Circuitry, receivers, antenna equipment, and aircraft used for RTK antennas

Abstract

This application discloses a circuit arrangement, an RTK receiver, an RTK antenna device, and an aircraft for an RTK antenna. The circuit arrangement is used to connect to the RTK antenna and at least constitutes part of the antenna receiving circuit. The circuit arrangement includes a filter circuit capable of conducting DC and attenuating signals in a first frequency band. The operating frequency bands of the RTK antenna include a second frequency band and a third frequency band, and the first frequency band is adjacent to or partially overlaps with the second and third frequency bands. This invention can suppress interference with signals in a predetermined frequency band, improving the reliability of RTK operation.

Description

Technical Field

[0001] This invention relates to RTK positioning technology, and more particularly, to circuitry for an RTK antenna, an RTK receiver, an RTK antenna device, and an aircraft equipped with an RTK antenna. Background Technology

[0002] In recent years, RTK (Real-time kinematic) positioning technology has been widely adopted for aircraft such as drones. RTK antennas typically operate on two frequency bands centered at approximately 1.2 GHz and 1.5 GHz. More precisely, the operating frequency range of RTK antennas is mainly distributed between 1176.45 MHz and 1278.75 MHz (including at least one of the L1 band of GPS positioning system, the B1 band of BeiDou positioning system, the E1 band of Galileo positioning system, and the G1 band of GLONASS positioning system), and between 1559 MHz and 1610 MHz (including at least one of the L2 and L5 bands of GPS positioning system, the B2 and B3 bands of BeiDou positioning system, and the G2 and G3 bands of GLONASS positioning system). On the other hand, most drones and other aircraft are also equipped with data link transmission modules for transmitting video, images, or other data. The legal frequency band for drone image data transmission is generally around 1.4 GHz. Summary of the Invention

[0003] The purpose of this invention is to provide a circuit device, receiver, antenna device, and aircraft for RTK antennas, for reducing interference in RTK reception, especially interference from the data link transmission module, thereby making the RTK antenna work more stably when the data link transmission module and the RTK antenna coexist.

[0004] According to one aspect of the present invention, a circuit arrangement for an RTK antenna is provided, the circuit arrangement being connected to the RTK antenna and at least forming part of an antenna receiving circuit, wherein the circuit arrangement includes a filter circuit capable of conducting DC and attenuating signals in a first frequency band that is adjacent to or partially overlaps with the operating frequency band of the RTK antenna.

[0005] Preferably, the first frequency band covers at least one of the frequency ranges of 1430-1438MHz and 1438-1444MHz. In an advantageous embodiment, the first frequency band may cover the frequency range of 1300-1500MHz.

[0006] In some embodiments, the filtering circuit may include a first power divider, a second power divider, a first bandpass filter and a second bandpass filter connected in parallel between the first power divider and the second power divider, and a DC-blocking inductor connected in parallel with at least the first bandpass filter and the second bandpass filter, wherein the first bandpass filter is used to pass signals in a second frequency band, the second bandpass filter is used to pass signals in a third frequency band, and the first frequency band is located between the second frequency band and the third frequency band.

[0007] More preferably, the minimum frequency value of the second frequency band is greater than or equal to the maximum frequency value of the first frequency band, while the maximum frequency value of the third frequency band is less than or equal to the minimum frequency value of the first frequency band.

[0008] Preferably, the first power divider and the second power divider are Wilkinson power dividers, and the first bandpass filter and the second bandpass filter are surface acoustic wave filters.

[0009] Preferably, the filtering circuit may further include: a first limiter connected in series with the first bandpass filter between the first power divider and the second power divider; and a second limiter connected in series with the second bandpass filter between the first power divider and the second power divider.

[0010] Preferably, the first limiter and the second limiter are located on the side closer to the RTK antenna, respectively, relative to the first bandpass filter and the second bandpass filter.

[0011] In some embodiments, the filtering circuit may include a first LC circuit and a second LC circuit, wherein the first LC circuit includes a first inductor and a first capacitor connected in parallel for series connection with the RTK antenna; and the second LC circuit includes a second inductor and a second capacitor connected in series for parallel connection with the RTK antenna via grounding.

[0012] Preferably, the circuit device may further include a short-circuit protection resistor connected in series with the filter circuit to prevent instantaneous interruption false alarms. The short-circuit protection resistor has a certain resistance value to suppress the instantaneous current in the circuit to a level below the current threshold that can trigger short-circuit protection.

[0013] The resistance value of the short-circuit protection resistor against false transient interruptions can be 18 to 82 ohms. For example, the resistance value of the short-circuit protection resistor against false transient interruptions is 20 to 24 ohms.

[0014] Preferably, the circuit arrangement may further include: a first SMA connector for connection to the RTK antenna; and a second SMA connector for connection to an RTK receiver for the RTK antenna, wherein the filtering circuit and the anti-false alarm short-circuit resistor are connected in series between the first SMA connector and the second SMA connector.

[0015] According to another aspect of the invention, an RTK receiver is provided, which includes the circuitry described above.

[0016] According to another aspect of the present invention, an RTK antenna device is provided, comprising an RTK antenna and circuitry as described above connected to the RTK antenna.

[0017] According to another aspect of the invention, an aircraft is provided, comprising: an RTK antenna; and a data link transmission module for transmitting images or data in a data link transmission band, the data link band being adjacent to or partially overlapping with the operating band of the RTK antenna, wherein the aircraft further comprises circuitry as described above, and the first band of the filtering circuitry of the circuitry covers the data link band.

[0018] The aircraft may also include an RTK receiver, and the circuitry may be connected between the RTK antenna and the RTK receiver, or integrated into the RTK antenna, or integrated into the RTK receiver.

[0019] According to embodiments of the present invention, the circuit device, receiver, antenna equipment, and aircraft for RTK antennas reduce the risk of RTK malfunction by providing a filtering circuit that attenuates signals in a predetermined frequency band on the receiving side of the RTK antenna, thereby reducing interference in RTK reception. Attached Figure Description

[0020] Other features, objects, and advantages of the invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0021] Figure 1 This is a schematic block diagram of an aircraft according to an embodiment of the present invention;

[0022] Figure 2 This is a schematic circuit diagram of a circuit device for an RTK antenna according to Embodiment 1 of the present invention;

[0023] Figure 3 This is a schematic diagram illustrating the relationship between the first frequency band, the second frequency band, and the third frequency band of the filter circuit in the circuit device for an RTK antenna according to Embodiment 2 of the present invention;

[0024] Figure 4 An example of a circuit arrangement for an RTK antenna according to Embodiment 2 of the present invention is schematically shown; and

[0025] Figure 5 Another example of a circuit arrangement for an RTK antenna according to Embodiment 2 of the present invention is shown schematically. Detailed Implementation

[0026] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0027] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0028] The inventors of this invention discovered that on aircraft such as drones, the data link transmission module and the RTK antenna are typically positioned at a relatively close distance. The RTK antenna generally operates in two frequency bands centered at approximately 1.2 GHz and 1.5 GHz. Specifically, the operating frequency range of the RTK antenna is mainly distributed between 1176.45 MHz and 1278.75 MHz (including at least one of the following: L1 band of GPS positioning system, B1 band of BeiDou positioning system, E1 band of Galileo positioning system, and G1 band of GLONASS positioning system). The frequency bands used for image transmission are typically 1559–1610 MHz (including at least one of the L2 and L5 bands of GPS positioning system, the B2 and B3 bands of BeiDou positioning system, and the G2 and G3 bands of GLONASS positioning system). However, the legal frequency bands used by data link transmission modules for image transmission are generally around 1.4 GHz, and in some cases, may extend down to 1.3 GHz. This means that signals used for image data transmission may fall into the operating frequency band of the RTK antenna, thus coupling into the RTK path and causing strong interference to RTK signal reception. In particular, the signals used for image transmission require significant power, and to increase the image transmission distance, the transmission power needs to be further increased. Therefore, signals used for image data transmission may even saturate the RTK receiver, causing receiver blockage and severely affecting positioning and navigation. This is especially dangerous for fixed-wing aircraft. To date, such risks have not been recognized or countermeasures have been developed.

[0029] In view of the above, the inventors of the present invention have proposed a circuit device for an RTK antenna and an aircraft incorporating the circuit device.

[0030] Figure 1 This is a schematic block diagram of an aircraft 1 according to an embodiment of the present invention. Figure 1 As shown, the aircraft 1 (e.g., a drone) includes an RTK antenna 11 for flight positioning and a data link transmission module 20 for transmitting images or data. The data link transmission module 20 transmits images or data in a data link transmission band that is adjacent to or partially overlaps with the operating band of the RTK antenna 11.

[0031] According to an embodiment of the present invention, the aircraft 1 further includes a circuit device 12 for the RTK antenna 11, which is connected to the RTK antenna 11 and at least constitutes part of the receiving circuit of the RTK antenna 11. The circuit device 12 includes a filtering circuit capable of attenuating signals in a first frequency band that is adjacent to or partially overlaps with the operating frequency band of the RTK antenna 11. Specifically, the first frequency band covers the data link frequency band of the data link transmission module 20, so as to attenuate signals received by the RTK antenna within the data link frequency band, thereby reducing interference to RTK signal reception and processing.

[0032] Preferably, the first frequency band covers at least one of the 1430-1438MHz and 1438-1444MHz frequency ranges. For example, in an advantageous embodiment, the first frequency band may cover the 1300-1500MHz frequency range. 1430-1438MHz and 1438-1444MHz are two legally defined frequency ranges for image transmission, therefore, the data link frequency band of the data link transmission module 20 typically uses at least one of these two frequency ranges. According to embodiments of the invention, by selecting the first frequency band of the filtering circuit of the circuit device 12 to cover at least one of the 1430-1438MHz and 1438-1444MHz frequency ranges, interference from the image transmission signal of the data link transmission module 20 to RTK signal reception and processing can be specifically reduced, thereby reducing the risk of the RTK positioning system malfunctioning.

[0033] Furthermore, the filter circuit in circuit device 12 is preferably capable of conducting DC, allowing circuit device 12 to also function as part of the feed circuit for RTK antenna 11. This allows for greater flexibility in the placement of circuit device 12, preventing it from being limited in location due to obstructing the feed to the RTK antenna. On the other hand, the placement of the power supply (not shown) for the RTK antenna 11 can also be more flexible; for example, it can be installed away from the RTK antenna but closer to the RTK receiver, or even... Figure 1 It is set up together with the RTK receiver.

[0034] exist Figure 1In the example shown, in aircraft 1, circuit device 12 can be connected as a discrete circuit device between RTK antenna 11 and RTK receiver 13. In other embodiments, circuit device 12 can be integrated into RTK receiver 13; or, circuit device 12 can be integrated into RTK antenna 11 to form an RTK antenna device resistant to image transmission signal interference.

[0035] The circuit arrangement according to embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0036] Figure 2 This is a schematic circuit diagram of a circuit device 100 for an RTK antenna according to Embodiment 1 of the present invention. Figure 2 As shown, the circuit device 100 includes a filter circuit 100a, which includes a first LC circuit 110 and a second LC circuit 120. The first LC circuit 110 includes a first inductor L1 and a first capacitor C1 connected in parallel, for use with the RTK antenna 11 ( Figure 2 (Not shown in the diagram) Series connection. The second LC circuit 120 includes a second inductor L2 and a second capacitor C2 connected in series. The second LC circuit 120 is connected in parallel with the RTK antenna 11 via ground.

[0037] The inductance values ​​of the first inductor L1 and the second inductor L2, and the capacitance values ​​of the first capacitor C1 and the second capacitor C2, can be appropriately set according to the frequency band to be attenuated (i.e., the first frequency band). This is something that those skilled in the art can achieve based on common sense and experience, and will not be elaborated further here.

[0038] exist Figure 2 In the filter circuit 100a shown, the first LC circuit 110 includes an inductor and a capacitor connected in parallel, and the first LC circuit 110 is connected in series with the RTK antenna. This allows the filter circuit 100a to not only attenuate signals in a certain frequency band (the first frequency band), but also to conduct DC current to the RTK antenna 11. Thus, the filter circuit 100a can be used as part of the feed circuit of the RTK antenna 11, providing greater flexibility in the placement of the circuit device 100 and the RTK antenna feed power supply.

[0039] In the circuit device 100 according to Embodiment 1 of the present invention, preferably, as follows: Figure 2As shown, a short-circuit protection resistor R, connected in series with the filter circuit 100a, can be further included to prevent false short-circuit alarms. RTK circuits typically include short-circuit protection circuits to trigger protection when the current exceeds a certain current threshold, such as 150mA. Vibrations in aircraft, especially those of the generator in fuel-powered aircraft, can frequently cause momentary interruptions in connectors within the circuit, generating large momentary currents that trigger false short-circuit alarms from the short-circuit protection circuit. Therefore, the inventors of this invention propose adding a resistor to the circuitry used for RTK antennas to prevent momentary interruptions from being falsely reported as short circuits; this resistor is the short-circuit protection resistor R. According to an embodiment of the invention, the short-circuit protection resistor R has a specific resistance value to suppress the momentary current in the RTK antenna receiving circuit to a level below the current threshold that would trigger short-circuit protection.

[0040] For fixed-wing UAVs powered by fuel, it is particularly advantageous to set up a short-circuit protection resistor R to prevent transient false alarms. The resistance value of the short-circuit protection resistor R can be selected from 18 to 82 ohms, and preferably from 20 to 24 ohms.

[0041] In addition, such as Figure 2 As shown, the circuit arrangement 100 may further include a first connector J1 and a second connector J2 located at its two ends. The first connector J1 can be connected to an RTK antenna, and the second connector J2 can be connected to an RTK receiver. It should be understood that in other examples, the first connector J1 can be connected to an RTK receiver, and the second connector J2 can be connected to an RTK antenna, and the invention is not limited in this respect. The filter circuit 100a and the short-circuit resistor R (if present) for preventing transient false alarms are connected in series between the first connector and the second connector.

[0042] The first connector J1 and the second connector J2 preferably use SMA connectors (Sub Miniature version A) (i.e., the first SMA connector and the second SMA connector), especially flanged SMA connectors. The threaded connection of the SMA connector can effectively prevent circuit interruptions caused by turbulence and vibration during the flight of the aircraft 1, ensuring flight positioning. If the SMA connector has a flange, the flange helps to prevent nearby signals, such as image transmission signals, from coupling into the RTK antenna receiving circuit and blocking the receiver.

[0043] The following will refer to Figures 3 to 5 A circuit arrangement for an RTK antenna according to Embodiment 2 of the present invention is described.

[0044] Figure 3 This is a schematic diagram illustrating the relationship between the first frequency band, the second frequency band, and the third frequency band of the filter circuit in the circuit device 200 according to Embodiment 2 of the present invention; Figure 4This is a schematic block diagram of circuit device 200, which is an example of a circuit device according to Embodiment 2. Figure 5 This is another example of a circuit device according to Embodiment 2, namely a schematic block diagram of circuit device 200'.

[0045] As described above, according to embodiments of the present invention, it is desirable to prevent adverse effects of signals in the data link band of, for example, the data link transmission module on RTK signal reception and processing by attenuating signals in the first frequency band through a filtering circuit in a circuit arrangement that at least constitutes part of the RTK antenna receiving circuit. In the circuit arrangement according to a second embodiment of the present invention, the filtering circuit implements band-stop filtering in the first frequency band through two bandpass filters connected in parallel.

[0046] For example, see Figure 4 According to Embodiment 2, the circuit device 200 includes a filter circuit 200a, which includes a first bandpass filter 211 and a second bandpass filter 221 connected in parallel. The operating frequency bands of the first bandpass filter 211 and the second bandpass filter 221 are the second frequency band B2 and the third frequency band B3, respectively. The first frequency band B1 is located between the second frequency band B2 and the third frequency band B3 (see...). Figure 3 ).

[0047] Preferably, the minimum frequency value of the second frequency band B2 is greater than or equal to the maximum frequency value of the first frequency band B1, while the maximum frequency value of the third frequency band B3 is less than or equal to the minimum frequency value of the first frequency band B1. For example, if the first frequency band B1 is in the 1300-1450MHz frequency range, the circuit device 200 according to this embodiment is configured such that the minimum frequency value of the second frequency band B2 of the first bandpass filter 211 is greater than or equal to 1450MHz, while the maximum frequency value of the third frequency band B3 of the second bandpass filter 221 is less than or equal to 1300MHz.

[0048] According to this embodiment, by setting the conduction / operation frequency bands of the first bandpass filter 211 and the second bandpass filter 221 for the first frequency band covering the interference signal frequency band (e.g., the data link frequency band), the interference to RTK signal reception and processing is effectively reduced, especially avoiding the blocking of the RTK receiver by the aircraft's data link transmission module signal, thus ensuring the reliability of flight positioning.

[0049] It is worth noting that in the circuit device according to the embodiments of the present invention, the first bandpass filter and the second bandpass filter are not simply set according to the operating frequency of the RTK antenna itself. In order to avoid the data link frequency band used by, for example, the data link transmission module, some useful signals that are originally within the operating frequency range of the RTK antenna are lost after the above-mentioned first and second bandpass filters are set. However, it should be noted that due to the adjacent relationship between the data link transmission module and the RTK antenna and the high power characteristics of the data link transmission signal, the circuit device according to the embodiments of the present invention can effectively avoid RTK receiver saturation / blocking caused by the "influx" of data link transmission signals. Once the RTK receiver is saturated / blocked, the useful signals of the RTK antenna cannot be correctly received and processed, resulting in great risks. In other words, the circuit device according to the embodiments of the present invention ensures the reliability of RTK positioning at the cost of minimal signal loss, which is extremely beneficial to the flight safety of the aircraft.

[0050] For ease of understanding, the following will refer to Figure 4 An example of a circuit device 200 according to Embodiment 2 of the present invention is described. For example... Figure 4 As shown, the circuit device 200 includes a filter circuit 200a, which includes a first power divider 201, a second power divider 202, and a first bandpass filter 211 and a second bandpass filter 221 connected in parallel between the first power divider 201 and the second power divider 202. The first bandpass filter 211 is used to pass signals in the second frequency band B2, and the second bandpass filter 221 is used to pass signals in the third frequency band B3. The first frequency band B1 is located between the second frequency band B2 and the third frequency band B3.

[0051] Preferably, the filter circuit 200a may further include at least a DC-blocking inductor 230 connected in parallel with the first bandpass filter 211 and the second bandpass filter 221, so that the filter circuit 200a can conduct DC current to the RTK antenna 11, thereby enabling it to be used as part of the feed circuit of the RTK antenna 11, providing more flexibility in the placement of the circuit arrangement 200 and the RTK antenna feed power supply (not shown). Furthermore, using the inductor 230 to provide the feed path for the RTK antenna can also prevent useful RTK radio frequency signals from flowing away via the feed power supply.

[0052] Preferably, the first power divider 201 and the second power divider 202 are Wilkinson power dividers, so as not to obstruct the passage of DC current.

[0053] The first bandpass filter 211 and the second bandpass filter 221 can be, for example, surface acoustic filters.

[0054] exist Figure 4In the example shown, the filter circuit 200a further includes a first limiter 212 and a second limiter 222. The first limiter 212 and the first bandpass filter 211 are connected in series between the first power divider 201 and the second power divider 202, and the second limiter 222 and the second bandpass filter 221 are connected in series between the first power divider 201 and the second power divider 202. These limiters prevent high-power signals transmitted by the data link transmission module 20 from being conducted to the RTK receiver 13 through the RTK antenna 11, thus preventing receiver congestion.

[0055] Preferably, the first limiter 212 and the second limiter 222 are located closer to the RTK antenna relative to the first bandpass filter 211 and the second bandpass filter 221, respectively, thereby further protecting the bandpass filters. For example, some surface acoustic wave (SAW) filter products have a signal tolerance level of approximately 10 dBm, while the image transmission signal transmitted by the data link transmission module 20, after being coupled to the RTK antenna and possibly amplified in the RTK receiving circuit, may reach approximately 20 dBm; placing a limiter on the side of the bandpass filter closer to the RTK antenna can effectively prevent damage to the bandpass filter from, for example, excessively strong image transmission signals.

[0056] like Figure 4 As shown, similar to the circuit device 100 according to Embodiment 1 of the present invention, the circuit device 200 preferably further includes a short-circuit resistor R connected in series with the filter circuit 200a to prevent false alarms due to transient interruptions. For fixed-wing UAVs powered by fuel, the resistance value of the short-circuit resistor R can be selected from 18 to 82 ohms, and preferably from 20 to 24 ohms.

[0057] Furthermore, similar to the circuit device 100 according to Embodiment 1 of the present invention, the circuit device 200 may include a first connector J1 and a second connector J2 located at its two ends. Figure 4 In the example shown, the first connector J1 can be connected to an RTK receiver, and the second connector J2 can be connected to an RTK antenna. A filter circuit 200a and a short-circuit resistor R (if present) to prevent false short-circuit alarms are connected in series between the first connector J1 and the second connector J2. The first connector J1 and the second connector J2 are preferably SMA connectors, particularly flanged SMA connectors.

[0058] Figure 5 Another example of a circuit arrangement for an RTK antenna according to Embodiment 2 of the present invention is illustrated schematically, circuit arrangement 200'. Circuit arrangement 200' and Figure 4The circuit device 200 shown has a substantially the same structure, except that the two ends of the DC inductor 230 in the circuit device 200' are respectively connected to the outside of the first power divider 201 and the second power divider 202 (the side opposite to the bandpass filter), so as to be connected in parallel with the first power divider 201, the second power divider 202 and the circuit part connected between them (including the first bandpass filter 211 and the second bandpass filter 221).

[0059] Compared to circuit device 200, circuit device 200' does not have requirements or limitations on the "conversion" performance of the power dividers because the isolation DC inductor 230 is not connected between the two power dividers, thus providing more convenience for circuit design.

[0060] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A circuit arrangement for an RTK antenna, the circuit arrangement for connection to the RTK antenna and constituting at least a part of an antenna receiving circuit, wherein, The circuit device comprises a filter circuit capable of conducting direct current and capable of attenuating signals in a first frequency band, the first frequency band partially overlapping with an operating frequency band of the RTK antenna, and the first frequency band covering at least one of a 1430-1438 MHz frequency interval and a 1438-1444 MHz frequency interval; The filter circuit comprises a first power divider, a second power divider, a first band-pass filter and a second band-pass filter connected in parallel between the first power divider and the second power divider, and a blocking inductor connected in parallel with at least one of the first band-pass filter and the second band-pass filter, wherein the first band-pass filter is configured to pass signals in a second frequency band, and the second band-pass filter is configured to pass signals in a third frequency band, the first frequency band being between the second frequency band and the third frequency band.

2. The circuit arrangement of claim 1, wherein, A minimum frequency value of the second frequency band is greater than or equal to a maximum frequency value of the first frequency band, and a maximum frequency value of the third frequency band is less than or equal to a minimum frequency value of the first frequency band.

3. The circuit arrangement of claim 1, wherein, The first power divider and the second power divider are Wilkinson power dividers, and the first band-pass filter and the second band-pass filter are surface acoustic wave filters.

4. The circuit arrangement of claim 1, wherein, The filter circuit further comprises: a first limiter connected in series with the first band-pass filter between the first power divider and the second power divider; and a second limiter connected in series with the second band-pass filter between the first power divider and the second power divider.

5. The circuit arrangement of claim 4, wherein, The first limiter and the second limiter are respectively closer to the RTK antenna side relative to the first band-pass filter and the second band-pass filter.

6. The circuit arrangement of claim 1, wherein, The filter circuit comprises a first LC circuit and a second LC circuit, wherein the first LC circuit comprises a first inductor and a first capacitor connected in parallel, and is configured to be connected in series with the RTK antenna; the second LC circuit comprises a second inductor and a second capacitor connected in series, and is configured to be connected in parallel with the RTK antenna via a ground.

7. The circuit device of any one of claims 1-6, further comprising a transient-preventive false-short-circuit-resistor connected in series with the filter circuit, the transient-preventive false-short-circuit-resistor having a resistance value to suppress transient current in the circuit to a level below a current threshold capable of triggering a short-circuit protection.

8. The circuit arrangement of claim 7, wherein, The resistance value of the transient-preventive false-short-circuit-resistor is 18-82 ohms.

9. The circuit arrangement of claim 7, wherein, The resistance value of the transient-preventive false-short-circuit-resistor is 20-24 ohms.

10. The circuit device of claim 7, further comprising: a first SMA connector configured to be connected with the RTK antenna; and a second SMA connector configured to be connected with an RTK receiver for the RTK antenna, and the filter circuit and the transient-preventive false-short-circuit-resistor are connected in series between the first SMA connector and the second SMA connector.

11. An RTK receiver comprising the circuit device of any one of claims 1-10.

12. An RTK antenna apparatus comprising an RTK antenna and the circuit device of any one of claims 1-10 connected with the RTK antenna.

13. An aircraft comprising: ​ an RTK antenna; and a data link transmission module for transmitting images or data in a data link frequency band, the data link frequency band partially overlapping with an operating frequency band of the RTK antenna, wherein the aircraft further comprises a circuit arrangement according to any one of claims 1 to 10, and the first frequency band of the filter circuit of the circuit arrangement covers the data link frequency band.

14. The aircraft of claim 13, wherein, The aircraft further comprises an RTK receiver, and the circuit arrangement is connected between the RTK antenna and the RTK receiver, or integrated in the RTK antenna, or integrated in the RTK receiver.

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