usual radar of air-cooled fighter, AFAR is more reliable, but it will consume a large amount of electricity and require more intensive cooling. But AFAR can provide much greater transmitting power, which is necessary for a larger target detection range (an increase in the transmission power, however, has a disadvantage - increasing the trace, through which the enemy radio receiver or RWR can detect radar).

Cost

Another problem is the cost of mass production of modules. For a fighter radar that requires typically from 1000 to 1800 modules, the cost of AFAR becomes unacceptable if the modules cost more than one hundred dollars each. Early modules cost approximately $ 2,000, which did not allow the mass use of AFAR. However, the cost of such modules and MMIC chips is constantly decreasing, since the cost of their development and production is constantly decreasing.

Despite the disadvantages, active phased lattices exceed the usual radar antennas in almost all respects, providing a higher tracking ability and reliability, even with some increase in difficulty and, possibly cost.

The grill is an antenna grid in which controlled phases or phase shifts are present. Phases take waves with elements of the lattice, or emit them with their emitters. With a good controllability of the phases, a proper pattern of the radiation of the phased antenna grid is formed, and the direction of the beam of the stationary lattice changes and the ray swing is performed. In addition, due to the controllability of the phases, the intensity of lateral petals changes, the width of the beam and other forms of the radiation chart. Thanks to similar properties, combined with modern automation tools, phased antenna arrays are quite promising, they are widely used in radio navigation, radio communications, radio astronomy and radar. Antenna lattices with a large number of controlled elements are stationary and movable, terrestrial and air, ship, cosmic and aviation radio devices. The theory and technique of phased antenna arrays to this day is an interesting research, which did not lose their relevance.

The phasned antenna grille is the radiating elements located at the same distance from each other in the same plane. The elements are connected to the microwave band signals, which coincide in their phase and have equal amplitudes. A microwave signal is generated by a master generator, the lamps of the running wave and transistors are enhanced.
The shapes and dimensions of the antenna arrays depend on the type of emitters used and their location. The swing sector of the lattice ray, i.e. scanning, defines the radiation pattern diagram. In those antenna lattices, where wide-angle scanning occurs, symmetric, asymmetrical vibrators with several reflectors, horn, logooriodic, slotted, spiral antennas and other low-controlled emitters are used. Fasted lattices of large dimensions are usually somewhat small lattices. Module orientation diagram, i.e. small phased gratings, corresponds to the direction of the beam of the entire large phased antenna array. Ostrogenated mechanical rotation antennas perform the functions of emitters if a slow radiation deviation is permissible. If it is necessary to deviate the entire phased lattice to a large angle, then all the antennas are rotated.

In the 1960-1970s. The first radar stations used to use phased antenna arrays. Original lattices were used for military purposes.

Phased antenna arrays are an advanced model of flat lattices. In such lattices, due to the constancy of the phases of microwaves, the beam is constant both in shape and direction. When the phases change, the form with the direction of the beam is changed. If the phases are changed by electronics, the change occurs in seconds. It is mainly under the control of the encipheter, the device changing the microwave phases. The computer controls microwaves that pass through the enciffer. By applying the computer, the entire flat grid becomes an antenna, in which the shape of the beam and its direction is programmable.

Electronics-controlled phased lattices were used in large stationary radar and small radars of anti-air defense.

The widespread use of phased antenna arrays in military, industrial and other areas is explained by the fact that phased antennas performed several antennas at once. The narrow rays of the phased lattice were used to escort, wide when searching, flat fan-shaped heights were determined, narrow directional rays were used for flights along the landscape. Other positive characteristics of the phased lattice were the allowance of zero placement, i.e., permission to block the wave of stuff from entering the radio, as well as the automatic direction of antenna in the target direction.

The cost of the phased antenna lattice depends on the amount of radiating elements than them less, the sooner the cost decreases. In radar techniques, as a rule, antenna arrays with a large number of radiating elements are used. A small grill has a wide, little focused beam. The small area of \u200b\u200bsuch a phased lattice reduces the sensitivity to reflected signals, a wide beam contributes to a decrease in the resolution but corner coordinates. If you do not need to observe a large airspace, the shortcomings of a small phased lattice are compensated by attaching it to a large reflector.
The phased antenna lattices have limitations. The range of angles of the beam deviation is limited, the limit is considered to be 45-60 ° from the vertical antenna plane. If the beam deflects to smaller corners, the lattice work is significantly worse.

An important areas of development of phased antenna arrays are considered to be the active implementation of phased lattices with a large number of elements in radio engineering devices, the development of new models of elements, especially for active phased lattices. Active lattices are divided into transmitting, receiving with phasing in heterodyne circuits and a receiving with a phasing in paths with an intermediate frequency. The structural system of such a lattice is a system that consists of a power amplifier, emitter, pathogen, a heterodyne, a phasemator, a summing device, a mixer and an intermediate frequency amplifier.

Another important direction of the development of phased lattices is the development of methods for constructing phased antenna arrays with large raesers, equidistant and non-equidistant with antennas, which are located within the Earth Hemisphere, as well as a further study of methods and technical means that weaken the harmful effects of the relationship between the elements of the phased antenna arrass .

Phased antenna arrays have recently spread widely in many countries of the world. Antenna lattice equipped radar stations in Sweden, Italy, Israel, Great Britain and other countries.

• Following: Phase diagram

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