RU2310257C1 - Waveguide distribution system - Google Patents

Abstract

FIELD: radio communication facilities; waveguide microwave measurement technology and antenna engineering; stand-alone antennas and antenna arrays.

SUBSTANCE: proposed waveguide distribution system designed for operation within wide frequency band (>5 - 7% of f₀) has four line-column dividers each incorporating one distribution column and n lines of multiple-slit directional couplers sequentially integrated by common main-line waveguide and microwave adders. Width of directional-coupler waveguide channels a = (0.7 ± 0.1)λ, where λ is free-space wavelength; its height b ≤ 0.2λ, slit length being not over ≤ 0.2λ. Microwave adder is assembled of four twin T-joints with waveguide channel height not over b ≤ 0.2λ.

EFFECT: enlarged functional capabilities.

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Description

The proposed technical solution relates to the radio engineering industry of communications and can be used in waveguide microwave measuring and antenna technology both independently and as part of antenna arrays.

The small-sized multi-arm waveguide power divider is known [see US patent No. 5196812, NKI 33/113, 1994], consisting of waveguide sections connected to each other along a common wide wall through two elongated holes. The input section branches the microwave energy into several parallel waveguide sections of a similar design.

где λ_в - длина волны в волноводе, а ответвленные каналы ориентированы под углом 90° к оси магистрального волновода.A multi-channel divider is known that uses directional couplers on crossed waveguides in its composition [see US patent No. 3518576, NKI 333-10, 1970], consisting of N directional couplers connected by a rectangular main waveguide, and having N branched square channels located on the side of one of the wide walls of the main waveguide. Two narrow slots located at a distance are used as communication elements in each coupler.

where λ _in is the wavelength in the waveguide, and the branch channels are oriented at an angle of 90 ° to the axis of the main waveguide.

Known multi-channel waveguide divider, consisting of N multi-slit directional couplers, united by a single main waveguide, and having N branched channels oriented at an angle β to the axis of the main waveguide and located on both of its wide walls. Slots are cut in a common wide wall of the branch and trunk channels [see Patent No. 2158049 of the Russian Federation, Н01Р 5/18, H01Q 13/26, 03.1999].

The closest in its technical essence and design to the proposed technical solution is the distribution system [Waveguide distribution system of an onboard antenna with electronic beam control, ed. A.I.Sinani, R.D. Pozdnyakova, Mitin V.A., Sat. "Antennas", issue 6 (61) 2002], consisting of four row-column dividers powered by a microwave adder, each of which includes one column distributor and n line rulers.

Both column distributors and row rulers consist of multi-gap directional couplers (BUTs) connected in series in each distributor by a common trunk waveguide.

The main disadvantages of the known technical solutions are:

- limited width of the working frequency range (Δf ~ 5-7% f ₀ ), where f ₀ is the design frequency;

и связанное с этим нарушение амплитудного распределения в апертуре фазированной антенной решетки (ФАР) в диапазоне более 5-7% f₀, где P_i - мощность на выходе i канала линеек, Р_вх - мощность на входе линейки;- a strong change in the amplitude distribution of the rulers

and the associated violation of the amplitude distribution in the aperture of the phased array antenna (PAR) in the range of more than 5-7% f ₀ , where P _i is the power at the output of the i channel of the rulers, P _in is the power at the input of the ruler;

- violation of the functions of the microwave adder and, as a consequence, the destruction of the total-differential characteristics of the waveguide distribution system (HRS) and their corresponding radiation patterns (DN) (for the total channel - Σ, for the difference channels - Δ _АЗ and Δ _УМ , according to the difference - differential channel - ΔΔ) in the PAR in the range of more than 5-7% f ₀ .

The technical result of the proposed solution is to expand the operating frequency range while simultaneously stabilizing in this range the amplitude-phase distribution in the headlight opening.

The essence of the invention consists in improving the functionality of HRV when operating in a wide frequency range (> 5-7% f ₀ ), which is ensured by the fact that in a waveguide distribution system consisting of four horizontal column dividers, each of which includes multi-slot directional couplers connected in series by a common trunk waveguide, one column distributor and n line rulers, and a microwave adder, the waveguide channels of directional couplers are made of width a = (0.7 ± 0.1) λ, where λ is the wavelength in free space and height b≤0.2λ, in multi-slot directional couplers, the length of slots 1 does not exceed ≤0.3λ, and the microwave adder is made of four double tees with waveguide channels with a height of no more than b≤ 0.2λ [see "Reference to the elements of electronic devices", ed. Doctor of Technical Sciences A.A. Kulikovsky, Ph.D. V.I. Dulina, M.S. Zhuk, Moscow, "Energy", 1977, p. 455, 555-556].

The feasibility of the proposed technical solution is determined by the fact that

, а другой - к а=λ и исключить синфазное сложение отраженных от НО сигналов;1) the indicated limits of the width of the waveguide channels of the HRV: a = (0.7 ± 0.1) λ - allow us to ensure the transmission band of the H ₁₀ wave through the HRV up to 40% f ₀ and remove the fundamental limitation of the working frequency range that occurs every time in microwave devices, when it uses waveguide channels with very different dimensions "a", one of which is close to

and the other to a = λ and exclude in-phase addition of signals reflected from the BUT;

2) reducing the height of all waveguides of row-column dividers to size b≤0.2λ also allows you to expand the working range of the HRV and stabilize the amplitude distribution in this range, providing efficiency ≥0.5-0.6;

3) the restriction imposed on the dimensions of the slit: 1≤0.3λ - allows you to stabilize the transient attenuation of BUT distributors-columns and rulers-rows in a wide frequency range and thereby provide stabilization of the amplitude distribution and efficiency of the HRV in this frequency band compared to the prototype;

4) the use of double tees with a channel height b≤0.2λ as part of the microwave adder allows expanding the working frequency band of the microwave adder to 35–40% f ₀ , in which its ability to form an amplitude-phase distribution corresponding to Σ-Δ radiation patterns HEADLIGHT.

As a result of the proposed technical solution, stable amplitude-phase characteristics of the HRV are ensured in the range of at least (35-40%) f ₀ .

The essence of the proposed technical solution is illustrated by the following description and the attached drawings:

Figure 1 shows a diagram of a waveguide distribution system.

Figure 2 shows the amplitude distribution of the prototype (for the vertical plane) in the frequency range 40% f ₀ .

Figure 3 shows the amplitude distribution (AR) (for the vertical plane) of a particular implementation of the proposed technical solution in the range up to 40% f ₀ .

The waveguide distribution system contains

- four row-column dividers (1, 2, 3, 4), each of which includes one column distributor (5 _1-4 ) and n-line rows (6 _1-n );

- each of the four column distributors and row rulers is made of multi-slot directional couplers (7), connected in series in each column distributor and in each row ruler with a single main waveguide (8), and

- A microwave adder (9), consisting of four double tees (10), having four inputs: total (Σ), difference Δ _АЗ , Δ _УМ and difference-difference (ΔΔ).

An example of a specific implementation of the proposed technical solution:

- HRV includes four row-column dividers, each of which contains a column distributor and fourteen line rulers, consisting of NO, combined in each distributor-column and ruler-row with its main waveguide, and forming the corresponding branch channels to the number of NO. The number of BUTs in the column distributor (for example, j = 14), in the line rulers (for example, I = 14-44).

- Row-column dividers have the following sections of the waveguide channels:

1) trunk and branch waveguides of the distributor-column: a = 0.7λ, b = 0.15λ;

2) the main waveguides of line rulers: a = 0.7λ, b = 0.2λ;

3) branch channels of line rulers: a = 0.65λ, b = 0.12λ;

- the size of the slots in the field of communication BUT:

- the length of the slits l = (0.3-0.24) λ;

- The microwave adder is made of four double tees with a waveguide channel height of 0.15λ.

Implemented electrical characteristics of the proposed distribution system:

- the operating frequency range up to 40% f ₀ , which ensures the efficiency of the HRV;

- the maximum change in efficiency and amplitude distribution on the example of the distributor-column in the frequency range up to 40% f _{0 is} shown in figure 3.

The principle of operation of the proposed device (analysis is carried out for the operating mode of the HRV for transmission) is as follows:

Microwave energy from any of the inputs of the HRV (total Σ, differential Δ _UM and Δ _AZ or difference-difference ΔΔ) is divided into four equal parts in the microwave adder (uneven distribution of power and efficiency are the main characteristics of the adder) and enters the main channels (8) column distributors (5), respectively. The phases of the signals in the channels (8) are determined by the fact that the side of which inputs are fed by the HRV, as a result of which four row-column dividers (1-4) form the same amplitude distributions with the following mutual phases:

- on the total (Σ) channel - all dividers are in-phase;

- on the difference channels (Δ _AZ and Δ _UM ) - pairwise antiphase in the azimuthal and elevation planes, respectively, and

- on the difference-difference channel (ΔΔ) - all adjacent dividers are mutually antiphase.

The stability of the main amplitude characteristics of the microwave adder in the frequency range and the preservation of phase relations between the dividers (1-4) provide the formation of the total-difference characteristics of the HRV and, accordingly, the total-difference MDs in the headlamp during frequency tuning in a wide frequency band. This problem is solved by using double tees made of waveguides with a height b <0.2λ.

The shape of the amplitude distribution and the efficiency of the HRV is determined by the choice of the length of the communication slots 1 and the sections of the waveguide channels (a, b) in the distributors-columns and rulers-rows. A change in the shape of the AR in the frequency range is due to a change in the transition attenuation (Ln) of the BUT. In a wide frequency band (> 20% f ₀ ), the transient attenuation of the directional couplers in the general case varies greatly when the operating frequency is tuned, which leads to a strong distortion of the shape of the amplitude distribution (Fig. 2). The change in AR with a change in frequency in the proposed technical solution is minimized by limiting the size of the communication slots of the directional couplers (1≤0.3λ) and waveguide channels (a = (0.7 ± 0.1) λ; b≤0.2λ), which allows you to realize an additional positive effect - to improve both the layout and the weight characteristics of the HRV, to ensure the reduction of the steps of the radiating elements in the aperture of the antenna array, important for wide-angle scanning.

Thus, the technical and economic advantages of the proposed technical solution compared to the prototype are to increase the working range of the HRV frequencies up to 35-40% f ₀ while stabilizing the amplitude-phase distribution in this range and in addition to this weight reduction, improving the compactness of the structure, and when used as part of a phased array in expanding its scanning sector by reducing the waveguide channels of the HRV and correspondingly reducing the steps of the emitters in the aperture of the lattice.

Claims (1)

A waveguide distribution system (HRV), consisting of four row-column dividers, each of which consists of multi-slot directional couplers, sequentially combined by a common main waveguide, one column distributor and n line rulers, and a microwave adder the fact that the channels of the directional couplers are made of a width a = (0.7 ± 0.1) λ, and a height b≤0,2λ, where λ is the wavelength in free space, and the length of the slots in the multi-slot directional couplers does not exceed 1≤0 , 3λ, moreover, microwave mmator constructed of four double tees with a height of not more waveguide channels b≤0,2λ.

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