RU168153U1 - CONTROLLABLE COMMUNICATED PHASE ANTENNA ARRAY - Google Patents

Abstract

The utility model relates to antenna technology. A phased antenna array with controlled links, comprising N emitters, N amplifiers, a unit for forming controlled links, N controlled phase shifters of the PAR, an adder of PAR, in which the unit for forming controlled links includes N input dividers, a block for generating compensation radiation patterns, N output adders, moreover, the block forming the compensation radiation patterns contains N input controlled phase shifters, an adder, divider, N output controlled phase shifters. Additionally, (K-1) blocks for the formation of controlled relationships are introduced. Moreover, each of the K blocks of the formation of controlled connections contains N input dividers having one input and (M + 1) outputs, N output adders with (M + 1) inputs and one output each, as well as M blocks of the formation of compensation radiation patterns with N inputs and N outputs, with K controlled link forming units connected in series, and N outputs of the last controlled link forming unit connected via N controlled phase shifters of the PAR to the corresponding N inputs of the PAR of the adder. In this case, i.e., the outputs of the N input dividers are connected to the corresponding N inputs of the i-th block of the formation of the compensation radiation patterns, and the N outputs of the i-th block of the formation of the compensation radiation patterns are connected to the corresponding ith inputs of the N output adders, and the outputs (M + 1) N input dividers are connected to the inputs (M + 1) of the corresponding N output adders. The technical result is to reduce the level of interference. 2 ill.

Description

The proposed phased antenna array (PAR) with controlled communications relates to the field of antennas and can be used in radio engineering devices with a phased array operating in difficult interference conditions.

Known PARs with uncontrolled (fixed) connections [1], into the feeder paths of which interelement connections were introduced to reduce the depth of dips in partial radiation patterns of emitters in the PAR. Such connections in the PAR can not be used to suppress interfering signals.

In [2], a headlamp with controlled communications was considered, the use of which allows the suppression of interfering signals from only one source of interference. A disadvantage of the known headlamps with controlled communications is that it does not allow suppressing interfering signals if the number of interference sources is more than one. This headlamp is the closest in technical essence to the proposed headlamp and adopted as a prototype.

A prototype diagram is shown in FIG. 1 and includes N emitters (1), N amplifiers (2), a unit for the formation of controlled links (BFUS) (3), N controlled phase shifters of the PAR (4) and an adder of the PAR (5). Moreover, BFUS (3) contains N input dividers (6), the inputs of which are the corresponding N inputs of the BFUS and have two outputs each; N output adders (7) having two inputs and one output each, which are the corresponding N outputs of the BFUS; one unit for the formation of compensation radiation patterns BFKDN (8), which has N inputs and N outputs. BFKDN consists of N input controlled phase shifters (9), the inputs of which are the corresponding N inputs of BFKDN; N output controlled phase shifters (10), the outputs of which are the corresponding outputs BFKDN; an adder (11) having N inputs and one output, as well as a divider (12) with one input and N outputs.

The disadvantage of the prototype is that with the simultaneous exposure to two or more interfering signals coming from different directions θ, such a headlamp ceases to be anti-interference.

The essence of the proposed PAR is that it additionally includes (K-1) BFUS, a diagram of which is presented in FIG. 2. Thus, the total amount of BFUS (3.1, 3.2, 3.K) in the proposed PAR will be K. The required number of BFUS is the number K depends on the required level of suppression of interfering signals. Each of K BFUS contains N input dividers (6A), which have one input, which is the corresponding input of the BFUS, and (M + 1) outputs; N output adders (7A), each having (M + 1) input and one output, which are the corresponding outputs of the BFUS. In addition, each of K BFUS includes M BFKDN, where M is the maximum specified number of sources of interfering signals. BFUS in the amount of K pieces are connected in series so that the N outputs of each previous BFUS are connected to the corresponding N inputs of the subsequent BFUS.

N outputs of the last Kth BFUS are connected through N controlled phase shifters of the PAR (4) to the corresponding N inputs of the phased array adder (5), the output of which is the output of the PAR with controlled communications. In this case, the i-th outputs of N input dividers (6A) are connected to the corresponding N inputs of the i-th BFKDN (8.i), and the outputs of the i-th BFKDN (8.i) are connected to the corresponding i-inputs of the N output adders (7A) . In this case, the (M + 1) -th outputs of N input dividers (6A) are connected to the corresponding (M + 1) inputs of N output adders (6A).

The proposed headlamp with controlled communications works as follows.

Let in the directions θi, where i varies from 1 to M, there are M sources of interfering signals. At the outputs of the emitters (1), the received amplitudes of each of the M interference signals will be the same, and their phases will have a progressive linear incursion determined by the ratio:

ϕ _{i phases} = (2π nd _x / λ) sinθ _i

The received signals are amplified by amplifiers (2) and fed to the inputs of the BFUS (3.1), namely to the inputs of the dividers (6A), where they are divided into (M + 1) equal parts. From the first outputs of N dividers (6A), the signals are fed to the corresponding inputs of the first BFKDN (8.1), namely, to the inputs of N phase shifters (9.1), in which they acquire a linear phase shift:

ϕ _{1 phases n} = - (2π nd _x / λ) sinθ ₁ ,

where n takes values from 1 to N,

which ensures the in-phase distribution of N signals at the inputs of the adder (11) BFKDN (8.1), received from the first source of interference (located at an angle θ ₁ relative to the normal to the aperture of the PAR). The phase distributions at the outputs of the input phase shifters (9.1) from the remaining (M-1) interference signals will have linear slopes:

ϕ _{i phases n} + ϕ _{1 phases n} = (2π nd _x / λ) sinθ i- (2π nd _x / λ) sinθ ₁

From the i-th outputs of N input dividers (6A) to the BFUS (3.1), the signals are fed to the corresponding inputs of the i-th BFKDN (8.i), namely the inputs of the N input phase shifters (9.i) BFKDN (8i), in which acquire a phase linear incursion:

ϕ _{i phases n} = - (2π nd _x / λ) sinθ _i

which provides an in-phase distribution of N signals at the inputs of the adder (11i) to the BFKDN (8i) received from the ith interference source (which is at an angle θ _i relative to the normal to the PAR aperture). The phase distributions at the outputs of the phase shifters (9i) for the remaining (M-1) interference signals will have linear slopes.

From the outputs of N phase shifters (9.i), the signals are fed to the N inputs of the adders (11.i), at the outputs of which there is a common-mode addition of signals received by N emitters from the i-th interference source and non-common phase addition from the remaining (M-1) interference signals . Thus, at the outputs of the adders (11.i), compensation radiation patterns (CDDs) are formed with maxima in the directions to ie sources of interference θ _i . In the dividers (12.i), the signals are divided into N equal parts and passing further through the output phase shifters (10.i) in the BFKDN (8.i) the signals acquire an additional phase:

ϕ _{i phases n} = (2π nd _x / λ) sinθ _i + π,

which leads to antiphase summation of the signals arriving at the ith and at the (M + 1) th inputs of the N adders (7A) from the ith interference source, ensuring their full compensation.

However, at the outputs of adders (7A) in BFUS (3.1), the signals from M interference sources will not be completely suppressed, since the KDN generated at the output of the adder (9.i) with the maximum direction to the i-th interference signal source receives interference signals not only from i -th source of interference, but also from the remaining M-1 sources received by the side lobes of the i-th KDN, from where they come to the outputs of the adders (7A). The resulting amplitude of the signal from the interference source with number i to the outputs of the adders (7A) will be equal to:

A ⁽¹⁾ _i = A _i × (δ ¹ ₁ + δ ¹ ₂ + ... δ ¹ _i-1 ... + .δ ¹ _{i + 1} ++ δ ¹ _M ), where A _i is the complex amplitude of the interfering signal from i- of the source of interference at the outputs of the input dividers (6A), and δ ¹ _i is the level of the corresponding side lobes of complex CDNs formed at the outputs of the adders (11.1), (11.2), ..., (11.i-1), (11.i + 1), ... (11.M). Thus, interference signals from M interference sources at the output of BFUS 3.1 will be suppressed only partially. So, for example, the first interference coming from the direction θ ₁ corresponding to the maximum of the first KDN formed in the BFKDN (8.1) completely compensates at the outputs of the adders (7A) the signals received by the emitters from the first interference source. However, the signals from the remaining (M-1) interference sources acting on the side lobes of the first CDN will be present in the same first KDN, and these interference will remain uncompensated at the outputs of the adders (7A). Therefore, the amplitudes of the interfering signals at the outputs of the BFUS (3.1) are reduced in comparison with the amplitudes at the inputs of the BFUS (3.1) only by an order of magnitude of the average level of the side lobes of the CDF.

Further, from the outputs of the BFUS (3.1), the signals are fed to the inputs of the BFUS (3.2), where, by analogy with the operation of the BFUS (3.1), the amplitudes of the interfering signals at the outputs of the BFUS (3.2) are further reduced by the same value of average level of the side lobes of the CDN. Based on a given level of suppression of interfering signals, it is possible to determine the required number K of cascades of BFUS (3.K). The above conclusions are confirmed both analytically and by computer modeling in the MatLAB system. So, if the level of the side lobes of the KDN will be minus 25 dB, then the interference signals at the outputs of the BFUS (3.1) in comparison with their amplitudes at the inputs will be suppressed by 25 dB, at the outputs of the BFUS (3.2) by 50 dB, and at the outputs of the BFUS (3.3) by 75 dB, which is sufficient, for example, with the existing jamming capacities used against radar stations to suppress their interference signals to the level of the noise of the receiving devices. Thus, in the case of using the proposed headlamp for radar stations, it is sufficient to limit ourselves to three BFUSs included in series.

The application of the proposal allows us to provide the required noise immunity of the PAR in conditions of simultaneous exposure to a given number M of interference sources.

Elements of the proposed PAR (phase shifters, dividers, combiners) can also be implemented in digital form, so the possibility of failure of individual PAR units is eliminated, and the cost and complexity of the design are also reduced. The described principles for the creation of controlled connections obviously apply to flat headlamps, and can also be used for other types of headlamps: cylindrical, spherical, etc., and the use of unequal-amplitude totalizers (for example, with an amplitude distribution falling from center to the edges), will reduce the level of the side lobes KDN and reduce the required number of stages K to obtain the desired level of suppression of interfering signals.

Sources used in filling out the application:

1. N. Amity, V. Galindo. Theory and analysis of phased array antennas. Ed. "Peace". Moscow, 1974 - p. 421-430.

2. Andreev V.F., Voronov R.Kh. The method of formation of dips in partial radiation patterns of emitters of receiving AFAR / in collection. tr 18th International Conference “Digital Signal Processing and its Application” Moscow, DSPA-2016

Claims (1)

A phased antenna array with controlled links, comprising N emitters, N amplifiers, a unit for forming controlled links, N controlled phase shifters of the PAR, an adder of PAR, in which the unit for forming controlled links includes N input dividers, a block for generating compensation radiation patterns, N output adders, moreover, the unit for forming compensation radiation patterns contains N input controlled phase shifters, an adder, a divider, N output controlled phase shifters, characterized in that additionally introduced (K-1) blocks of formation of controlled connections, each of K blocks of formation of controlled connections contains N input dividers having one input and (M + 1) outputs, N output adders with (M + 1) inputs and one output each , as well as M blocks for the formation of compensation radiation patterns with N inputs and N outputs, and K blocks for forming controlled connections are connected in series, and N outputs of the last block for forming controlled connections are connected through N controlled phase shifters of the PAR to existing N inputs of the headlamp adder, i.e., the outputs of the N input dividers are connected to the corresponding N inputs of the i-th block of the formation of compensation radiation patterns, and the N outputs of the i-th block of the formation of the compensation radiation patterns are connected to the corresponding i-inputs of the N output adders, and the outputs (M + 1) of the N input dividers are connected to the inputs (M + 1) of the corresponding N output adders.

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