Small broadband 3*3Nlen matrix integrated with filtering function

Abstract

The invention discloses a small broadband 3 * 3Nol matrix integrated with a filtering function. The small broadband 3 * 3Nol matrix comprises a filtering coupler, a filtering phase shifter, a port extension line and a port. The filtering coupler comprises a first filtering coupler, a second filtering coupler and a third filtering coupler; the first filtering coupler comprises a first upper-layer coupling four-wire, a first lower-layer coupling four-wire, a first short circuit pin, a first floor slot, a first parallel coupling wire, a first asymmetric coupling wire, a first capacitor, a first grounding probe and a first bonding pad; the first asymmetric coupling line comprises a first coupling line, a second coupling line, a third coupling line and a fourth coupling line; the first capacitor comprises a first shunt capacitor and a second shunt capacitor. According to the structure, a filtering coupler with any output phase difference and good out-of-band rejection performance is designed by cascading parallel coupling lines and connecting asymmetric open-circuit lines in four lines with a filtering characteristic, and the filtering characteristic and miniaturization design of a No matrix are realized.

Description

Technical Field

[0001] The invention relates to the field of microwave antennas, and in particular to a small broadband 3×3 Nolen matrix with integrated filtering function. Background Art

[0002] Multi-beam antennas can radiate multiple beams in different directions or different modes, and have the advantages of high communication efficiency and strong anti-interference, so they have been widely used in the field of mobile communications. The beamforming network is the core component of the multi-beam antenna, which can provide output signals with a certain amplitude and phase. When different input ports are stimulated, the multi-beam antenna will generate radiation beams with different directions in space.

[0003] The most commonly used beamforming network based on circuit structure is the Butler matrix, but the traditional Butler matrix can only achieve 2 N Input / output ports and cross junctions are required, so the overall structure is complex and the design flexibility is poor. In order to improve the flexibility of the design, a new type of beamforming network, the Nolen matrix, has been proposed in recent years. The Nolen matrix has an arbitrary number of input / output ports, and has the advantages of high transmission efficiency and simple structure (no cross junctions are required), so it has become a research hotspot. At present, the research on the Nolen matrix mainly focuses on broadband, miniaturization and adjustable phase, while there is little research on the Nolen matrix with filtering characteristics, and the filtering Nolen matrix that can adapt to broadband application scenarios is in a blank state of research. Therefore, it is of great significance to study the miniaturized broadband Nolen matrix with integrated filtering characteristics. Summary of the invention

[0004] According to the problems existing in the prior art, the present invention discloses a small broadband 3×3 Nolen matrix integrating filtering function, comprising: a filtering coupler, a filtering phase shifter, a port extension line and a port;

[0005] The filter coupler includes a first filter coupler, a second filter coupler and a third filter coupler; the first filter coupler includes a first upper layer coupling four wires, a first lower layer coupling four wires, a first short-circuit pin, a first floor groove, a first parallel coupling line, a first asymmetric coupling line, a first capacitor, a first grounding probe and a first pad; the first asymmetric coupling line includes a first coupling line, a second coupling line, a third coupling line and a fourth coupling line; the first capacitor includes a first parallel capacitor and a second parallel capacitor; the second filter coupler includes a second upper layer coupling four wires, a second lower layer coupling four wires, a second short-circuit pin, a second floor groove, a second parallel coupling line, a second an asymmetric coupling line, a second capacitor, a second grounding probe and a second pad; the second asymmetric coupling line includes a fifth coupling line, a sixth coupling line, a seventh coupling line and an eighth coupling line; the second capacitor includes a third parallel capacitor and a fourth parallel capacitor; the third filter coupler includes a third upper coupling four-wire, a third lower coupling four-wire, a third short-circuit pin, a third floor groove, a third parallel coupling line, a third asymmetric coupling line, a third capacitor, a third grounding probe and a third pad; the third asymmetric coupling line includes a ninth coupling line, a tenth coupling line, an eleventh coupling line and a twelfth coupling line; the third capacitor includes a fifth parallel capacitor and a sixth parallel capacitor.

[0006] The filter phase shifter includes a first filter phase shifter and a second filter phase shifter; the first filter phase shifter includes a first upper layer parallel coupling line, a first lower layer parallel coupling line, a fourth short-circuit pin, a fourth floor groove, a fourth ground probe and a fourth parallel coupling line.

[0007] The port extension line includes a first input port extension line, a second input port extension line, a third input port extension line, a first output port extension line, a second output port extension line and a third output port extension line; the first input port extension line includes a first transmission line, a fifth parallel coupling line, a first open line and a second transmission line; the first output port extension line includes a third transmission line, a fourth transmission line, a sixth parallel coupling line, a first short-circuit line and a second short-circuit line.

[0008] The ports include a first input port, a second input port, a third input port, a first output port, a second output port, and a third output port.

[0009] The first filter coupler is cascaded with the first parallel coupling line, the second filter coupler is cascaded with the second parallel coupling line, and the third filter coupler is cascaded with the third parallel coupling line; the first input port extension line is connected to the upper left end of the first filter coupler, and the upper right end of the first filter coupler is connected to the first output port extension line; the second input port extension line is connected to the upper left end of the second filter coupler, the upper right end of the second filter coupler is connected to the left end of the second filter phase shifter, the right end of the second filter phase shifter is connected to the lower left end of the first parallel coupling line, the lower right end of the first parallel coupling line is connected to the upper left end of the third filter coupler, and the upper right end of the third filter coupler is connected to the second output port extension line; the third input port extension line is connected to the lower left end of the second parallel coupling line, the lower right end of the second parallel coupling line is connected to the left end of the first filter phase shifter, the right end of the first filter phase shifter is connected to the lower left end of the third parallel coupling line, and the lower right end of the third parallel coupling line is connected to the third output port extension line.

[0010] The first upper layer coupling four wires are connected to the first lower layer coupling four wires through the first short-circuit pin, the first lower layer coupling four wires are located in the first floor groove and are not connected to the floor; the lower end of the first coupling wire is connected to the lower end of the second coupling wire, the upper end of the second coupling wire is connected to the upper left end of the first upper layer coupling four wires, and the first parallel capacitor is connected in parallel to the middle position of the first coupling wire; the lower end of the third coupling wire (1163) is connected to the lower end of the fourth coupling wire, the upper end of the third coupling wire is connected to the upper right end of the first upper layer coupling four wires, and the second parallel capacitor is connected in parallel to the middle position of the fourth coupling wire; the first parallel capacitor and the second parallel capacitor are connected to the first pad and connected to the floor through the first grounding probe; the second upper layer coupling four wires are connected to the second lower layer coupling four wires through the second short-circuit pin, the second lower layer coupling four wires are located in the second floor groove and are not connected to the floor; the lower end of the fifth coupling wire is connected to the lower end of the sixth coupling wire, the upper end of the sixth coupling wire is connected to the upper left end of the second upper layer coupling four wires, and the third parallel capacitor is connected in parallel to the first The middle position of the fifth coupling line; the lower end of the seventh coupling line is connected to the lower end of the eighth coupling line, the upper end of the seventh coupling line is connected to the upper right end of the second upper layer coupling four-wire, and the fourth parallel capacitor is connected in parallel to the middle position of the eighth coupling line; the third parallel capacitor and the fourth parallel capacitor are connected to the second pad, and are connected to the floor through the second grounding probe; the third upper layer coupling four-wire is connected to the third lower layer coupling four-wire through the third short-circuit pin, and the third lower layer coupling four-wire is located in the third floor groove and is not connected to the floor; the lower end of the ninth coupling line is connected to the lower end of the tenth coupling line, the upper end of the tenth coupling line is connected to the upper left end of the third upper layer coupling four-wire, and the fifth parallel capacitor is connected in parallel to the middle position of the ninth coupling line; the lower end of the eleventh coupling line is connected to the lower end of the twelfth coupling line, the upper end of the eleventh coupling line is connected to the upper right end of the third upper layer coupling four-wire, and the sixth parallel capacitor is connected in parallel to the middle position of the twelfth coupling line; the fifth parallel capacitor and the sixth parallel capacitor are connected to the third pad, and are connected to the floor through the third grounding probe.

[0011] The first upper layer parallel coupling line is connected to the first lower layer parallel coupling line through a fourth short-circuit pin, the first lower layer parallel coupling line is located in a fourth floor groove and is not connected to the floor; one diagonal of the first upper layer parallel coupling line is connected to the floor through a fourth grounding probe; the right end of the first upper layer parallel coupling line is connected to the left end of the fourth parallel coupling line.

[0012] The right end of the first transmission line is connected to the upper left end of the fifth parallel coupling line, the upper right end of the fifth parallel coupling line is connected to the second transmission line, the first open line is connected in parallel between the lower ends of the fifth parallel coupling lines; a diagonal open circuit of the sixth parallel coupling line is connected in parallel to both ends of the third transmission line; the first short-circuit line and the second short-circuit line are respectively connected in parallel to both ends of the third transmission line, and the right end of the third transmission line is connected to the left end of the fourth transmission line.

[0013] Furthermore, by adjusting the length of the first parallel coupling line, any output phase difference of the first filter coupler can be achieved, by adjusting the length of the second parallel coupling line, any output phase difference of the second filter coupler can be achieved, and by adjusting the length of the third parallel coupling line, any output phase difference of the third filter coupler can be achieved, thereby effectively reducing the overall size of the Nolen matrix.

[0014] Furthermore, by adjusting the impedance ratio of the first coupling line to the second coupling line, and the impedance ratio of the fourth coupling line to the third coupling line, a flat output phase difference of the first filter coupler within a wide bandwidth can be achieved; by adjusting the impedance ratio of the fifth coupling line to the sixth coupling line, and the impedance ratio of the eighth coupling line to the seventh coupling line, a flat output phase difference of the second filter coupler within a wide bandwidth can be achieved; by adjusting the impedance ratio of the ninth coupling line to the tenth coupling line, and the impedance ratio of the twelfth coupling line to the eleventh coupling line, a flat output phase difference of the third filter coupler within a wide bandwidth can be achieved.

[0015] Furthermore, by adjusting the impedance values ​​of the first short-circuit line and the second short-circuit line, a flat phase difference between the first output port and the second output port within a wide bandwidth can be achieved when the first input port is excited; by adjusting the phase relationship between the first filter phase shifter and the second filter phase shifter, a flat phase difference between the first output port and the second output port, and between the second output port and the third output port within a wide bandwidth can be achieved when the second input port or the third input port is excited.

[0016] Furthermore, by adjusting the impedance values ​​of the third transmission line and the sixth parallel coupling line, a flat amplitude distribution of the first output port, the second output port and the third output port within a wide bandwidth can be achieved when the first input port is excited; by adjusting the impedance values ​​of the first filter phase shifter and the second filter phase shifter, a flat amplitude distribution of the first output port, the second output port and the third output port within a wide bandwidth can be achieved when the second input port or the third input port is excited.

[0017] Furthermore, good output filtering characteristics can be achieved by adjusting the impedance ratio of the first coupling line to the second coupling line, the impedance ratio of the fourth coupling line to the third coupling line, the impedance ratio of the fifth coupling line to the sixth coupling line, the impedance ratio of the eighth coupling line to the seventh coupling line, the impedance ratio of the ninth coupling line to the tenth coupling line, and the impedance ratio of the twelfth coupling line to the eleventh coupling line.

[0018] Furthermore, the parameters of the second filter coupler are the same as those of the third filter coupler, and different from those of the first filter coupler; the impedances of the second input port extension line, the third input port extension line, the second output port extension line and the third output port extension line are all 50 ohms.

[0019] The electrical lengths of the first upper parallel coupling line, the first lower parallel coupling line, the fourth parallel coupling line, the second filter phase shifter, the third transmission line, the sixth parallel coupling line, the first short-circuit line and the second short-circuit line are all 90°.

[0020] Due to the adoption of the above technical scheme, a small broadband 3×3 Nolen matrix with integrated filtering function proposed by the present invention has the following advantages: (1) by cascading parallel coupled lines and paralleling asymmetric open lines on four lines with filtering characteristics, a filter coupler with arbitrary output phase difference and good out-of-band suppression performance is designed, thereby realizing the filtering characteristics and miniaturization design of the Nolen matrix; (2) by adopting a four-line coupling structure with broadband characteristics, the bandwidth of the designed Nolen matrix can reach more than 50%, and the amplitude error between the output ports within the band is small; (3) by adopting a filtering phase shifter, the phase of the 3×3 Nolen matrix is ​​compensated, thereby obtaining a flat phase characteristic within a broadband range and further improving the filtering characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 It is a schematic diagram of the structure of a small broadband 3×3 Nolen matrix of the fusion filtering function of the present invention;

[0023] Figure 2 It is a schematic diagram of the structure of the first / second / third filter coupler of the small broadband 3×3 Nolen matrix with integrated filtering function according to the present invention;

[0024] Figure 3It is a schematic diagram of the structure of the first filter phase shifter of the small broadband 3×3 Nolen matrix with integrated filtering function according to the present invention;

[0025] Figure 4 This is a graph of S-parameter results when the first input port of the small broadband 3×3 Nolen matrix with fused filtering function described in the present invention is excited;

[0026] Figure 5 This is a graph of S-parameter results when the second input port of the small broadband 3×3 Nolen matrix with fused filtering function described in the present invention is excited;

[0027] Figure 6 This is a graph of S-parameter results when the third input port of the small broadband 3×3 Nolen matrix with fused filtering function described in the present invention is excited;

[0028] Figure 7 It is a result diagram of the isolation between the input ports of the small broadband 3×3 Nolen matrix with fused filtering function described in the present invention;

[0029] Figure 8 It is a result diagram of the phase difference between the output ports when different input ports of the small broadband 3×3 Nolen matrix with fusion filtering function described in the present invention are stimulated.

[0030] 1. Filter coupler, 11. First filter coupler, 12. Second filter coupler, 13. Third filter coupler, 111. First upper layer coupling four wires, 112. First lower layer coupling four wires, 113. First shorting pin, 114. First floor groove, 115. First parallel coupling line, 116. First asymmetric coupling line, 117. First capacitor, 118. First ground probe, 119. First pad, 1161. First coupling line, 1162. Second coupling line, 1163. Third coupling line, 1164. Fourth coupling line, 1171. First parallel capacitor, 1172. Second parallel capacitor, 121. Second upper layer coupling four wires, 122. Second lower layer coupling four wires, 123. Second shorting pin, 124. Second floor groove, 125. Second parallel coupling line, 126. Second an asymmetric coupling line, 127, a second capacitor, 128, a second grounding probe, 129, a second pad, 1261, a fifth coupling line, 1262, a sixth coupling line, 1263, a seventh coupling line, 1264, an eighth coupling line, 1271, a third parallel capacitor, 1272, a fourth parallel capacitor, 131, a third upper coupling four-wire, 132, a third lower coupling four-wire, 133, a third short-circuit pin, 134, a third floor groove, 135, a third parallel coupling line, 136, a third asymmetric coupling line, 137, a third capacitor, 138, a third grounding probe, 139, a third pad, 1361, a ninth coupling line, 1362, a tenth coupling line, 1363, an eleventh coupling line, 1364 a twelfth coupling line, 1371, a fifth parallel capacitor, 1372, a sixth parallel capacitor;

[0031] 2. filter phase shifter, 21. first filter phase shifter, 22. second filter phase shifter, 211. first upper layer parallel coupling line, 212. first lower layer parallel coupling line, 213. fourth shorting pin, 214. fourth floor slot, 215. fourth grounding probe, 216. fourth parallel coupling line;

[0032] 3, port extension line, 31, first input port extension line, 32, second input port extension line, 33, third input port extension line, 34, first output port extension line, 35, second output port extension line, 36, third output port extension line, 311, first transmission line, 312, fifth parallel coupled line, 313, first open line, 314, second transmission line, 341, third transmission line, 342, fourth transmission line, 343, sixth parallel coupled line, 344, first short line, 345, second short line;

[0033] 4. Port, 41: first input port, 42: second input port, 43: third input port, 44: first output port, 45: second output port, 46: third output port; DETAILED DESCRIPTION

[0034] In order to make the technical solutions and advantages of the present invention more clear, the technical solutions in the embodiments of the present invention are clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention:

[0035] The technical indicators used in this embodiment are as follows:

[0036] Frequency range: 2.6GHz~4.4GHz;

[0037] Return loss:>10dB;

[0038] Isolation:>10dB;

[0039] Out-of-band suppression: >15dB;

[0040] Output port amplitude value: -4.77±0.5dB;

[0041] Phase difference between output ports when the first input port is excited: 120°±5°;

[0042] Phase difference between output ports when the second input port is excited: 0°±5°;

[0043] Phase difference between output ports when the third input port is excited: -120°±5°;

[0044] like Figure 1 and Figure 3 As shown, a small broadband 3×3 Nolen matrix with integrated filtering function includes: a filter coupler 1, a filter phase shifter 2, a port extension line 3 and a port 4;

[0045] The filter coupler 1 includes a first filter coupler 11, a second filter coupler 12 and a third filter coupler 13; the first filter coupler 11 includes a first upper layer coupling four wires 111, a first lower layer coupling four wires 112, a first shorting needle 113, a first floor groove 114, a first parallel coupling line 115, a first asymmetric coupling line 116, a first capacitor 117, a first grounding probe 118 and a first pad 119; the first asymmetric coupling line 116 includes a first coupling line 1161, a second coupling line 1162, a third coupling line 1163 and a fourth coupling line 1164; the first capacitor 117 includes a first parallel capacitor 1171 and a second parallel capacitor 1172; the second filter coupler 12 includes a second upper layer coupling four wires 121, a second lower layer coupling four wires 122, a second shorting needle 123, a second floor groove 124, a second parallel coupling line 125, a second asymmetric coupling line 126 , a second capacitor 127, a second grounding probe 128 and a second pad 129; the second asymmetric coupling line 126 includes a fifth coupling line 1261, a sixth coupling line 1262, a seventh coupling line 1263 and an eighth coupling line 1264; the second capacitor 127 includes a third parallel capacitor 1271 and a fourth parallel capacitor 1272; the third filter coupler 13 includes a third upper layer coupling four-wire 131, a third lower layer coupling four-wire 132, a third short-circuit pin 133, a third floor groove 134, a third parallel coupling line 135, a third asymmetric coupling line 136, a third capacitor 137, a third grounding probe 138 and a third pad 139; the third asymmetric coupling line 136 includes a ninth coupling line 1361, a tenth coupling line 1362, an eleventh coupling line 1363 and a twelfth coupling line 1364; the third capacitor 137 includes a fifth parallel capacitor 1371 and a sixth parallel capacitor 1372;

[0046] The filter phase shifter 2 includes a first filter phase shifter 21 and a second filter phase shifter 22; the first filter phase shifter 21 includes a first upper layer parallel coupling line 211, a first lower layer parallel coupling line 212, a fourth short-circuit pin 213, a fourth floor groove 214, a fourth grounding probe 215 and a fourth parallel coupling line 216;

[0047] The port extension line 3 includes a first input port extension line 31, a second input port extension line 32, a third input port extension line 33, a first output port extension line 34, a second output port extension line 35 and a third output port extension line 36; the first input port extension line 31 includes a first transmission line 311, a fifth parallel coupling line 312, a first open line 313 and a second transmission line 314; the first output port extension line 34 includes a third transmission line 341, a fourth transmission line 342, a sixth parallel coupling line 343, a first short-circuit line 344 and a second short-circuit line 345;

[0048] The port 4 includes a first input port 41, a second input port 42, a third input port 43, a first output port 44, a second output port 45 and a third output port 46;

[0049] The first filter coupler 11 is cascaded with the first parallel coupling line 115, the second filter coupler 12 is cascaded with the second parallel coupling line 125, and the third filter coupler 13 is cascaded with the third parallel coupling line 135; the first input port extension line 31 is connected to the upper left end of the first filter coupler 11, and the upper right end of the first filter coupler 11 is connected to the first output port extension line 34; the second input port extension line 32 is connected to the upper left end of the second filter coupler 12, and the upper right end of the second filter coupler 12 is connected to the left end of the second filter phase shifter 22, and the upper right end of the second filter phase shifter 22 is connected to the left end of the second filter phase shifter 22. The right end is connected to the lower left end of the first parallel coupling line 115, the lower right end of the first parallel coupling line 115 is connected to the upper left end of the third filter coupler 13, and the upper right end of the third filter coupler 13 is connected to the second output port extension line 35; the third input port extension line 33 is connected to the lower left end of the second parallel coupling line 125, the lower right end of the second parallel coupling line 125 is connected to the left end of the first filter phase shifter 21, the right end of the first filter phase shifter 21 is connected to the lower left end of the third parallel coupling line 135, and the lower right end of the third parallel coupling line 135 is connected to the third output port extension line 36;

[0050] The first upper layer coupling four wires 111 are connected to the first lower layer coupling four wires 112 through the first short-circuit pin 113. The first lower layer coupling four wires 112 are located in the first floor groove 114 and are not connected to the floor. The lower end of the first coupling wire 1161 is connected to the lower end of the second coupling wire 1162, and the upper end of the second coupling wire 1162 is connected to the upper left end of the first upper layer coupling four wires 111. The first parallel capacitor 1171 is connected in parallel to the middle position of the first coupling wire 1161. The lower end of the third coupling wire 1163 is connected to the lower end of the fourth coupling wire 1164, and the upper end of the third coupling wire 1163 is connected to the upper right end of the first upper layer coupling four wires 111. The second parallel capacitor 1171 is connected in parallel to the middle position of the first coupling wire 1161. The capacitor 1172 is connected in parallel at the middle position of the fourth coupling line 1164; the first parallel capacitor 1171 and the second parallel capacitor 1172 are connected to the first pad 119, and are connected to the floor through the first ground probe 118; the second upper layer coupling four wires 121 are connected to the second lower layer coupling four wires 122 through the second short-circuit pin 123, and the second lower layer coupling four wires 122 are located in the second floor groove 124 and are not connected to the floor; the lower end of the fifth coupling line 1261 is connected to the lower end of the sixth coupling line 1262, and the upper end of the sixth coupling line 1262 is connected to the upper left end of the second upper layer coupling four wires 121, and the third parallel capacitor 1271 is connected in parallel to the fifth coupling line 126 1; the lower end of the seventh coupling line 1263 is connected to the lower end of the eighth coupling line 1264, the upper end of the seventh coupling line 1263 is connected to the upper right end of the second upper layer coupling four-wire 121, and the fourth parallel capacitor 1272 is connected in parallel to the middle position of the eighth coupling line 1264; the third parallel capacitor 1271 and the fourth parallel capacitor 1272 are connected to the second pad 129, and are connected to the floor through the second grounding probe 128; the third upper layer coupling four-wire 131 is connected to the third lower layer coupling four-wire 132 through the third short-circuit pin 133, and the third lower layer coupling four-wire 132 is located in the third floor groove 134 and is not connected to the floor; the ninth coupling line 136 1 is connected to the lower end of the tenth coupling line 1362, the upper end of the tenth coupling line 1362 is connected to the upper left end of the third upper layer coupling four-wire 131, and the fifth parallel capacitor 1371 is connected in parallel to the middle position of the ninth coupling line 1361; the lower end of the eleventh coupling line 1363 is connected to the lower end of the twelfth coupling line 1364, the upper end of the eleventh coupling line 1363 is connected to the upper right end of the third upper layer coupling four-wire 131, and the sixth parallel capacitor 1372 is connected in parallel to the middle position of the twelfth coupling line 1364; the fifth parallel capacitor 1371 and the sixth parallel capacitor 1372 are connected to the third pad 139, and are connected to the floor through the third grounding probe 138;

[0051] The first upper layer parallel coupling line 211 is connected to the first lower layer parallel coupling line 212 through a fourth short-circuit pin 213, and the first lower layer parallel coupling line 212 is located in a fourth floor groove 214 and is not connected to the floor; one diagonal of the first upper layer parallel coupling line 211 is connected to the floor through a fourth grounding probe 215; the right end of the first upper layer parallel coupling line 211 is connected to the left end of the fourth parallel coupling line 216;

[0052] The right end of the first transmission line 311 is connected to the upper left end of the fifth parallel coupling line 312, the upper right end of the fifth parallel coupling line 312 is connected to the second transmission line 314, the first open line 313 is connected in parallel between the lower ends of the fifth parallel coupling line 312; a diagonal open circuit of the sixth parallel coupling line 343 is connected in parallel to the two ends of the third transmission line 341; the first short-circuit line 344 and the second short-circuit line 345 are respectively connected in parallel to the two ends of the third transmission line 341, and the right end of the third transmission line 341 is connected to the left end of the fourth transmission line 342;

[0053] By adjusting the length of the first parallel coupling line 115, any output phase difference of the first filter coupler 11 can be achieved, by adjusting the length of the second parallel coupling line 125, any output phase difference of the second filter coupler 12 can be achieved, and by adjusting the length of the third parallel coupling line 135, any output phase difference of the third filter coupler 13 can be achieved, which effectively reduces the overall size of the Nolen matrix;

[0054] By adjusting the impedance ratio of the first coupling line 1161 to the second coupling line 1162, and the impedance ratio of the fourth coupling line 1164 to the third coupling line 1163, a flat output phase difference of the first filter coupler 11 can be achieved within a wide frequency band; by adjusting the impedance ratio of the fifth coupling line 1261 to the sixth coupling line 1262, and the impedance ratio of the eighth coupling line 1264 to the seventh coupling line 1263, a flat output phase difference of the second filter coupler 12 can be achieved within a wide frequency band; by adjusting the impedance ratio of the ninth coupling line 1361 to the tenth coupling line 1362, and the impedance ratio of the twelfth coupling line 1364 to the eleventh coupling line 1363, a flat output phase difference of the third filter coupler 13 can be achieved within a wide frequency band;

[0055] By adjusting the impedance values ​​of the first short-circuit line 344 and the second short-circuit line 345, a flat phase difference between the first output port 44 and the second output port 45 within a wide frequency band can be achieved when the first input port 41 is excited; by adjusting the phase relationship between the first filter phase shifter 21 and the second filter phase shifter 22, a flat phase difference between the first output port 44 and the second output port 45, and between the second output port 45 and the third output port 46 within a wide frequency band can be achieved when the second input port 42 or the third input port 43 is excited;

[0056] By adjusting the impedance values ​​of the third transmission line 341 and the sixth parallel coupling line 343, it is possible to achieve a flat amplitude distribution of the first output port 44, the second output port 45 and the third output port 46 within a wide frequency band when the first input port 41 is excited; by adjusting the impedance values ​​of the first filtering phase shifter 21 and the second filtering phase shifter 22, it is possible to achieve a flat amplitude distribution of the first output port 44, the second output port 45 and the third output port 46 within a wide frequency band when the second input port 42 or the third input port 43 is excited;

[0057] Good output filtering characteristics can be achieved by adjusting the impedance ratio of the first coupling line 1161 to the second coupling line 1162, the impedance ratio of the fourth coupling line 1164 to the third coupling line 1163, the impedance ratio of the fifth coupling line 1261 to the sixth coupling line 1262, the impedance ratio of the eighth coupling line 1264 to the seventh coupling line 1263, the impedance ratio of the ninth coupling line 1361 to the tenth coupling line 1362, and the impedance ratio of the twelfth coupling line 1364 to the eleventh coupling line 1363.

[0058] The parameters of the second filter coupler 12 and the third filter coupler 13 are the same, and the parameters of the first filter coupler 11 are different; the impedance of the second input port extension line 32, the third input port extension line 33, the second output port extension line 35 and the third output port extension line 36 are all 50 ohms;

[0059] The electrical lengths of the first upper layer parallel coupling line 211, the first lower layer parallel coupling line 212, the fourth parallel coupling line 216, the second filter phase shifter 22, the third transmission line 341, the sixth parallel coupling line 343, the first short-circuit line 344 and the second short-circuit line 345 are all 90°;

[0060] Specific embodiments of the present invention are described below.

[0061] The S parameter matrix of the first filter coupler 11 can be expressed as:

[0062]

[0063] The S parameter matrices of the second filter coupler 12 and the third filter coupler 13 can be expressed as:

[0064]

[0065] The S-parameters of the small broadband 3×3 Nolen matrix input-output relationship of the fusion filter function can be expressed as:

[0066]

[0067]

[0068] From the above formula, we can get that when different input ports are stimulated, the signal amplitudes at the output ports are equal, and the phase difference between the output ports is:

[0069] ∠S 41 -∠S 51 =∠S 51 -∠S 61 =120°

[0070] ∠S 42 -∠S 52 =∠S 52 -∠S 62 =0°

[0071] ∠S 43 -∠S 53 =∠S 53 -∠S 63 =-120°

[0072] Figure 4 The S parameter result diagram of the small broadband 3×3 Nolen matrix with fused filtering function proposed in the present invention when the first input port is excited is given. At the example center frequency of 3.5GHz, the input port return loss |S 11 | is -20.6dB. In the frequency range of 2.55~4.43GHz(53.7%) |S 11 |Less than -10dB. Transmission curve |S within the relative bandwidth greater than 50% (2.6~4.4GHz) 41 |、|S 51 | and |S 61 The amplitude fluctuation is less than 0.5dB, the 3-dB filtering bandwidth is 73.7%, and the out-of-band suppression is greater than 15dB.

[0073] Figure 5 The S parameter result diagram of the small broadband 3×3 Nolen matrix with fused filtering function proposed in the present invention when the second input port is excited is given. At the example center frequency of 3.5GHz, the input port return loss |S 22| is -12.3dB. In the frequency range of 2.09~4.95GHz(78.3%) |S 22 |Less than -10dB. Transmission curve |S within the relative bandwidth greater than 50% (2.6~4.4GHz) 42 |、|S 52 | and |S 62 The amplitude fluctuation is less than 0.5dB, the 3-dB filtering bandwidth is 81.7%, and the out-of-band suppression is greater than 15dB.

[0074] Figure 6 The S parameter result diagram of the small broadband 3×3 Nolen matrix with fused filtering function proposed in the present invention when the third input port is excited is given. At the example center frequency of 3.5GHz, the input port return loss |S 33 | is -16.8dB. In the frequency range of 2.6~5GHz(68.6%) |S 33 |Less than -10dB. Transmission curve |S within the relative bandwidth greater than 50% (2.6~4.4GHz) 43 |、|S 53 | and |S 63 The amplitude fluctuation of | is less than 0.5dB, the 3-dB filtering bandwidth is 84.3%, and the out-of-band suppression is greater than 15dB. The S parameter results meet the technical index requirements of the broadband filtering beamforming network, indicating that the beamforming network proposed in the present invention has good impedance matching and filtering characteristics in a wide frequency range.

[0075] Figure 7 The isolation results of the small broadband 3×3 Nolen matrix with fused filtering function proposed by the present invention are given. In the frequency range of 2.09~5.01GHz (83.4%), the isolation between each port is greater than -10dB. This shows that the input ports in the beamforming network proposed by the present invention are independent of each other in a wider frequency range and do not interfere with each other, and the input signal can be transmitted in a predetermined direction.

[0076] Figure 8 The result diagram of the phase difference between the output ports of the small broadband 3×3 Nolen matrix with fused filtering function proposed by the present invention when different input ports are excited is given. The phase error is less than ±5° within the relative bandwidth greater than 50% (2.6~4.4GHz). This shows that the output phase difference of the beamforming network proposed by the present invention has a high flatness characteristic.

[0077] The size of the small broadband 3×3 Nolen matrix of the fusion filter function proposed in the present invention is: 0.5λ g ×0.5λ g (λ gis the waveguide wavelength corresponding to the center frequency of 3.5 GHz), which shows that the beamforming network proposed in the present invention has the advantages of wide impedance bandwidth, wide passband bandwidth, good isolation between output ports, good out-of-band suppression performance, flat amplitude and phase difference between output ports, simple design and low cost while taking into account small size.

[0078] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A small broadband 3×3 Nolen matrix with integrated filtering function, characterized in that include: A filter coupler (1), a filter phase shifter (2), a port extension line (3) and a port (4); The filter coupler (1) comprises a first filter coupler (11), a second filter coupler (12) and a third filter coupler (13); the first filter coupler (11) comprises a first upper layer coupling four wires (111), a first lower layer coupling four wires (112), a first short-circuit pin (113), a first floor groove (114), a first parallel coupling line (115), a first asymmetric coupling line (116), a first capacitor (117), a first grounding probe (118) and a first pad (119); the first asymmetric coupling line ( The first coupling line (116) includes a first coupling line (1161), a second coupling line (1162), a third coupling line (1163) and a fourth coupling line (1164); the first capacitor (117) includes a first parallel capacitor (1171) and a second parallel capacitor (1172); the second filter coupler (12) includes a second upper layer coupling four wires (121), a second lower layer coupling four wires (122), a second short-circuit pin (123), a second floor groove (124), a second parallel coupling line (125), and a second asymmetric coupling line (126). , a second capacitor (127), a second grounding probe (128) and a second pad (129); the second asymmetric coupling line (126) includes a fifth coupling line (1261), a sixth coupling line (1262), a seventh coupling line (1263) and an eighth coupling line (1264); the second capacitor (127) includes a third parallel capacitor (1271) and a fourth parallel capacitor (1272); the third filter coupler (13) includes a third upper layer coupling four lines (131), a third lower layer coupling four lines (132), a third short circuit A third grounding probe (138) and a third pad (139); the third asymmetric coupling line (136) includes a ninth coupling line (1361), a tenth coupling line (1362), an eleventh coupling line (1363) and a twelfth coupling line (1364); the third capacitor (137) includes a fifth parallel capacitor (1371) and a sixth parallel capacitor (1372); The filter phase shifter (2) comprises a first filter phase shifter (21) and a second filter phase shifter (22); the first filter phase shifter (21) comprises a first upper layer parallel coupling line (211), a first lower layer parallel coupling line (212), a fourth short-circuit pin (213), a fourth floor groove (214), a fourth grounding probe (215) and a fourth parallel coupling line (216); The port extension line (3) comprises a first input port extension line (31), a second input port extension line (32), a third input port extension line (33), a first output port extension line (34), a second output port extension line (35) and a third output port extension line (36); the first input port extension line (31) comprises a first transmission line (311), a fifth parallel coupling line (312), a first open line (313) and a second transmission line (314); the first output port extension line (34) comprises a third transmission line (341), a fourth transmission line (342), a sixth parallel coupling line (343), a first short-circuit line (344) and a second short-circuit line (345); The port (4) comprises a first input port (41), a second input port (42), a third input port (43), a first output port (44), a second output port (45) and a third output port (46); The first filter coupler (11) is cascaded with the first parallel coupling line (115), the second filter coupler (12) is cascaded with the second parallel coupling line (125), and the third filter coupler (13) is cascaded with the third parallel coupling line (135); the first input port extension line (31) is connected to the upper left end of the first filter coupler (11), and the upper right end of the first filter coupler (11) is connected to the first output port extension line (34); the second input port extension line (32) is connected to the upper left end of the second filter coupler (12), and the upper right end of the second filter coupler (12) is connected to the left end of the second filter phase shifter (22); the second filter phase shifter (22) is connected to the left end of the second filter coupler (12); ) is connected to the lower left end of the first parallel coupling line (115), the lower right end of the first parallel coupling line (115) is connected to the upper left end of the third filter coupler (13), the upper right end of the third filter coupler (13) is connected to the second output port extension line (35); the third input port extension line (33) is connected to the lower left end of the second parallel coupling line (125), the lower right end of the second parallel coupling line (125) is connected to the left end of the first filter phase shifter (21), the right end of the first filter phase shifter (21) is connected to the lower left end of the third parallel coupling line (135), and the lower right end of the third parallel coupling line (135) is connected to the third output port extension line (36); The first upper layer coupling four wires (111) are connected to the first lower layer coupling four wires (112) through a first short-circuit pin (113); the first lower layer coupling four wires (112) are located in a first floor groove (114) and are not connected to the floor; the lower end of the first coupling wire (1161) is connected to the lower end of the second coupling wire (1162); the upper end of the second coupling wire (1162) is connected to the upper left end of the first upper layer coupling four wires (111); the first parallel capacitor (1171) is connected in parallel to the middle position of the first coupling wire (1161); the lower end of the third coupling wire (1163) is connected to the lower end of the fourth coupling wire (1164); the upper end of the third coupling wire (1163) is connected to the first upper layer coupling four wires (111); ), the second parallel capacitor (1172) is connected in parallel to the middle position of the fourth coupling line (1164); the first parallel capacitor (1171) and the second parallel capacitor (1172) are connected to the first pad (119), and are connected to the floor through the first grounding probe (118); the second upper layer coupling four wires (121) are connected to the second lower layer coupling four wires (122) through the second shorting pin (123), the second lower layer coupling four wires (122) are located in the second floor groove (124), and are not connected to the floor; the lower end of the fifth coupling line (1261) is connected to the lower end of the sixth coupling line (1262), and the upper end of the sixth coupling line (1262) is connected to the upper left corner of the second upper layer coupling four wires (121); The third parallel capacitor (1271) is connected in parallel to the middle position of the fifth coupling line (1261); the lower end of the seventh coupling line (1263) is connected to the lower end of the eighth coupling line (1264), the upper end of the seventh coupling line (1263) is connected to the upper right end of the second upper layer coupling four lines (121), and the fourth parallel capacitor (1272) is connected in parallel to the middle position of the eighth coupling line (1264); the third parallel capacitor (1271) and the fourth parallel capacitor (1272) are connected to the second pad (129), and are connected to the ground through the second grounding probe (128); the third upper layer coupling four lines (131) are connected to the third lower layer coupling four lines (132) through the third short-circuit pin (133), and the The third lower layer coupling four wires (132) are located in the third floor groove (134) and are not connected to the floor; the lower end of the ninth coupling wire (1361) is connected to the lower end of the tenth coupling wire (1362), the upper end of the tenth coupling wire (1362) is connected to the upper left end of the third upper layer coupling four wires (131), and the fifth parallel capacitor (1371) is connected in parallel to the middle position of the ninth coupling wire (1361); the lower end of the eleventh coupling wire (1363) is connected to the lower end of the twelfth coupling wire (1364), the upper end of the eleventh coupling wire (1363) is connected to the upper right end of the third upper layer coupling four wires (131), and the sixth parallel capacitor (1372) is connected in parallel to the middle position of the twelfth coupling wire (1364);The fifth parallel capacitor (1371) and the sixth parallel capacitor (1372) are connected to the third pad (139) and connected to the ground via the third ground probe (138); The first upper layer parallel coupling line (211) is connected to the first lower layer parallel coupling line (212) via a fourth short-circuit pin (213); the first lower layer parallel coupling line (212) is located in a fourth floor groove (214) and is not connected to the floor; one diagonal of the first upper layer parallel coupling line (211) is connected to the floor via a fourth grounding probe (215); the right end of the first upper layer parallel coupling line (211) is connected to the left end of the fourth parallel coupling line (216); The right end of the first transmission line (311) is connected to the upper left end of the fifth parallel coupling line (312), the upper right end of the fifth parallel coupling line (312) is connected to the second transmission line (314), the first open line (313) is connected in parallel between the lower ends of the fifth parallel coupling line (312); a diagonal open circuit of the sixth parallel coupling line (343) is connected in parallel to the two ends of the third transmission line (341); the first short-circuit line (344) and the second short-circuit line (345) are respectively connected in parallel to the two ends of the third transmission line (341), and the right end of the third transmission line (341) is connected to the left end of the fourth transmission line (342).

2. A small broadband 3×3 Nolen matrix with fused filtering function according to claim 1, characterized in that: By adjusting the length of the first parallel coupling line (115), the first filter coupler (11) is controlled to output an arbitrary phase difference; by adjusting the length of the second parallel coupling line (125), the second filter coupler (12) is controlled to output an arbitrary phase difference; and by adjusting the length of the third parallel coupling line (135), the third filter coupler (13) is controlled to output an arbitrary phase difference, thereby reducing the overall size of the Nolen matrix.

3. A small broadband 3×3 Nolen matrix with fused filtering function according to claim 1, characterized in that: The first filter coupler (11) is controlled to have a flat output phase difference within a wide frequency band by adjusting the impedance ratio between the first coupling line (1161) and the second coupling line (1162) and the impedance ratio between the fourth coupling line (1164) and the third coupling line (1163); the second filter coupler (12) is controlled to have a flat output phase difference within a wide frequency band by adjusting the impedance ratio between the fifth coupling line (1261) and the sixth coupling line (1262) and the impedance ratio between the eighth coupling line (1264) and the seventh coupling line (1263); the third filter coupler (13) is controlled to have a flat output phase difference within a wide frequency band by adjusting the impedance ratio between the ninth coupling line (1361) and the tenth coupling line (1362) and the impedance ratio between the twelfth coupling line (1364) and the eleventh coupling line (1363).

4. A small broadband 3×3 Nolen matrix with fused filtering function according to claim 1, characterized in that: By adjusting the impedance values ​​of the first short-circuit line (344) and the second short-circuit line (345), a flat phase difference between the first output port (44) and the second output port (45) can be achieved within a wide frequency band when the first input port (41) is excited; by adjusting the phase relationship between the first filter phase shifter (21) and the second filter phase shifter (22), a flat phase difference between the first output port (44) and the second output port (45), and between the second output port (45) and the third output port (46) can be achieved within a wide frequency band when the second input port (42) or the third input port (43) is excited.

5. A small broadband 3×3 Nolen matrix with integrated filtering function according to claim 1, characterized in that: By adjusting the impedance values ​​of the third transmission line (341) and the sixth parallel coupling line (343), a flat amplitude distribution of the first output port (44), the second output port (45) and the third output port (46) within a wide frequency band can be achieved when the first input port (41) is excited; by adjusting the impedance values ​​of the first filtering phase shifter (21) and the second filtering phase shifter (22), a flat amplitude distribution of the first output port (44), the second output port (45) and the third output port (46) within a wide frequency band can be achieved when the second input port (42) or the third input port (43) is excited.

6. A small broadband 3×3 Nolen matrix with integrated filtering function according to claim 1, characterized in that: The output stable filtering characteristics are controlled by adjusting the impedance ratio of the first coupling line (1161) and the second coupling line (1162), the impedance ratio of the fourth coupling line (1164) and the third coupling line (1163), the impedance ratio of the fifth coupling line (1261) and the sixth coupling line (1262), the impedance ratio of the eighth coupling line (1264) and the seventh coupling line (1263), the impedance ratio of the ninth coupling line (1361) and the tenth coupling line (1362), and the impedance ratio of the twelfth coupling line (1364) and the eleventh coupling line (1363).

7. A small broadband 3×3 Nolen matrix with integrated filtering function according to claim 1, characterized in that: The parameters of the second filter coupler (12) and the third filter coupler (13) are the same, and the parameters of the first filter coupler (11) are different; the impedances of the second input port extension line (32), the third input port extension line (33), the second output port extension line (35) and the third output port extension line (36) are all 50 ohms.

8. A small broadband 3×3 Nolen matrix with integrated filtering function according to claim 1, characterized in that: The electrical lengths of the first upper layer parallel coupling line (211), the first lower layer parallel coupling line (212), the fourth parallel coupling line (216), the second filter phase shifter (22), the third transmission line (341), the sixth parallel coupling line (343), the first short-circuit line (344) and the second short-circuit line (345) are all 90°.

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