A Ku-band miniaturized multi-beam satellite antenna system

Abstract

The present invention relates to a Ku-band miniaturized multi-beam satellite antenna feed and antenna system, which comprises a feed module consisting of a first feed pointing to 90° and a plurality of second feeds arranged laterally, wherein the second feeds are distributed in a ring shape with the first feed as the center; a comprehensive processing unit connected to the feed module through a radio frequency switch, wherein the comprehensive processing unit consists of a down-conversion amplification module, a feed box and a control source; the control source controls the radio frequency switch to periodically switch the first feed and the second feed to be connected to the comprehensive processing unit. The present invention integrates eight directional antennas in a compact structure space through optimized design, and realizes time-sharing hemispherical space coverage through switching of the radio frequency switch. On the one hand, the antenna gain is improved; on the other hand, the narrow beam limits interference signals of other spatial angles from entering the receiving terminal, which effectively improves the terminal signal quality.

Description

Technical Field

[0001] The present invention relates to the field of antennas, and in particular to a Ku-band miniaturized multi-beam satellite antenna feed and an antenna system. Background Art

[0002] The frequency of the Ku-band is protected by relevant international laws and is in the 12-18GHz frequency band. The power of a single Ku-band satellite transponder is generally relatively large, and shaped beam coverage is mostly used. The satellite EIRP is relatively large, and the efficiency of the Ku-band receiving antenna is higher than that of the C-band receiving antenna. Therefore, the antenna aperture for receiving Ku-band satellite programs is much smaller than that of the C-band, which can effectively reduce the reception cost and facilitate individual reception. At present, the ground terminal of the Ku-band broadcast satellite system generally uses omnidirectional antennas to receive signals indiscriminately in a hemispherical space. The omnidirectional antenna radiation pattern covers a hemispherical space and has a low gain. At the same time, due to the large number of commercial satellites in the Ku-band, the omnidirectional antenna receives more interference signals from various angles, which can easily cause the loss of received data and lead to system failure. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a Ku-band miniaturized multi-beam satellite antenna feed and antenna system, which integrates eight directional antennas in a compact structure space and realizes time-sharing hemispherical space coverage through RF switch switching. On the one hand, the antenna gain is improved; on the other hand, the narrow beam limits the interference signals from other spatial angles from entering the receiving terminal, effectively improving the terminal signal quality.

[0004] The objective of the present invention is achieved through the following technical solutions:

[0005] A Ku-band miniaturized multi-beam satellite antenna feed comprises a first feed pointing at 90 degrees and a plurality of second feeds arranged laterally, wherein the second feeds are distributed in a ring shape with the first feed as the center.

[0006] Furthermore, the lateral deflection angle of the second feed source is 54° deflected from the first feed source pointing at 90°.

[0007] Furthermore, there are seven second feed sources, and the seven second feed sources are evenly distributed in a ring shape with the first feed source as the center.

[0008] Furthermore, the first feed source and the second feed source adopt a dual-feed-point double-layer microstrip patch antenna, wherein the first layer is a radiation unit, and the second layer is a microstrip power divider that provides a dual excitation source for the upper radiation unit.

[0009] Furthermore, the four corners of the first feed source and the second feed source are fixed to the feed source base by M2 screws.

[0010] A Ku-band miniaturized multi-beam satellite antenna system, characterized in that the system comprises:

[0011] A feed module consisting of a first feed pointing at 90° and a plurality of second feeds arranged laterally, wherein the second feeds are distributed in a ring around the first feed;

[0012] An integrated processing unit connected to the feed source module via a radio frequency switch, the integrated processing unit consisting of a down-conversion amplifier module, a feed box and a control source;

[0013] The control source controls the radio frequency switch to periodically switch the first feed source and the second feed source to be connected to the integrated processing unit.

[0014] Furthermore, the feed module, the radio frequency switch and the integrated processing unit are fixed on a base via a mounting frame.

[0015] Furthermore, an antenna cover is provided outside the feed module, the radio frequency switch and the integrated processing unit, and the antenna cover is fixedly connected to the base by bolts.

[0016] Furthermore, the radio frequency switch is a single-pole multi-throw switch, which is used to connect the first feed source or any second feed source with the integrated processing unit.

[0017] Furthermore, the output signal of the integrated processing unit is connected to a receiving terminal.

[0018] The beneficial effects of the present invention are as follows: the present invention integrates eight directional antennas in a compact structure space through optimized design, and realizes time-sharing hemispherical space coverage through RF switch switching. On the one hand, the antenna gain is improved; on the other hand, the narrow beam limits the interference signals from other spatial angles from entering the receiving terminal, effectively improving the terminal signal quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic diagram of the antenna system of the present invention;

[0020] Figure 2 is an exploded diagram of the antenna system of the present invention;

[0021] Figure 3 It is a schematic diagram of the antenna system assembly of the present invention;

[0022] Figure 4 yes Figure 3 A top view of

[0023] Figure 5 is a schematic diagram of the feed module;

[0024] Figure 6 is a schematic diagram of the angle distribution of the second feed;

[0025] Figure 7 is a schematic diagram of the structure of the integrated processing unit;

[0026] Figure 8 It is a schematic diagram of the RF switch structure. DETAILED DESCRIPTION

[0027] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings, but the protection scope of the present invention is not limited to the following.

[0028] The present invention provides a Ku-band miniaturized multi-beam satellite antenna system, the system composition of which can refer to Figure 1 As shown, it is mainly composed of a radome 1, a feed module 2, a radio frequency switch 3 and an integrated processing unit 5. In order to achieve the purpose of the present invention, this embodiment also provides a Ku-band miniaturized multi-beam satellite antenna feed, wherein the Ku-band miniaturized multi-beam satellite antenna system is implemented based on the Ku-band miniaturized multi-beam satellite antenna feed.

[0029] refer to Figure 5 As shown, a Ku-band miniaturized multi-beam satellite antenna feed includes a first feed 23 pointing at 90° and a plurality of second feeds 22 arranged laterally, wherein the second feeds 22 are distributed in a ring around the first feed 23. The lateral deflection angle of the second feed 22 is 54° from the 90° direction. The structural distribution thereof can be referred to Figure 6 More specifically, there are seven second feed sources 22, and the seven second feed sources 22 are evenly distributed in a ring shape with the first feed source 23 as the center.

[0030] That is to say, a total of eight feeds are integrated in this solution, and the feed mounting frame of the overall structure ensures the relative position accuracy of the eight feeds, one of which (the first feed 23) points to 90°, and the remaining seven feeds (the second feed 22) are evenly distributed along the circumference with a vertical deflection of 54°.

[0031] After design, the optimal 8-beam solution is adopted, with one on the top and the lateral beam deviating from the axial beam by 54 degrees. When 7 beams are arranged at an interval of 51.43 degrees, the design requirements are fully met.

[0032] Noise Figure Noise temperature Gain G / T value 1.5 119.6358879 0.8 -19.97861477

[0033] Normally, the Ku-band LNB noise figure is 1.5dB, which requires the net gain of the antenna within the coverage area to be greater than or equal to 0.8dBi. After preliminary evaluation by various professionals, the Ku-band radome loss is 0.5dB, and the insertion loss of the Ku-band single-pole eight-throw RF switch is less than 2.5dB, so the gain within the 60° beam is required to be greater than 0.5+0.8+2.5=3.8dBi.

[0034] On the one hand, the first feed 23 and the second feed 22 use a dual-feed point double-layer microstrip patch antenna, wherein the first layer is a radiating unit and the second layer is a microstrip power divider that provides a dual excitation source for the upper radiating unit. The four corners of the first feed 23 and the second feed 22 are fixed to the feed base 21 by M2 screws. This design is to ensure miniaturization and good axial ratio indicators, and the model size of a single feed is 25mm×25mm×6mm.

[0035] According to the simulation results, at 12.25GHz and 12.75GHz, the feed normal gain is greater than 8dBi; at the 60° beam edge, the gain is as low as 5.3dBi, which is better than the design requirement of 3.8dBi; within the 60° beam coverage, the axial ratio is as high as 2.48dB, which is better than the design requirement of 3dB. All indicators meet the design requirements. The 8 feeds are integrated together, and the normal gain of each feed and the 60° beam edge gain are all better than the design value.

[0036] After completing the antenna feed design, this embodiment also provides a Ku-band miniaturized multi-beam satellite antenna system. Figure 1 As shown, the system includes:

[0037] A feed module 2 consisting of a first feed source 23 pointing at 90 degrees and a plurality of second feed sources 22 arranged laterally, wherein the second feed sources 22 are distributed in a ring around the first feed source 23;

[0038] The integrated processing unit 5 is connected to the feed source module 2 through an RF switch 3, and the integrated processing unit is composed of a down-conversion amplifier module, a feed box and a control source; the control source controls the RF switch 3 to periodically switch the first feed source 23 and the second feed source 22 to be connected to the integrated processing unit 5. The output signal of the integrated processing unit 5 is connected to the receiving terminal, and its hardware structure can be referred to Figure 7 shown.

[0039] The Ku-band miniaturized multi-beam antenna is mainly composed of a radome 1, a feed module 2, a radio frequency switch 3 and an integrated processing unit 5. Among them, the integrated processing unit 5 is composed of an LNB (down-conversion amplifier module), a feed box and a control source. When working, the control source sends instructions to make the radio frequency switch 3 switch periodically to achieve the purpose of switching the beam direction; when a certain feed source points to cover the satellite beam, the satellite radio frequency signal is received, and enters the LNB through the SP8T (single-pole eight-throw) radio frequency switch 3 for signal amplification, down-conversion, and output to the receiving terminal through the feed box.

[0040] The RF switch 3 is purchased as a mature product on the market. The design of this antenna requires the RF switch to have low insertion loss, compact structure, good adaptability, switching speed of seconds (time sensitivity requirement is not high), and low cost.

[0041] The indicators and structural dimensions of the RF switch 3 are as follows:

[0042] Working frequency: 12.25~12.75GHz;

[0043] Switch response time: ≤1us;

[0044] Insertion loss: ≤2.5dB;

[0045] On-off isolation of single-channel switch: ≥30dB;

[0046] Component input port standing wave: ≤1.5;

[0047] Component output port standing wave: ≤1.5;

[0048] Working voltage and current: +5V / 300mA;

[0049] Working voltage and current: -5V / -40mA;

[0050] RF input: SSMA-K;

[0051] RF output: SSMA-K;

[0052] Power supply and control interface: J30J-9ZKP;

[0053] Pinout 1 2 3 4 5 6 7 8 9 definition +5V power input GND(+5V) -5V power input GND(-5V) RXD+ RXD- TXD+ TXD- GND

[0054] The integrated processing unit 5 consists of LNB (down-conversion amplifier channel), feed box and RS422 control source. Functionally, it amplifies and down-converts the RF signal; distributes the input power supply and coherent signal, and combines the input and output signals; provides control indicators for the RF switch, performs periodic switching, and the switching period is adjustable.

[0055] Due to the requirement of miniaturization design, in order to reduce the interfaces between internal modules, and the LNB itself needs to be designed with a feed box function, the three modules are physically combined together and are collectively called an integrated processing unit.

[0056] Since there are abundant mature Ku-band LNB products on the market, we can directly make customized purchases.

[0057] The indicators and structural dimensions of the comprehensive processing unit 5 are as follows:

[0058] Input frequency: 12.25~12.75GHz;

[0059] Output intermediate frequency: 2.5~3 GHz;

[0060] Noise coefficient: ≤1dB;

[0061] Gain: ≥55dB;

[0062] VSWR: ≤2dB;

[0063] The 8 channels of the RF switch are switched periodically, and the switching period is configurable.

[0064] Size: 85mmx40mmx35mm;

[0065] RF input interface: SSMA-K;

[0066] Control signal output interface: J30J-9ZKP;

[0067] IF output, feed / coherent input interface: SSMA;

[0068] Feed voltage: 9~18V;

[0069] External reference: ﹣3~﹢3dBm@10MHz;

[0070] Power supply and control interface: J30J-9ZKP;

[0071] Interface definition: Same as SP8T RF switch.

[0072] refer to Figure 2 , Figure 3 as well as Figure 4 As shown, the feed module 2, the RF switch 3 and the integrated processing unit 5 are fixed on a base 4 through a mounting frame 6. The feed module 2, the RF switch 3 and the integrated processing unit 5 are provided with an antenna cover 1 outside, and the antenna cover 1 is fixedly connected to the base 4 by bolts. The RF switch 3 is a single-pole multi-throw switch, which is used to connect the first feed source 23 or any second feed source 22 with the integrated processing unit 5. In this embodiment, the RF switch 3 is a single-pole eight-throw switch, and its specific structure can be referred to Figure 8 shown.

[0073] On the other hand, the interior of the antenna is divided according to functions and modular design measures are adopted, fully considering interchangeability and maintainability; sealing strips and waterproof structures are designed, and waterproof sockets are selected, which are combined with the antenna cover 1 to form an overall sealing structure to prevent rain and humid air from entering the antenna and affecting the antenna performance, thereby improving the reliability of the antenna.

[0074] The antenna has two working modes, automatic mode and test mode. In automatic mode, the device automatically switches according to the pre-set switching cycle (initial value is 20s); in test mode, you need to connect the test interface and use a computer to set the cycle time or fixed direction control.

[0075] The above is only a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art shall not deviate from the spirit and scope of the present invention, and shall be within the scope of protection of the claims attached to the present invention.

Claims

1. A Ku-band miniaturized multi-beam satellite antenna system, characterized in that: The system comprises: a feed module (2) composed of a first feed source (23) pointing at 90 degrees and a plurality of second feed sources (22) arranged laterally, wherein the second feed sources (22) are distributed in a ring shape with the first feed source (23) as the center; a comprehensive processing unit (5) connected to the feed module (2) via a radio frequency switch (3), wherein the comprehensive processing unit is composed of a down-conversion amplifier module, a feed box and a control source; the control source controls the radio frequency switch (3) to periodically switch the first feed source (23) and the second feed source (22) to be connected to the comprehensive processing unit (5); the first feed source (23) and the second feed source (22) adopt a double-feed point double-layer microstrip patch antenna, wherein the first layer is a radiation unit and the second layer is a microstrip power divider that provides a double excitation source for the upper radiation unit.

2. The Ku-band miniaturized multi-beam satellite antenna system according to claim 1, characterized in that: The feed source module (2), the radio frequency switch (3) and the integrated processing unit (5) are fixed on a base (4) via a mounting frame (6).

3. The Ku-band miniaturized multi-beam satellite antenna system according to claim 2, characterized in that: An antenna cover (1) is arranged outside the feed module (2), the radio frequency switch (3) and the integrated processing unit (5), and the antenna cover (1) is fixedly connected to the base (4) by bolts.

4. The Ku-band miniaturized multi-beam satellite antenna system according to claim 3, characterized in that: The radio frequency switch (3) is a single-pole multi-throw switch, which is used to connect the first feed source (23) or any second feed source (22) with the integrated processing unit (5).

5. The Ku-band miniaturized multi-beam satellite antenna system according to claim 4, characterized in that: The output signal of the integrated processing unit (5) is connected to the receiving terminal.

Images