Universal hole-free MISC array antenna and design method thereof

Abstract

The invention provides a universal hole-free MISC array antenna and a design method thereof. The method comprises the following implementation steps: determining a universal hole-free MISC array design principle; a design example of an enhanced MISC configuration with odd maximum array element spacing is given based on a nonporous MISC array design principle, and the design example comprises the steps of determining the number of array elements, an array element internal spacing distribution set and an array element position distribution set; calculating the continuous degree of freedom of the array configuration; and calculating weighting functions omega (1), omega (2) and omega (3) of the array configuration. The array configuration designed by the invention has a non-porous differential common array, so that the degree of freedom of the array can be effectively improved, and the angle measurement performance is improved from the array design level.

Description

Technical Field

[0001] The invention belongs to the technical field of array antenna design, and in particular relates to a universal hole-free MISC array antenna and a design method thereof. Background Art

[0002] Array design is an important link in the field of array signal processing, and array performance will directly affect algorithm performance. Sparse arrays break through the Nyquist sampling limitation by adopting certain rules for sparse array arrangement, and improve array freedom and effective array aperture. The most typical ones are coprime arrays and their derivative arrays and nested arrays and their derivative arrays. Different from the array configuration design carried out from the perspective of sensor array arrangement, the Maximum Inter-Element Spacing (IES) Constraint (MISC) provides a new perspective for sparse array design, which has the advantages of simple structure and easy capture of array element distribution pattern. However, some existing sparse array designs based on the MISC principle have holes, and a general hole-free MISC array design method needs to be studied. Summary of the invention

[0003] The present invention aims at the deficiencies in the prior art and provides a universal hole-free MISC array antenna and a design method thereof.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] In a first aspect, the present invention provides a universal non-aperture MISC array antenna, wherein in the array element internal spacing distribution set of the MISC array, the maximum array element spacing is M, and the array element internal spacing distribution subsets on both sides are respectively and Among them, M a and Mb represent the array element spacing on both sides, n a and n b Respectively represent the array element spacing M a and M b The number of duplicates, M a +M b =M,|n a -n b |≤1; if M is an even number, M a The value of is M / 2, M / 2-1 or M / 2+1, and the corresponding M b The value of is M / 2, M / 2+1 or M / 2-1; if M is an odd number, M a The value of is (M+1) / 2 or (M-1) / 2, and the corresponding M bThe value of is (M-1) / 2 or (M+1) / 2; the number r of the maximum array element spacing M satisfies NM-1≤r≤NM, and r is a positive integer.

[0006] Optionally, the maximum array element spacing M is an odd number, N represents the number of array elements, N>12, and the internal spacing distribution set of array elements for:

[0007]

[0008] Where M s =(M+1) / 2, M h =(M-5) / 2, r = NM; the array configuration consists of 6 uniform linear arrays ULA, and the array element spacing of each ULA is 1, 3, M respectively s -1, M, M s , 1, superscript M h , 2, r, 3, M h Indicates the number of repeated items corresponding to the array element spacing;

[0009] Array element position distribution set for:

[0010]

[0011] Wherein, ULA1 to ULA6 represent six uniform linear arrays respectively, and IES represents the array element spacing.

[0012] Optionally, the continuous degree of freedom of the array configuration uDOF=-2M 2 +2MN+7M-6.

[0013] Optionally, three weight functions ω(1), ω(2) and ω(3) used to characterize the mutual coupling effect between array elements in the array configuration are respectively:

[0014] ω(1)=M-5;

[0015] ω(2) = M-7;

[0016]

[0017] Wherein, the weight function ω(l) represents the number of sensor pairs corresponding to the common array index, and the above formula shows that in this array configuration, the number of sensor pairs with a common array index of 1 is M-5; the number of sensor pairs with a common array index of 2 is M-7; when the number of array elements is 13≤N≤19, the number of sensor pairs with a common array index of 3 is 1; when the number of array elements is N≥20, the number of sensor pairs with a common array index of 3 is M-8.

[0018] In a second aspect, the present invention provides a general method for designing a hole-free MISC array antenna, comprising the following steps:

[0019] Step 1: Determine the design principle of the hole-free MISC array, specifically: define the maximum array element spacing as M, and the internal spacing distribution subsets of the array elements on both sides are and Among them, M a and M b Respectively represent the array element spacing on both sides, n a and n b Respectively represent the array element spacing M a and M b The number of duplicates, M a +M b =M,|n a -n b |≤1; if M is an even number, M a The value of is M / 2, M / 2-1 or M / 2+1, and the corresponding M b The value of is M / 2, M / 2+1 or M / 2-1; if M is an odd number, M a The value of is (M+1) / 2 or (M-1) / 2, and the corresponding M b The value of is (M-1) / 2 or (M+1) / 2; the number r of the maximum array element spacing M satisfies NM-1≤r≤NM, and r is a positive integer;

[0020] Step 2: Based on the hole-free MISC array design principle, the MISC array configuration is designed, including determining the number of array elements, the array element internal spacing distribution set, and the array element position distribution set.

[0021] Optionally, in step 2, the MISC array configuration is designed as follows:

[0022] For an array configuration with N elements, N>12, define the maximum element spacing And M is an odd number, the internal spacing distribution set of the array element for:

[0023]

[0024] Where M s =(M+1) / 2, M h =(M-5) / 2, r = NM; the array configuration consists of 6 uniform linear arrays ULA, and the array element spacing of each ULA is 1, 3, M respectively. s -1, M, M s , 1, superscript M h , 2, r, 3, M h Indicates the number of repeated items corresponding to the array element spacing;

[0025] Array element position distribution set for:

[0026]

[0027] Wherein, ULA1 to ULA6 represent six uniform linear arrays respectively, and IES represents the array element spacing.

[0028] Optionally, the continuous degree of freedom of the array configuration uDOF=-2M 2 +2MN+7M-6.

[0029] Optionally, three weight functions ω(1), ω(2) and ω(3) used to characterize the mutual coupling effect between array elements in the array configuration are respectively:

[0030] ω(1)=M-5;

[0031] ω(2) = M-7;

[0032]

[0033] Wherein, the weight function ω(l) represents the number of sensor pairs corresponding to the common array index, and the above formula shows that in this array configuration, the number of sensor pairs with a common array index of 1 is M-5; the number of sensor pairs with a common array index of 2 is M-7; when the number of array elements is 13≤N≤19, the number of sensor pairs with a common array index of 3 is 1; when the number of array elements is N≥20, the number of sensor pairs with a common array index of 3 is M-8.

[0034] The beneficial effects of the present invention are as follows: a universal hole-free MISC array antenna and a design method thereof proposed in the present invention provide a universal hole-free MISC array design principle, which effectively improves the array degree of freedom while realizing a "hole-free" differential array, can balance the array degree of freedom and mutual coupling, and improve the angle measurement performance from the array design level. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a flow chart of a general design method for a hole-free MISC array antenna.

[0036] Figure 2 The DOF ratio and the mutual coupling of the design example (GEMISCo) of the enhanced MISC configuration with odd maximum element spacing are compared with the comparison arrays (MISC, EMISC, IMISC, xMISC), where the DOF ratio is defined as γ uDOF =log10((uDOF + -1) / 2N), uDOF + Characterizes the positive portion of the continuous degrees of freedom. DETAILED DESCRIPTION

[0037] The present invention will now be described in further detail with reference to the accompanying drawings.

[0038] In one embodiment, if Figure 1 As shown, the present invention proposes a general method for designing a hole-free MISC array antenna, comprising the following steps:

[0039] Step 1: Derive general hole-free MISC array design principles, including:

[0040] (1) Define the maximum inter-element spacing in the inter-element spacing distribution set (IES) as M, and define the inter-element spacing distribution subsets on both sides as and Then M a +M b =M,|n a -n b |≤1.

[0041] (2) If M is an even number, M a The value of is M / 2, M / 2-1 or M / 2+1, and the corresponding M b The value of is M / 2, M / 2+1 or M / 2-1; if M is an odd number, M a The value of is (M+1) / 2 or (M-1) / 2, and the corresponding M b The value of is (M-1) / 2 or (M+1) / 2.

[0042] (3) In order to increase the array degree of freedom, the number r of the maximum array element spacing M satisfies NM-1≤r≤NM, where r is a positive integer.

[0043] Satisfying principles (1)-(3), as long as the number of "1"s in the internal spacing distribution set of the array elements is large enough, the designed MISC array has a hole-free differential common array.

[0044] Step 2: Based on the strategy in step 1, a design example of an enhanced MISC configuration with an odd maximum element spacing is given, including:

[0045] (1) Design the internal spacing distribution set of array elements: For an array configuration with N array elements (N>12), define the maximum array element spacing as And M is an odd number, M s =(M+1) / 2, M h =(M-5) / 2, r = NM, the inter-element spacing distribution set (Inter-Element Spacing, IES) is expressed as:

[0046]

[0047] In the formula, the array configuration consists of 6 uniform linear arrays ULA, and the array element spacing of each ULA is 1, 3, M respectively. s -1, M, M s , 1, superscript M h , 2, r, 3, M h Indicates the number of repetitions corresponding to the array element spacing.

[0048] (2) Design the corresponding array element position distribution set:

[0049]

[0050] Wherein, ULA1 to ULA6 represent six uniform linear arrays respectively, and IES represents the array element spacing.

[0051] Step 3: Based on the design example of the enhanced MISC configuration given in step 2, calculate the continuous degrees of freedom of the array configuration uDOF = -2M 2 +2MN+7M-6.

[0052] Step 4: Define the weight function ω(l) to represent the number of sensor pairs corresponding to the common array index; according to the array element position distribution given in step 2, calculate the three weight functions ω(1), ω(2) and ω(3) used to characterize the mutual coupling effect between array elements in the array configuration, which are ω(1)=M-5, ω(2)=M-7 and The above results show that in this array configuration, the number of sensor pairs with a common array index of 1 is M-5; the number of sensor pairs with a common array index of 2 is M-7; when the number of array elements is 13≤N≤19, the number of sensor pairs with a common array index of 3 is 1; when the number of array elements is N≥20, the number of sensor pairs with a common array index of 3 is M-8.

[0053] In another embodiment, the present invention proposes a universal non-aperture MISC array antenna, which is obtained by adopting the design method of the above embodiment. In the array element internal spacing distribution set of the MISC array, the maximum array element spacing is M, and the array element internal spacing distribution subsets on both sides are respectively and Among them, M a and M b Respectively represent the array element spacing on both sides, n a and n b Respectively represent the array element spacing M a and M b The number of duplicates, M a +M b =M,|n a -n b |≤1; if M is an even number, M aThe value of is M / 2, M / 2-1 or M / 2+1, and the corresponding M b The value of is M / 2, M / 2+1 or M / 2-1; if M is an odd number, M a The value of is (M+1) / 2 or (M-1) / 2, and the corresponding M b The value of is (M-1) / 2 or (M+1) / 2; the number r of the maximum array element spacing M satisfies NM-1≤r≤NM, and r is a positive integer. The array element internal spacing distribution set, array element position distribution set, continuous degrees of freedom and weight function of the array configuration are the same as those in the previous embodiment, so they will not be repeated here.

[0054] Figure 2 The DOF ratio and mutual coupling of a design example (GEMISCo) of an enhanced MISC configuration with an odd maximum element spacing disclosed in the present invention and a comparison array (MISC, EMISC, IMISC, xMISC) are shown in the two-dimensional plane distribution diagram. The number of elements is set to 20. Figure 2 It can be seen that the joint distribution points of GEMISCo are approximately located on the diagonal of the two-dimensional plane, indicating that the array configuration can effectively balance the array degrees of freedom and mutual coupling.

[0055] In summary, the present invention discloses a universal hole-free MISC array antenna and a design method thereof, and provides a universal hole-free MISC array design principle, which effectively improves the array degree of freedom while realizing a "hole-free" differential array. In addition, it can effectively balance the array degree of freedom and mutual coupling, and improve the angle measurement performance from the array design level.

[0056] The above are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should be regarded as the protection scope of the present invention.

Claims

1. A universal hole-free MISC array antenna, characterized in that: In the array element internal spacing distribution set of the MISC array, the maximum array element spacing is M, and the array element internal spacing distribution subsets on both sides are respectively and Among them, M a and M b Respectively represent the array element spacing on both sides, n a and n b Respectively represent the array element spacing M a and M b The number of duplicates, M a +M b =M,|n a -n b |≤1; if M is an even number, M a The value of is M / 2, M / 2-1 or M / 2+1, and the corresponding M b The value of is M / 2, M / 2+1 or M / 2-1; if M is an odd number, M a The value of is (M+1) / 2 or (M-1) / 2, and the corresponding M b The value of is (M-1) / 2 or (M+1) / 2; the number r of the maximum array element spacing M satisfies NM-1≤r≤NM, and r is a positive integer.

2. A universal non-aperture MISC array antenna as claimed in claim 1, characterized in that: The maximum array element spacing M is an odd number, N represents the number of array elements, N>12, and the internal spacing distribution set of array elements for: Where M s =(M+1) / 2, M h =(M-5) / 2, r = NM; the array configuration consists of 6 uniform linear arrays ULA, and the array element spacing of each ULA is 1, 3, M respectively s -1, M, M s , 1, superscript M h , 2, r, 3, M h Indicates the number of repeated items corresponding to the array element spacing; Array element position distribution set for: Wherein, ULA1 to ULA6 represent six uniform linear arrays respectively, and IES represents the array element spacing.

3. A universal non-aperture MISC array antenna as claimed in claim 2, characterized in that: The continuous degree of freedom of the array configuration uDOF = -2M 2 +2MN+7M-6.

4. A universal non-aperture MISC array antenna as claimed in claim 2, characterized in that: The three weight functions ω(1), ω(2) and ω(3) used to characterize the mutual coupling effect between array elements in the array configuration are: ω(1)=M-5; ω(2) = M-7; Wherein, the weight function ω(l) represents the number of sensor pairs corresponding to the common array index, and the above formula shows that in this array configuration, the number of sensor pairs with a common array index of 1 is M-5; the number of sensor pairs with a common array index of 2 is M-7; when the number of array elements is 13≤N≤19, the number of sensor pairs with a common array index of 3 is 1; when the number of array elements is N≥20, the number of sensor pairs with a common array index of 3 is M-8.

5. A method for designing a universal hole-free MISC array antenna, characterized in that: The steps include: Step 1: Determine the design principle of the hole-free MISC array, specifically: define the maximum array element spacing as M, and the internal spacing distribution subsets of the array elements on both sides are and Among them, M a and M b Respectively represent the array element spacing on both sides, n a and n b Respectively represent the array element spacing M a and M b The number of duplicates, M a +M b =M,|n a -n b |≤1; if M is an even number, M a The value of is M / 2, M / 2-1 or M / 2+1, and the corresponding M b The value of is M / 2, M / 2+1 or M / 2-1; if M is an odd number, M a The value of is (M+1) / 2 or (M-1) / 2, and the corresponding M b The value of is (M-1) / 2 or (M+1) / 2; the number r of the maximum array element spacing M satisfies NM-1≤r≤NM, and r is a positive integer; Step 2: Based on the hole-free MISC array design principle, the MISC array configuration is designed, including determining the number of array elements, the array element internal spacing distribution set, and the array element position distribution set.

6. The design method according to claim 5, characterized in that: In step 2, the MISC array configuration is designed as follows: For an array configuration with N elements, N>12, the maximum element spacing is defined as And M is an odd number, the internal spacing distribution set of the array element for: Where M s =(M+1) / 2, M h =(M-5) / 2, r = NM; the array configuration consists of 6 uniform linear arrays ULA, and the array element spacing of each ULA is 1, 3, M respectively. s -1, M, M s , 1, superscript M h , 2, r, 3, M h Indicates the number of repeated items corresponding to the array element spacing; Array element position distribution set for: Wherein, ULA1 to ULA6 represent six uniform linear arrays respectively, and IES represents the array element spacing.

7. The design method according to claim 6, characterized in that: The continuous degree of freedom of the array configuration uDOF = -2M 2 +2MN+7M-6.

8. The design method according to claim 6, characterized in that: The three weight functions ω(1), ω(2) and ω(3) used to characterize the mutual coupling effect between array elements in the array configuration are: ω(1)=M-5; ω(2) = M-7; Wherein, the weight function ω(l) represents the number of sensor pairs corresponding to the common array index, and the above formula shows that in this array configuration, the number of sensor pairs with a common array index of 1 is M-5; the number of sensor pairs with a common array index of 2 is M-7; when the number of array elements is 13≤N≤19, the number of sensor pairs with a common array index of 3 is 1; when the number of array elements is N≥20, the number of sensor pairs with a common array index of 3 is M-8.

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