Waveguide slot antenna and control method therefor

Abstract

Disclosed in the present invention are a waveguide slot antenna and a control method therefor. The antenna comprises a feed port layer, a slow-wave line layer, and a radiation slot layer which are stacked in sequence; the feed port layer is provided with a feed port for inputting electromagnetic waves or outputting electromagnetic waves; one end face of the slow-wave line layer facing the feed port layer is provided with a serpentine slow-wave cavity, one end of the serpentine slow-wave cavity is provided with a feed signal end, and the feed signal end is correspondingly connected to the feed port; a plurality of waveguide radiation slots are arranged at intervals in a serpentine channel of the serpentine slow-wave cavity; and a plurality of radiation cavity units having one-to-one correspondence to the waveguide radiation slots are arranged at intervals on one end face of the radiation slot layer facing the slow-wave line layer, a plurality of radiation slots are arranged at intervals in each radiation cavity unit, and one end of each radiation cavity unit is provided with a signal connection end correspondingly coupled to the waveguide radiation slot. The present invention can increase the antenna scanning angle, thereby meeting application scenarios requiring a large antenna scanning range.

Description

A waveguide slot antenna and its control method Technical Field

[0001] This invention relates to the field of antenna technology, and in particular to a waveguide slot antenna and its control method. Background Technology

[0002] A waveguide slot antenna is an antenna with slots cut into the wide or narrow walls of a waveguide, allowing electromagnetic waves propagating in the waveguide to radiate outwards through the slots. This type of antenna is commonly used in the microwave band and can be applied in fields such as communications, radar, and satellite communications.

[0003] Current waveguide slot antennas consist of a feed port layer, a waveguide power divider layer, and a radiating slot layer. The waveguide power divider layer has multiple first waveguide cavities on its end face near the feed port layer. These first waveguide cavities are located directly below the feed port and are used to receive electromagnetic waves transmitted from the feed port. These first waveguide cavities divide the input power into 16 equal parts sequentially in a 1:2, 2:4, 4:8, and 8:16 manner. Each part of the power signal is coupled to the radiating slot layer through its corresponding output port and radiated outwards through the slots in the radiating slot layer. However, while this waveguide power divider structure can improve gain and enable signal monitoring over longer distances, its scanning angle is narrow (approximately 3°), resulting in low adaptability. Increasing the scanning angle requires a larger operating frequency band, which is a significant limitation. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a waveguide slot antenna and its control method, which can improve the antenna scanning angle to adapt to applications with high antenna scanning angle requirements and has high adaptability.

[0005] To address the aforementioned technical problems, this invention provides a waveguide slot antenna, comprising a feed port layer, a slow wave line layer, and a radiating slot layer stacked sequentially. The feed port layer has a feed port for inputting or outputting electromagnetic waves. The slow wave line layer has a serpentine slow wave cavity on one end face facing the feed port layer, and a feed signal terminal is provided at one end of the serpentine slow wave cavity, which is correspondingly connected to the feed port. Multiple waveguide radiating slots are spaced apart in the serpentine channel of the serpentine slow wave cavity. Multiple radiating cavity units are spaced apart on one end face of the radiating slot layer facing the slow wave line layer, each radiating cavity unit corresponding to a waveguide radiating slot. Multiple radiating slots are spaced apart within each radiating cavity unit, and a signal connection terminal correspondingly coupled to a waveguide radiating slot is provided at one end of each radiating cavity unit.

[0006] As an improvement to the above scheme, each straight waveguide segment in the serpentine channel is provided with the waveguide radiation slot, and the serpentine channel is located below the feed signal end.

[0007] As an improvement to the above scheme, the centerline of the straight waveguide segment is staggered from the centerline of its corresponding waveguide radiation slot, and the centerlines of the multiple waveguide radiation slots have different offsets.

[0008] As an improvement to the above scheme, the cross-section of the straight waveguide segment includes a wide side dimension a and a narrow side dimension b. The ratio e = d / a of the offset d of the centerline of the waveguide radiation slot relative to the centerline of the straight waveguide segment to the wide side dimension a is 0 < e < 0.5. The equivalent conductivity of the waveguide radiation slot increases as the ratio e increases.

[0009] As an improvement to the above scheme, the wide side dimension a of the waveguide is 1.37mm≤a≤4mm, the narrow side dimension b of the waveguide is 0.5mm≤b≤3.6mm, and the offset d of the center line of the waveguide radiation slot relative to the center line of the straight waveguide segment is 0.005mm≤d≤1.8mm.

[0010] As an improvement to the above scheme, the radiation cavity unit has a plurality of radiation slots spaced upward along the signal connection end, and two adjacent radiation slots are staggered and arranged on both sides of the vertical center line of the radiation cavity unit.

[0011] As an improvement to the above scheme, a coupling layer is provided between the feed port layer and the slow wave line layer. The coupling layer is provided with a coupling port corresponding to the feed port, and the coupling port is connected to the feed port and the feed signal terminal respectively.

[0012] As an improvement to the above scheme, the other end of the serpentine slow wave cavity is provided with a signal discharge port, and both the power supply port layer and the coupling layer are provided with discharge ports corresponding to and connected to the signal discharge port.

[0013] As an improvement to the above scheme, the end of the radiation cavity unit away from the signal connection terminal is provided with a first vent hole, and the feed port layer, the slow wave line layer and the coupling layer are all provided with second vent holes that correspond one-to-one with the first vent hole.

[0014] This invention also provides a waveguide slot antenna control method, applied to the waveguide slot antenna as described above. The method includes the following steps: acquiring an electromagnetic wave signal of a preset frequency and a control operation command; when the control operation command is the preset operation command, transmitting the electromagnetic wave signal to the feed port in the feed port layer, and transmitting it through the feed port to the feed signal terminal on the slow wave line layer; the electromagnetic wave signal is transmitted along the serpentine channel of the serpentine slow wave cavity through the feed signal terminal; when the electromagnetic wave signal passes through the waveguide radiation slots in the serpentine channel in sequence, the electromagnetic wave signal will be coupled to the signal connection terminal in the corresponding radiation cavity unit in sequence by the waveguide radiation slots; the electromagnetic wave signal is transmitted along the channel of the radiation cavity unit through the signal connection terminal; when the electromagnetic wave signal passes through the radiation slots in sequence, the radiation slots radiate the electromagnetic wave signal outward.

[0015] The beneficial effects of implementing this invention are as follows:

[0016] The present invention has a simple structure, consisting of multiple stacked layered plates, which facilitates production, processing and installation. The constructed slow-wave line structure can improve the antenna gain, and the scanning angle of the antenna can be increased by adjusting the operating frequency within a limited operating frequency band, so as to adapt to applications with high requirements for antenna scanning angle, and has high adaptability. Attached Figure Description

[0017] Figure 1 is an exploded structural diagram of the waveguide slot antenna of the present invention;

[0018] Figure 2 is a schematic diagram of the reverse structure of the slow wave line layer of the present invention;

[0019] Figure 3 is a schematic diagram of the front structure of the slow wave line layer of the present invention;

[0020] Figure 4 is a schematic diagram of the reverse structure of the radial slot layer of the present invention;

[0021] Figure 5 is a schematic diagram of the front structure of the radiation slot layer of the present invention;

[0022] Figure 6 is a schematic diagram of the front structure of the power supply port layer of the present invention;

[0023] Figure 7 is a schematic diagram of the front structure of the coupling layer of the present invention;

[0024] Figure 8 is a flowchart of the waveguide slot antenna control method of the present invention;

[0025] Figure 9 is a partial structural schematic diagram of the straight waveguide section of the present invention;

[0026] Figure 10 is a graph showing the offset of the waveguide radiation slot of the present invention versus the equivalent conductivity.

[0027] Figure 11 is a normalized electromagnetic wave pattern of Embodiment 1 of the serpentine slow wave plate of the present invention;

[0028] Figure 12 is a normalized electromagnetic wave pattern of Embodiment 2 of the serpentine slow wave plate of the present invention;

[0029] Figure 13 is a normalized electromagnetic wave pattern of Embodiment 3 of the serpentine slow wave plate of the present invention;

[0030] Figure 14 is a normalized electromagnetic wave pattern of Embodiment 4 of the serpentine slow wave plate of the present invention.

[0031] Figure 15 is the normalized radiation pattern of the electromagnetic wave of Comparative Example 1 of the serpentine slow wave plate of the present invention.

[0032] Figure 16 is the normalized radiation pattern of the electromagnetic wave of Comparative Example 2 of the serpentine slow wave plate of the present invention. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings.

[0034] As shown in Figures 1 to 6, a specific embodiment of the present invention provides a waveguide slot antenna, comprising a feed port layer 1, a slow wave line layer 2, and a radiation slot layer 3 stacked sequentially, forming a series-fed frequency-sweep array antenna structure. The feed port layer 1 is provided with a feed port 11 for inputting or outputting electromagnetic waves, and the feed port 11 can be fed via a transmission line, waveguide, or resonant cavity. The slow wave line layer 2 has a serpentine slow wave cavity 21 on one end facing the feed port layer 1, and a feed signal terminal 22 at one end of the serpentine slow wave cavity 21. The feed signal terminal 22 is connected to the feed port 11 to realize electromagnetic wave transmission; multiple waveguide radiation slots 24 are spaced apart in the serpentine channel 23 of the serpentine slow wave cavity 21. The radiation slot layer 3 has multiple radiation cavity units 31 spaced apart on one end face facing the slow wave line layer 2. Each radiation cavity unit 31 is arranged in a one-to-one correspondence with a waveguide radiation slot 24, that is, each waveguide radiation slot 24 is equipped with a radiation cavity unit 31. Multiple radiation slots 32 are spaced apart inside each radiation cavity unit 31. One end of each radiation cavity unit 31 is provided with a signal connection terminal 33 that is coupled to the waveguide radiation slot 24 to realize electromagnetic wave transmission.

[0035] When the antenna transmits a signal, the external antenna control device connects to the feed port 11 and sends a signal. The electromagnetic wave is transmitted through the feed port 11 to the feed signal terminal 22 on the slow wave line layer 2 and propagates along the serpentine channel 23 of the serpentine slow wave cavity 21. When the electromagnetic wave flows through each waveguide radiation slot 24, part of the electromagnetic wave signal is coupled to the corresponding signal connection terminal 33 through the waveguide radiation slot 24. The electromagnetic wave flows through the signal connection terminal 33 in the radiation cavity unit 31 and is emitted externally through multiple radiation slots 32 in the radiation cavity unit 31. Conversely, when the antenna receives a signal, it receives the electromagnetic wave through the radiation cavity unit 31, and then the electromagnetic wave is transmitted sequentially to the feed port 11 in the opposite direction, and finally transmitted to the antenna control device.

[0036] Specifically, the serpentine slow-wave line structure of this invention is fed by a series-fed frequency-scanning array. This serpentine slow-wave line structure allows for the pointing of the main beam of the antenna array pattern. Within the limited operating frequency band of the antenna array, the offset angle (i.e., the scanning angle) can be increased by adjusting the feed frequency. This allows it to adapt to applications with high antenna scanning angle requirements without requiring a large input operating frequency band, demonstrating high adaptability. Furthermore, this invention is constructed from multiple stacked layered structures, facilitating manufacturing and installation. Specifically, this invention achieves a scanning angle of up to 16° in the 79GHz-81GHz frequency band, meeting the corresponding antenna scanning angle requirements of various applications.

[0037] Specifically, as shown in Figures 2 and 4, the serpentine channel 23 includes several straight waveguide segments 231 and connecting waveguide segments 232. A gap is left between adjacent straight waveguide segments 231 to separate them and prevent signal interference. Adjacent straight waveguide segments 231 are connected by the connecting waveguide segments 232 to construct a slow waveline structure. Each straight waveguide segment 231 and its adjacent connecting waveguide segment 232 constitute a waveguide unit.

[0038] Each straight waveguide segment 231 in the serpentine channel 23 is provided with a waveguide radiation slot 24, and the serpentine channel 23 is located below the feed signal terminal 22. The radiating cavity unit 31 has at least one radiation slot 32 corresponding to the region of the serpentine channel 23, and this radiation slot 32 is close to the signal connection terminal 33. In actual operation, electromagnetic waves flowing through the straight waveguide segment 231 are coupled to the signal connection terminal 33 of the radiating cavity unit 31 via the waveguide radiation slot 24, so that the electromagnetic waves are emitted outward through the radiating cavity unit 31; conversely, electromagnetic waves received by the radiating cavity unit 31 are also coupled into the serpentine channel 23 and flow along the serpentine channel 23 towards the feed signal terminal 22. Preferably, each connecting waveguide segment 232 in the serpentine channel 23 is a 180-degree circular arc connecting waveguide segment, which can correspondingly reduce the voltage standing wave ratio (VSWR) of the serpentine waveguide, and correspondingly increase the antenna gain and reduce dissipation, thereby improving the stability of the antenna circuit. The shape of the connecting waveguide segment 232 is not limited to this; it can also be a rectangular connecting waveguide segment or a semi-circular or semi-rectangular connecting waveguide segment, etc.

[0039] Preferably, as shown in Figures 4 and 5, the radiation cavity unit 31 has a plurality of radiation slots 32 arranged at intervals along the signal connection end 33, and two adjacent radiation slots 32 are staggered on both sides of the vertical center line of the radiation cavity unit 31 to improve the radiation and reception effect of electromagnetic waves.

[0040] Preferably, as shown in Figures 1 and 7, a coupling layer 4 is provided between the feed port layer 1 and the slow wave line layer 2. The coupling layer 4 is provided with a coupling port 41 corresponding to the feed port 11. The coupling port 41 is connected to the feed port 11 and the feed signal terminal 22 respectively to realize the coupled transmission of electromagnetic waves.

[0041] Further, as shown in Figures 2, 3, 6, and 7, the other end of the serpentine slow-wave cavity 21 is provided with a signal discharge port 25, and both the feed port layer 1 and the coupling layer 4 are provided with discharge ports 5 corresponding to the signal discharge port 25. When the antenna transmits electromagnetic waves, the electromagnetic waves will flow into the serpentine channel 23 through the feed signal end 22. On the one hand, the electromagnetic waves are coupled to the radiation cavity unit 31 through the waveguide radiation gap 24 of the serpentine channel 23, realizing the outward radiation of the electromagnetic valve. On the other hand, the excess or excessive electromagnetic wave energy in the serpentine channel 23 is discharged outward through the discharge port 5 of the feed port layer 1 through the signal discharge port 25, and finally received by the corresponding external receiving device.

[0042] Further, as shown in Figures 2, 3, 4, 6, and 7, the end of the radiating cavity unit 31 furthest from the signal connection terminal 33 is provided with a first venting hole 34. The feed port layer 1, the slow wave line layer 2, and the coupling layer 4 are each provided with a second venting hole 6 corresponding to the first venting hole 34. When the antenna transmits electromagnetic waves, the electromagnetic waves are coupled to the signal connection terminal 33 of the radiating cavity unit 31 through the waveguide radiation gap 24. Then, the electromagnetic waves flow upwards from the signal connection terminal 33, radiating outwards through the radiation gap 32 on the radiating cavity unit 31, and simultaneously discharging excess or redundant electromagnetic wave energy through the first venting hole 34 to the multiple second venting holes 6, finally being received by the corresponding external receiving device.

[0043] Preferably, the waveguide radiation slot 24 and the radiation slot 32 have the same shape.

[0044] As shown in Figure 8, a specific embodiment of the present invention also provides a waveguide slot antenna control method, applied to the waveguide slot antenna as described above. The steps of the method include:

[0045] S101. Obtain electromagnetic wave signals and control instructions at a preset frequency;

[0046] It should be noted that, in order to meet the electromagnetic wave operation requirements of different transmission frequencies, the waveguide slot antenna is controlled to radiate electromagnetic waves at the corresponding frequencies by acquiring the electromagnetic wave signal and control operation commands of that frequency.

[0047] S102. When the control operation command is a preset operation command, the electromagnetic wave signal is transmitted to the feed port in the feed port layer, and transmitted through the feed port to the feed signal terminal on the slow wave line layer.

[0048] It should be noted that the preset working command is the transmission command. When the control working command is the transmission command, the electromagnetic wave signal of that frequency is transmitted to the feed port in the feed port layer, and then transmitted to the feed signal end on the slow wave line layer through the feed port, so as to realize the electromagnetic wave signal coupling transmission.

[0049] S103. The electromagnetic wave signal is transmitted along the serpentine channel of the serpentine slow wave cavity through the feed signal terminal. When the electromagnetic wave signal passes through the waveguide radiation slots in the serpentine channel in sequence, the electromagnetic wave signal will be coupled to the signal connection terminal in the corresponding radiation cavity unit by the waveguide radiation slots in sequence.

[0050] S104. The electromagnetic wave signal is transmitted along the channel of the radiation cavity unit through the signal connection terminal. When the electromagnetic wave signal passes through the radiation slit in sequence, the radiation slit radiates the electromagnetic wave signal outward.

[0051] It should be noted that when the electromagnetic wave signal passes through the waveguide radiation slots in the serpentine channel in sequence, the electromagnetic wave signal is coupled by the waveguide radiation slots to the signal connection terminal in the corresponding radiation cavity unit, and then transmitted to the other end of the radiation cavity unit through the signal connection terminal. During this process, as the electromagnetic wave signal passes through the radiation slots in sequence, the radiation slots radiate the electromagnetic wave signal outward, realizing the transmission of electromagnetic waves at the corresponding frequency. In the above-described transmission or transmission scanning mode, this invention, by changing the transmission frequency of the electromagnetic wave, causes a greater shift in the direction of the main beam of the antenna array pattern within the limited operating frequency band of the antenna array, thereby improving the scanning angle and meeting the requirements of applications with high antenna scanning angle requirements. The scanning angle in the 79GHz-81GHz frequency band can reach 16°.

[0052] In summary, the present invention has a simple structure, consisting of multiple stacked layered plates, which facilitates production, processing, and installation. The constructed slow-wave line structure can improve antenna gain, thereby increasing the antenna scanning angle within a limited operating frequency band, making it suitable for applications with high antenna scanning angle requirements and highly adaptable.

[0053] Furthermore, the specific structure of the slow-wavelength layer of the present invention will be further described below:

[0054] As shown in Figure 9, the centerline of the straight waveguide segment 231 in the slow wave line layer 2 is offset from the centerline of the corresponding waveguide radiation slot 24 to achieve the offset of the centerline of the waveguide radiation slot 24. By adjusting the offset of the waveguide radiation slot 24, its equivalent conductivity can be increased, thereby increasing the electromagnetic wave energy radiated or coupled to the lower unit, that is, increasing the radiated power, and thus improving the antenna radiation or scanning effect.

[0055] The centerlines of the multiple waveguide radiation slots 24 have different offsets (d) to achieve different required radiation power. By setting the offset of the centerlines of the multiple waveguide radiation slots 24, the slow wave line layer 2 exhibits a radiation effect that is strong in the middle and weak on both sides, thereby improving the antenna scanning effect. When the electromagnetic wave signal radiates outward, it propagates along the serpentine channel 23. Each time the electromagnetic wave signal flows through a waveguide radiation slot 24, part of its electromagnetic wave energy is radiated outward through that slot, while the remaining electromagnetic wave energy continues to flow backward, gradually weakening. By adjusting the offset of the waveguide radiation slots 24 along the direction of the serpentine channel 23, the antenna radiation effect exhibits a radiation waveform that is strong in the middle and weak on both sides, thereby improving the antenna radiation intensity and radiation distance, meeting the user's long-distance antenna scanning requirements.

[0056] Furthermore, the cross-section of the straight waveguide segment 231 includes a wide side dimension a and a narrow side dimension b. The wide side dimension a is the width dimension of the straight waveguide segment 231, and the narrow side dimension b is the depth dimension of the straight waveguide segment 231. The ratio c = b / a of the narrow side dimension b to the wide side dimension a is 0.2 ≤ c ≤ 0.9.

[0057] For example, the ratio c of the narrow side dimension b of the waveguide to the wide side dimension a of the waveguide is 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8 and 0.9, but is not limited to these. When the ratio c is too large, it is easy to cause the waveguide structure and the overall antenna to be large in size and occupy a lot of space, increasing the structural cost; at the same time, the larger the cross-sectional area of ​​the waveguide, the lower the cutoff frequency will be, affecting the application range of the antenna's operating frequency band.

[0058] Furthermore, the ratio e = d / a of the offset d of the centerline of the waveguide radiation slot 24 relative to the centerline of the straight waveguide segment 231 to the width dimension a of the waveguide is 0 < e < 0.5, and the equivalent conductivity of the waveguide radiation slot 24 increases as the ratio e increases.

[0059] For example, the ratio e of the offset of the centerline of the waveguide radiation slot 24 relative to the centerline of the straight waveguide segment 231 to the width dimension of the waveguide is 0.05, 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40, 0.45 and 0.49, but is not limited to this. When the ratio e is too large, it is easy to affect the equivalent conductivity of the waveguide radiation slot 24, reduce the radiation energy of electromagnetic waves, and thus affect the antenna radiation or scanning effect.

[0060] Wherein, the wide side dimension a of the waveguide is 1.37mm≤a≤4mm, the narrow side dimension b of the waveguide is 0.5mm≤b≤3.6mm, and the offset d of the center line of the waveguide radiation slot 24 relative to the center line of the straight waveguide segment 231 is 0.005mm≤d≤1.8mm. Within this range, the serpentine slow wave slot 22 has a smaller overall volume and can take into account both higher intensity radiation energy and a longer scanning distance, resulting in the best overall performance.

[0061] For example, the waveguide wide side dimension a is 1.37mm, 1.50mm, 1.75mm, 2.00mm, 2.25mm, 2.3mm, 2.5mm, 2.75mm, 3.0mm, 3.25mm, 3.75mm or 4.0mm, but is not limited thereto.

[0062] For example, the narrow side dimension b of the waveguide is 0.5mm, 1.00mm, 1.50mm, 2.00mm, 2.5mm, 23.0mm, 3.5mm or 3.6mm, but is not limited thereto.

[0063] For example, the offset d of the centerline of the waveguide radiation slot 24 relative to the centerline of the straight waveguide segment 231 is 0.005mm, 0.008mm, 0.0010mm, 0.015mm, 0.020mm, 0.025mm, 0.030mm, 0.035mm, 0.040mm, 0.045mm, 0.050mm, 0.055mm, 0.060mm, 0.065mm, 0.070mm, 0.075mm, 0.080mm, 0.085mm, 0.090mm, 0.095mm, 0.010mm, 0.050mm, 0.100mm, 0.150mm, 0.200mm, 0 0.250mm, 0.300mm, 0.350mm, 0.400mm, 0.450mm, 0.500mm, 0.550mm, 0.600mm, 0.650mm, 0.700mm, 0.850mm, 0.900mm, 0.950mm, 1.000mm, 1.050mm, 1.100mm, 1.150mm, 1.200mm, 1.250mm, 1.300mm, 1.350mm, 1.400mm, 1.450mm, 1.500mm, 1.550mm, 1.600mm, 1.650mm, 1.700mm, 1.750mm, or 1.800mm, but not limited to these.

[0064] It should be noted that the wavelength range of the electromagnetic wave can be obtained based on the operating frequency range of the antenna application. For example, the operating frequency range of the W-band is 75~110GHz, corresponding to a wavelength range of approximately 2.73~4mm, and a half-wavelength range of 1.36~2mm. That is, given a specific operating frequency, the wavelength of the corresponding electromagnetic wave can be obtained. The waveguide width dimension 'a' is chosen to be greater than half the wavelength (i.e., half-wavelength): a>λ / 2. The waveguide wavelength λ of this waveguide element can be determined using the waveguide width dimension 'a' and the electromagnetic wave wavelength λ. g As shown in Figure 10, when the waveguide wide side dimension a, the waveguide narrow side dimension b, the electromagnetic wave wavelength λ, and the waveguide wavelength λ... g When the value of is determined, the larger the ratio of the offset of the center line of the waveguide radiation slot 24 to the width of the waveguide, that is, the larger the offset d of the center line of the waveguide radiation slot 24 relative to the center line of the straight waveguide segment 231, the larger the equivalent conductivity of the waveguide radiation slot 24, the greater the radiation energy and radiation power, and the farther the radiation or scanning distance.

[0065] Preferably, the waveguide radiation slot 24 is strip-shaped, and the two ends of the waveguide radiation slot 24 are semi-circular.

[0066] In some embodiments, the length of the straight waveguide segment 231 in the slow waveline layer 2 is 2~25mm, the width of the straight waveguide segment 231 is 1.37~4mm, the depth of the straight waveguide segment 231 is 0.5~3.6mm, the length of the connecting waveguide segment 232 is 1.6~25mm, and the width of the gap is 0.25~1mm; the length of the waveguide radiation slot 24 is 1.37~2.5mm, the width of the waveguide radiation slot 24 is 0.1~0.8mm, the offset d of the centerline of the waveguide radiation slot 24 relative to the centerline of the straight waveguide segment 231 is 0.005~1.8mm, the length of the slow waveline layer 2 is 50~400mm, and the width of the slow waveline layer 2 is 5~150mm. Slow-wave line layer and waveguide slot antennas within this range are better suited for use in the W-band (75~110GHz) operating range. They can radiate electromagnetic waves that are strong in the middle and weak on both sides, and have the characteristics of small overall size, wide radiation range, strong radiation energy and long radiation distance.

[0067] The slow-wavelength layer 2 of the present invention will be further described below with reference to the accompanying drawings and embodiments: Example

[0068] This invention provides a slow-waveline layer 2. One end of the slow-waveline layer 2 facing the feed port layer 1 has a serpentine slow-wave cavity 21. One end of the serpentine slow-wave cavity 21 has a feed signal terminal 22, which is connected to the feed port 11 to achieve electromagnetic wave transmission. Multiple waveguide radiation slots 24 are spaced apart in the serpentine channel 23 of the serpentine slow-wave cavity 21. The serpentine channel 23 includes several straight waveguide segments 231 and connecting waveguide segments 232. A gap is left between adjacent straight waveguide segments 231 to separate them and avoid signal interference. Adjacent straight waveguide segments 231 are connected by the connecting waveguide segments 232 to construct a slow-waveline structure. The centerlines of the straight waveguide segments 231 in the slow-waveline layer 2 are staggered from the centerlines of their corresponding waveguide radiation slots 24.

[0069] In this embodiment, the length of the straight waveguide segment 231 is preferably 9.4 mm, the width (i.e., the wide side dimension a) of the straight waveguide segment 231 is 2.3 mm, the depth (i.e., the narrow side dimension b) of the straight waveguide segment 231 is 1.61 mm, the length of the connecting waveguide segment 232 is 4.4 mm, and the width of the gap is 0.5 mm; the length of the waveguide radiation slot 24 is 1.9 mm, the width of the waveguide radiation slot 24 is 0.4 mm, the offset d of the centerline of the waveguide radiation slot 24 relative to the centerline of the straight waveguide segment 231 is 0.02-0.10 mm, the offset d of the centerlines of the multiple waveguide radiation slots 24 relative to the centerline of the straight waveguide segment 231 is different, and the offset first increases and then decreases along the transmission direction of the serpentine channel 23; the length of the slow waveline layer 2 is 184.8 mm, and the width of the slow waveline layer 2 is 15 mm.

[0070] In this embodiment, the ratio c of the narrow side dimension b of the waveguide to the wide side dimension a of the waveguide is 0.7, and the ratio e of the offset d of the center line of the waveguide radiation slot 24 relative to the center line of the straight waveguide segment 231 to the wide side dimension a of the waveguide is 0.008≤e≤0.043.

[0071] In this embodiment, the operating frequency is 79-80GHz. Example

[0072] This invention provides a slow-waveline layer 2. One end of the slow-waveline layer 2 facing the feed port layer 1 has a serpentine slow-wave cavity 21. One end of the serpentine slow-wave cavity 21 has a feed signal terminal 22, which is connected to the feed port 11 to achieve electromagnetic wave transmission. Multiple waveguide radiation slots 24 are spaced apart in the serpentine channel 23 of the serpentine slow-wave cavity 21. The serpentine channel 23 includes several straight waveguide segments 231 and connecting waveguide segments 232. A gap is left between adjacent straight waveguide segments 231 to separate them and avoid signal interference. Adjacent straight waveguide segments 231 are connected by the connecting waveguide segments 232 to construct a slow-waveline structure. The centerlines of the straight waveguide segments 231 in the slow-waveline layer 2 are staggered from the centerlines of their corresponding waveguide radiation slots 24.

[0073] The length of the straight waveguide segment 231 is preferably 3 mm, the width (i.e., the wide side dimension a) of the straight waveguide segment 231 is 2.3 mm, the depth (i.e., the narrow side dimension b) of the straight waveguide segment 231 is 1.61 mm, the length of the connecting waveguide segment 232 is 4.4 mm, and the width of the gap is 0.5 mm; the length of the waveguide radiation slot 24 is 1.9 mm, the width of the waveguide radiation slot 24 is 0.4 mm, the offset d of the centerline of the waveguide radiation slot 24 relative to the centerline of the straight waveguide segment 231 is 0.02-0.10 mm, the offset d of the centerlines of the multiple waveguide radiation slots 24 relative to the centerline of the straight waveguide segment 231 is different, and the offset first increases and then decreases along the transmission direction of the serpentine channel 23; the length of the slow waveline layer 2 is 184.8 mm, and the width of the slow waveline layer 2 is 15 mm. It should be noted that when the length of the straight waveguide segment 231 or the connecting waveguide segment 232 changes, it will affect the antenna beam scanning pointing angle to a certain extent and reduce the antenna scanning angle.

[0074] In this embodiment, the ratio c of the narrow side dimension b of the waveguide to the wide side dimension a of the waveguide is 0.7, and the ratio e of the offset d of the center line of the waveguide radiation slot 24 relative to the center line of the straight waveguide segment 231 to the wide side dimension a of the waveguide is 0.008≤e≤0.043.

[0075] In this embodiment, the operating frequency is 79-80GHz. Example

[0076] This invention provides a slow-waveline layer 2. One end of the slow-waveline layer 2 facing the feed port layer 1 has a serpentine slow-wave cavity 21. One end of the serpentine slow-wave cavity 21 has a feed signal terminal 22, which is connected to the feed port 11 to achieve electromagnetic wave transmission. Multiple waveguide radiation slots 24 are spaced apart in the serpentine channel 23 of the serpentine slow-wave cavity 21. The serpentine channel 23 includes several straight waveguide segments 231 and connecting waveguide segments 232. A gap is left between adjacent straight waveguide segments 231 to separate them and avoid signal interference. Adjacent straight waveguide segments 231 are connected by the connecting waveguide segments 232 to construct a slow-waveline structure. The centerlines of the straight waveguide segments 231 in the slow-waveline layer 2 are staggered from the centerlines of their corresponding waveguide radiation slots 24.

[0077] The length of the straight waveguide segment 231 is preferably 9.4 mm, the width (i.e., waveguide wide side dimension a) of the straight waveguide segment 231 is 2.3 mm, the depth (i.e., waveguide narrow side dimension b) of the straight waveguide segment 231 is 1.61 mm, the length of the connecting waveguide segment 232 is 4.4 mm, and the width of the gap is 0.5 mm; the length of the waveguide radiation slot 24 is 1.9 mm, the width of the waveguide radiation slot 24 is 0.4 mm, the offset d of the centerline of the waveguide radiation slot 24 relative to the centerline of the straight waveguide segment 231 is 0.07-0.13 mm, the offset d of the centerlines of the multiple waveguide radiation slots 24 relative to the centerline of the straight waveguide segment 231 is different, and the offset first increases and then decreases along the transmission direction of the serpentine channel 23; the length of the slow waveline layer 2 is 89.6 mm, and the width of the slow waveline layer 2 is 15 mm. It should be noted that when the length of the slow wave line layer 2 is reduced, in order to retain better performance effects such as antenna gain and sidelobe level, the offset of the center line of the waveguide radiation slot 24 relative to the center line of the straight waveguide segment 231 can be adjusted accordingly to adapt to the shorter serpentine slow wave plate.

[0078] In this embodiment, the ratio c of the narrow side dimension b of the waveguide to the wide side dimension a of the waveguide is 0.7, and the ratio e of the offset d of the center line of the waveguide radiation slot 24 relative to the center line of the straight waveguide segment 231 to the wide side dimension a of the waveguide is 0.030≤e≤0.056.

[0079] In this embodiment, the operating frequency is 79-80GHz. Example

[0080] This invention provides a slow-waveline layer 2. One end of the slow-waveline layer 2 facing the feed port layer 1 has a serpentine slow-wave cavity 21. One end of the serpentine slow-wave cavity 21 has a feed signal terminal 22, which is connected to the feed port 11 to achieve electromagnetic wave transmission. Multiple waveguide radiation slots 24 are spaced apart in the serpentine channel 23 of the serpentine slow-wave cavity 21. The serpentine channel 23 includes several straight waveguide segments 231 and connecting waveguide segments 232. A gap is left between adjacent straight waveguide segments 231 to separate them and avoid signal interference. Adjacent straight waveguide segments 231 are connected by the connecting waveguide segments 232 to construct a slow-waveline structure. The centerlines of the straight waveguide segments 231 in the slow-waveline layer 2 are staggered from the centerlines of their corresponding waveguide radiation slots 24.

[0081] The length of the straight waveguide segment 231 is preferably 8 mm, the width (i.e., the wide side dimension a) of the straight waveguide segment 231 is 1.96 mm, the depth (i.e., the narrow side dimension b) of the straight waveguide segment 231 is 1.37 mm, the length of the connecting waveguide segment 232 is 3.74 mm, and the width of the gap is 0.425 mm; the length of the waveguide radiation slot 24 is 1.62 mm, the width of the waveguide radiation slot 24 is 0.34 mm, the offset d of the centerline of the waveguide radiation slot 24 relative to the centerline of the straight waveguide segment 231 is 0.017-0.085 mm, the offset d of the centerlines of the multiple waveguide radiation slots 24 relative to the centerline of the straight waveguide segment 231 is different, and the offset first increases and then decreases along the transmission direction of the serpentine channel 23; the length of the slow waveline layer 2 is 157.7 mm, and the width of the slow waveline layer 2 is 12.75 mm.

[0082] In this embodiment, the ratio c of the narrow side dimension b of the waveguide to the wide side dimension a of the waveguide is 0.7, and the ratio e of the offset d of the center line of the waveguide radiation slot 24 relative to the center line of the straight waveguide segment 231 to the wide side dimension a of the waveguide is 0.008≤e≤0.043.

[0083] In this embodiment, the operating frequency is 92-93 GHz.

[0084] By proportionally adjusting the parameters of the slow-wave line layer 2, it is possible to adapt to scanning operations in different operating frequency bands and obtain better antenna radiation performance.

[0085] Comparative Example 1

[0086] This invention provides a slow-waveline layer 2. One end of the slow-waveline layer 2 facing the feed port layer 1 has a serpentine slow-wave cavity 21. One end of the serpentine slow-wave cavity 21 has a feed signal terminal 22, which is connected to the feed port 11 to achieve electromagnetic wave transmission. Multiple waveguide radiation slots 24 are spaced apart in the serpentine channel 23 of the serpentine slow-wave cavity 21. The serpentine channel 23 includes several straight waveguide segments 231 and connecting waveguide segments 232. A gap is left between adjacent straight waveguide segments 231 to separate them and avoid signal interference. Adjacent straight waveguide segments 231 are connected by the connecting waveguide segments 232 to construct a slow-waveline structure. The centerlines of the straight waveguide segments 231 in the slow-waveline layer 2 are staggered from the centerlines of their corresponding waveguide radiation slots 24.

[0087] In this embodiment, the length of the straight waveguide segment 231 is preferably 9.4 mm, the width of the straight waveguide segment 231 (i.e., the wide side dimension a) is 2.3 mm, the depth of the straight waveguide segment 231 (the narrow side dimension b) is 1.61 mm, the length of the connecting waveguide segment 232 is 4.4 mm, and the width of the gap is 0.5 mm; the length of the waveguide radiation slot 24 is 1.9 mm, the width of the waveguide radiation slot 24 is 0.4 mm, the offset d of the centerline of the waveguide radiation slot 24 relative to the centerline of the straight waveguide segment 231 is 0.05 mm, the length of the slow waveline layer 2 is 184.8 mm, and the width of the slow waveline layer 2 is 15 mm.

[0088] In this embodiment, the ratio c of the narrow side dimension b of the waveguide to the wide side dimension a of the waveguide is 0.7, and the ratio e of the offset d of the centerline of the waveguide radiation slot 24 relative to the centerline of the straight waveguide segment 231 to the wide side dimension a of the waveguide is 0.021.

[0089] In this embodiment, the operating frequency is 79-80GHz.

[0090] Comparative Example 2

[0091] This invention provides a slow-waveline layer 2. One end of the slow-waveline layer 2 facing the feed port layer 1 has a serpentine slow-wave cavity 21. One end of the serpentine slow-wave cavity 21 has a feed signal terminal 22, which is connected to the feed port 11 to achieve electromagnetic wave transmission. Multiple waveguide radiation slots 24 are spaced apart in the serpentine channel 23 of the serpentine slow-wave cavity 21. The serpentine channel 23 includes several straight waveguide segments 231 and connecting waveguide segments 232. A gap is left between adjacent straight waveguide segments 231 to separate them and avoid signal interference. Adjacent straight waveguide segments 231 are connected by the connecting waveguide segments 232 to construct a slow-waveline structure. The centerline of each straight waveguide segment 231 coincides with the centerline of its corresponding waveguide radiation slot 24.

[0092] In this embodiment, the length of the straight waveguide segment 231 is preferably 9.4 mm, the width of the straight waveguide segment 231 (i.e., the waveguide wide side dimension a) is 2.3 mm, the depth of the straight waveguide segment 231 (i.e., the waveguide narrow side dimension b) is 1.61 mm, the length of the connecting waveguide segment 232 is 4.4 mm, and the width of the gap is 0.5 mm; the length of the waveguide radiation slot 24 is 1.9 mm, the width of the waveguide radiation slot 24 is 0.4 mm, the offset d of the centerline of the waveguide radiation slot 24 relative to the centerline of the straight waveguide segment 231 is 0 mm, the length of the slow waveline layer 2 is 184.8 mm, and the width of the slow waveline layer 2 is 15 mm.

[0093] In this embodiment, the ratio c of the narrow side dimension b of the waveguide to the wide side dimension a of the waveguide is 0.7, and the ratio e of the offset d of the centerline of the waveguide radiation slot 24 relative to the centerline of the straight waveguide segment 231 to the wide side dimension a of the waveguide is 0.

[0094] In this embodiment, the operating frequency is 79-80GHz.

[0095] The performance of the serpentine slow-wave plates prepared in Examples 1 to 4 and Comparative Examples 1 to 2 was tested, and the normalized electromagnetic wave radiation patterns shown in Figures 11 to 16 were obtained. The test results are shown in Table 1 below:

[0096] Table 1 Test Results

[0097]

[0098] As can be seen from the above test results and the normalized radiation pattern of electromagnetic waves, compared with comparative examples 1 to 2, these embodiments 1 to 4 have lower sidelobe levels and higher antenna gain, and their radiation range and distance are relatively longer, resulting in better electromagnetic wave radiation or scanning effects.

[0099] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A waveguide slot antenna, characterized in that, It includes a feed port layer, a slow wave line layer, and a radiation slot layer stacked in sequence; The feed port layer is provided with feed ports for inputting electromagnetic waves or outputting electromagnetic waves. The slow wave line surface is provided with a serpentine slow wave cavity on one end face facing the feed port layer. One end of the serpentine slow wave cavity is provided with a feed signal terminal, which is connected to the feed port. Multiple waveguide radiation slots are provided at intervals in the serpentine channel of the serpentine slow wave cavity. Multiple radiating cavity units are spaced apart on one end face of the radiating slot layer facing the slow waveline layer. Each radiating cavity unit is arranged in a one-to-one correspondence with the waveguide radiating slot. Multiple radiating slots are spaced apart inside each radiating cavity unit. One end of each radiating cavity unit is provided with a signal connection terminal that is coupled to the waveguide radiating slot.

2. The waveguide slot antenna as described in claim 1, characterized in that, Each straight waveguide segment in the serpentine channel is provided with the waveguide radiation slot, and the serpentine channel is located below the feed signal end.

3. The waveguide slot antenna as described in claim 2, characterized in that, The centerline of the straight waveguide segment is offset from the centerline of its corresponding waveguide radiation slot, and the centerlines of the multiple waveguide radiation slots have different offsets.

4. The waveguide slot antenna as described in claim 3, characterized in that, The cross-section of the straight waveguide segment includes a wide side dimension a and a narrow side dimension b. The ratio e = d / a of the offset d of the centerline of the waveguide radiation slot relative to the centerline of the straight waveguide segment to the wide side dimension a is 0 < e < 0.

5. The equivalent conductivity of the waveguide radiation slot increases as the ratio e increases.

5. The waveguide slot antenna as described in claim 4, characterized in that, The wide side dimension a of the waveguide is 1.37mm≤a≤4mm, the narrow side dimension b of the waveguide is 0.5mm≤b≤3.6mm, and the offset d of the centerline of the waveguide radiation slot relative to the centerline of the straight waveguide segment is 0.005mm≤d≤1.8mm.

6. The waveguide slot antenna as described in claim 1, characterized in that, The radiation cavity unit has multiple radiation slots spaced upwards along the signal connection end, with adjacent radiation slots staggered on both sides of the vertical center line of the radiation cavity unit.

7. The waveguide slot antenna as described in any one of claims 1 to 6, characterized in that, A coupling layer is provided between the feed port layer and the slow wave line layer. The coupling layer has a coupling port corresponding to the feed port. The coupling port is connected to the feed port and the feed signal terminal respectively.

8. The waveguide slot antenna as described in claim 7, characterized in that, The other end of the serpentine slow wave cavity is provided with a signal discharge port, and both the power supply port layer and the coupling layer are provided with discharge ports corresponding to the signal discharge port.

9. The waveguide slot antenna as described in claim 8, characterized in that, The radiation cavity unit is provided with a first vent hole at the end away from the signal connection terminal, and the feed port layer, the slow wave line layer and the coupling layer are each provided with a second vent hole corresponding to the first vent hole.

10. A waveguide slot antenna control method, characterized in that: Applied to a waveguide slot antenna as described in any one of claims 1 to 9, the method comprises the following steps: Acquire electromagnetic wave signals of a preset frequency and control commands; When the control command is a preset command, the electromagnetic wave signal is transmitted to the feed port in the feed port layer, and then transmitted to the feed signal terminal on the slow wave line layer through the feed port. The electromagnetic wave signal is transmitted along the serpentine channel of the serpentine slow wave cavity through the feed signal terminal. When the electromagnetic wave signal passes through the waveguide radiation slots in the serpentine channel in sequence, the electromagnetic wave signal will be coupled to the signal connection terminal in the corresponding radiation cavity unit by the waveguide radiation slots in sequence. The electromagnetic wave signal is transmitted along the channel of the radiation cavity unit through the signal connection terminal. When the electromagnetic wave signal passes through the radiation slits in sequence, the radiation slits radiate the electromagnetic wave signal outward.

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