Radio frequency signal processing circuit and antenna

Abstract

The invention relates to the technical field of antennas, and provides a radio-frequency signal processing circuit and an antenna, the radio-frequency signal processing circuit is electrically connected between a control module and an antenna module of unmanned equipment, on one hand, the radio-frequency signal processing circuit can separate radio-frequency signals with different frequencies from the control module and then send the radio-frequency signals to different antennas for emission, and on the other hand, the radio-frequency signals are transmitted to the antenna module; and on the other hand, radio frequency signals with different frequencies from different antennas can be fused and then sent to the control module, so that radio frequency signal transmission of different antennas can be realized only through one radio frequency connecting line.

Description

Technical Field

[0001] This application relates to the field of antenna technology, and more specifically, to a radio frequency signal processing circuit and an antenna. Background Technology

[0002] With the continuous advancement of autonomous driving technology and wireless communication technology, the operation of unmanned equipment has become more agile and efficient. At the same time, the means of communication with these devices have also become more diversified and advanced.

[0003] To improve the communication quality of unmanned equipment or to fulfill other functions, different communication modules are typically configured within the unmanned equipment. Each communication module is equipped with two antennas, a main one and a secondary one. For example... Figure 1 As shown, the unmanned equipment is equipped with a WIFI module and an RTK module. The RTK module is equipped with an RTK main antenna and an RTK secondary antenna connected by an RF coaxial cable, and the WIFI module is equipped with a WIFI main antenna and a WIFI secondary antenna connected by an RF coaxial cable. This requires 4 antennas and 4 RF coaxial cables, which not only occupies a lot of space in the unmanned equipment and increases the cost of the cables, but also the loss of RF signals by the cables will lead to the deterioration of RF performance.

[0004] Therefore, optimizing the antenna design in unmanned equipment and transmitting the radio frequency signals of different antennas through a single radio frequency connection line is a problem that needs to be considered. Summary of the Invention

[0005] The purpose of this application is to provide a radio frequency signal processing circuit and antenna that can transmit radio frequency signals from different antennas through a single radio frequency connection line.

[0006] To achieve the above objectives, the technical solutions adopted in the embodiments of this application are as follows:

[0007] In a first aspect, embodiments of this application provide a radio frequency signal processing circuit, which is electrically connected between the control module and the antenna module of an unmanned device, and includes a signal separation circuit, a signal processing circuit, an antenna working state switching circuit, and an antenna switching circuit. The antenna module includes a first antenna and a second antenna.

[0008] The signal separation circuit is electrically connected to the control module, the signal processing circuit, the antenna operating state switching circuit, and the antenna switching circuit, respectively, and is used to separate the uplink RF fusion signal from the control module into an uplink fusion signal, an antenna operating state switching signal, and an antenna switching signal, and then transmit them to the signal processing circuit, the antenna operating state switching circuit, and the antenna switching circuit, respectively.

[0009] The signal processing circuit is electrically connected to the first antenna and is used to separate the uplink fused signal into an uplink WIFI high-frequency signal and an uplink WIFI low-frequency signal, and transmit the uplink WIFI low-frequency signal to the first antenna for transmission.

[0010] The antenna operating state switching circuit is used to switch the current operating state of the second antenna according to the antenna operating state switching signal;

[0011] The second antenna includes multiple antenna elements, and the antenna switching circuit is electrically connected to each of the antenna elements. The antenna switching circuit is used to switch to a target antenna element among the multiple antenna elements that is suitable for the current communication conditions according to the antenna switching signal.

[0012] The signal processing circuit, the antenna operating state switching circuit, and the antenna switching circuit are electrically connected in sequence. The signal processing circuit is also used to transmit the separated uplink WIFI high-frequency signal to the target antenna unit for transmission when the current operating state of the second antenna is the transmission state and the antenna switching circuit is switched to the target antenna unit.

[0013] Optionally, the signal processing circuit is further configured to, when the current operating state of the second antenna is the receiving state and the antenna switching circuit is switched to the target antenna unit, fuse the downlink WIFI high-frequency signal from the target antenna unit and transmitted through the antenna switching circuit and the antenna operating state switching circuit, and the downlink fusion signal from the first antenna into a downlink radio frequency fusion signal and transmit it to the signal separation circuit, wherein the downlink fusion signal includes an RTK signal and a downlink WIFI low-frequency signal;

[0014] The signal separation circuit is also used to transmit the downlink RF fusion signal to the control module.

[0015] Optionally, the signal separation circuit includes a first multiplexing unit, the single-ended side of which is electrically connected to the control module, and the multi-ended side is electrically connected to the signal processing circuit, the antenna operating state switching circuit, and the antenna switching circuit, respectively.

[0016] The first multiplexing unit is used to separate the uplink RF fusion signal into an uplink fusion signal, an antenna operating state switching signal, and an antenna switching signal, and then transmit them to the signal processing circuit, the antenna operating state switching circuit, and the antenna switching circuit, respectively, and to transmit the downlink RF fusion signal to the control module.

[0017] Optionally, the signal processing circuit includes a second multiplexing unit, the single-ended side of which is electrically connected to the signal separation circuit, and the multi-ended side is electrically connected to the first antenna and the antenna operating state switching circuit, respectively.

[0018] The second multiplexing unit is used to separate the uplink fused signal into an uplink WIFI high-frequency signal and an uplink WIFI low-frequency signal, transmit the uplink WIFI low-frequency signal to the first antenna for transmission, and when the current operating state of the second antenna is the transmission state and the antenna switching circuit is switched to the target antenna unit, transmit the uplink WIFI high-frequency signal to the target antenna unit for transmission via the antenna operating state switching circuit and the antenna switching circuit;

[0019] The second multiplexing unit is further configured to, when the current operating state of the second antenna is the receiving state and the antenna switching circuit is switched to the target antenna unit, fuse the downlink WIFI high-frequency signal from the target antenna unit and transmitted through the antenna switching circuit and the antenna operating state switching circuit, and the downlink fusion signal from the first antenna into the downlink radio frequency fusion signal and transmit it to the signal separation circuit.

[0020] Optionally, the antenna operating state switching circuit includes a first switching control circuit and a first switching circuit. The first switching control circuit is electrically connected between the signal separation circuit and the first switching circuit, and the signal processing circuit, the first switching circuit and the antenna switching circuit are electrically connected in sequence.

[0021] The first switching control circuit is used to generate a first radio frequency control signal based on the antenna operating state switching signal, and to control the first switching circuit to switch the current operating state of the second antenna through the first radio frequency control signal.

[0022] Optionally, the first switching control circuit includes a third multiplexing unit, a first detection circuit, a first comparator, a second detection circuit, and a second comparator; the single-ended side of the third multiplexing unit is electrically connected to the signal separation circuit, and the multi-ended side is electrically connected to the first detection circuit and the second detection circuit, respectively; the input terminal of the first comparator is electrically connected to the first detection circuit, and the output terminal is electrically connected to the first switching circuit; the input terminal of the second comparator is electrically connected to the second detection circuit, and the output terminal is electrically connected to the first switching circuit.

[0023] The third multiplexing unit is used to separate the antenna operating state switching signal into a first radio frequency signal and a second radio frequency signal.

[0024] The first detection circuit is used to process the first radio frequency signal into a first DC voltage signal;

[0025] The second detection circuit is used to process the second radio frequency signal into a second DC voltage signal;

[0026] The first comparator is used to compare the first DC voltage signal with a reference voltage and output a transmit switch signal based on the comparison result;

[0027] The second comparator is used to compare the second DC voltage signal with a reference voltage and output a receive switch signal based on the comparison result;

[0028] The first radio frequency control signal includes the transmit switch signal and the receive switch signal.

[0029] Optionally, the first switching circuit includes a single-pole double-throw switch and an RF front-end unit. The input terminal of the single-pole double-throw switch is electrically connected to the output terminal of the signal processing circuit and the first comparator, respectively, and both output terminals are electrically connected to the RF front-end unit. The RF front-end unit is electrically connected to the antenna switching circuit, the output terminal of the first comparator, and the output terminal of the second comparator, respectively.

[0030] When the transmit switch signal is high and the receive switch signal is low, the single-pole double-throw switch switches to the transmit output point and the radio frequency front-end unit switches to the transmit state, so as to switch the current working state of the second antenna to the transmit state.

[0031] When the transmit switch signal is low and the receive switch signal is high, the single-pole double-throw switch switches to the receive output point and the radio frequency front-end unit switches to the receive state, so as to switch the current working state of the second antenna to the receive state.

[0032] Optionally, the antenna switching circuit includes a second switching control circuit and a second switching circuit. The second switching control circuit is electrically connected between the signal separation circuit and the second switching circuit. The second switching circuit is electrically connected to the antenna operating state switching circuit, and the second switching circuit is electrically connected to each of the antenna elements in the second antenna.

[0033] The second switching control circuit is used to generate a second radio frequency control signal based on the antenna switching signal, and to control the second switching circuit to switch to the target antenna unit that is suitable for the current communication conditions through the second radio frequency control signal.

[0034] Optionally, the second switching control circuit includes a signal processing unit, and the second switching circuit includes a single-pole four-way switch. The input terminal of the single-pole four-way switch is electrically connected to the signal processing unit and the antenna working state switching circuit, respectively, and the four output terminals are electrically connected to one of the antenna elements of the second antenna.

[0035] The signal processing unit is used to process the antenna switching signal into the second radio frequency control signal according to the signal strength between each second antenna and the external communication device;

[0036] The single-pole four-way switch is used to switch to the output point electrically connected to the target antenna unit with the strongest signal strength of the external communication device under the action of the second radio frequency control signal.

[0037] Secondly, embodiments of this application also provide an antenna, the antenna including the radio frequency signal processing circuit and antenna module described in the first aspect above, the antenna module including a first antenna and a second antenna;

[0038] The first antenna is used to transmit uplink low-frequency WIFI signals and receive RTK signals and downlink low-frequency WIFI signals;

[0039] The second antenna includes multiple antenna elements, which are used to transmit uplink WIFI high-frequency signals and receive downlink WIFI high-frequency signals under the switching control of the radio frequency signal processing circuit.

[0040] Compared to existing technologies, this application provides a radio frequency signal processing circuit and antenna. The radio frequency signal processing circuit is electrically connected between the control module and the antenna module of the unmanned equipment. It includes a signal separation circuit, a signal processing circuit, an antenna operating state switching circuit, and an antenna switching circuit. The antenna module includes a first antenna and a second antenna. The signal separation circuit separates the uplink RF fusion signal from the control module into an uplink fusion signal, an antenna operating state switching signal, and an antenna switching signal, and then transmits them to the signal processing circuit, the antenna operating state switching circuit, and the antenna switching circuit, respectively. The signal processing circuit separates the uplink fusion signal into an uplink WIFI high-frequency signal and an uplink WIFI low-frequency signal, and transmits the uplink WIFI low-frequency signal to the first antenna for transmission. At the same time, when the current operating state of the second antenna is the transmission state and the antenna switching circuit is switched to the target antenna unit, the uplink WIFI high-frequency signal is transmitted to the target antenna unit for transmission via the antenna operating state switching circuit and the antenna switching circuit. That is, on the one hand, it can separate radio frequency signals of different frequencies from the control module and send them to different antennas for transmission; on the other hand, it can fuse radio frequency signals of different frequencies from different antennas and send them to the control module, so that radio frequency signal transmission from different antennas can be achieved through only one radio frequency connection line. Attached Figure Description

[0041] Figure 1 A schematic diagram of the structure of an antenna provided by the prior art is shown.

[0042] Figure 2 This application provides a schematic diagram of the structure of a radio frequency signal processing circuit according to an embodiment. Figure 1 .

[0043] Figure 3 This application provides a schematic diagram of the structure of a radio frequency signal processing circuit according to an embodiment. Figure 2 .

[0044] Figure 4 This application provides a schematic diagram of the structure of a radio frequency signal processing circuit according to an embodiment. Figure 3 .

[0045] Figure 5 This application provides a schematic diagram of the structure of a radio frequency signal processing circuit according to an embodiment. Figure 4 .

[0046] Figure 6 A schematic diagram of an antenna structure provided in an embodiment of this application is shown.

[0047] Figure 7 A schematic diagram of the structure of a first antenna provided in an embodiment of this application is shown.

[0048] Figure 8 A schematic diagram of the structure of a second antenna provided in an embodiment of this application is shown.

[0049] Figure 9 A schematic diagram of an antenna system provided in an embodiment of this application is shown.

[0050] Icons: 10-RF signal processing circuit; 11-Signal separation circuit; 12-Signal processing circuit; 13-Antenna operating state switching circuit; 14-Antenna switching circuit; 111-First multiplexing unit; 121-Second multiplexing unit; 131-First switching control circuit; 132-First switching circuit; 141-Second switching control circuit; 142-Second switching circuit; 1311-Third multiplexing unit; 1312-First detector circuit; 1313-First comparator; 1314-Second detector circuit; 1315-Second comparator; 1321 - Single-pole double-throw switch; 1322-RF front-end unit; 1411-Signal processing unit; 1421-Single-pole four-way switch; 20-First antenna; 30-Second antenna; 211-RTK antenna; 212-Low-pass filter; 213-First low-noise amplifier; 214-First GNSS duplexer; 215-High-frequency GNSS surface acoustic wave filter; 216-Low-frequency GNSS surface acoustic wave filter; 217-Second GNSS duplexer; 218-Second low-noise amplifier; 221-LTCC duplexer; 222-Low-frequency WIFI antenna. Detailed Implementation

[0051] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.

[0052] To optimize antenna design in unmanned equipment, radio frequency signals from different antennas are transmitted through a single radio frequency connection cable. Please refer to [reference needed]. Figure 2 This application provides a radio frequency (RF) signal processing circuit 10, which is electrically connected between the control module and the antenna module of an unmanned device. On one hand, it separates RF signals of different frequencies from the control module and sends them to different antennas for transmission. On the other hand, it can fuse RF signals of different frequencies from different antennas and send them to the control module, thus enabling RF signal transmission from different antennas to be achieved through only one RF connection line. A detailed description follows.

[0053] In this embodiment, radio frequency (RF) signals of different frequencies from the control module and from different antennas can be fused using modulation and demodulation techniques, and then transmitted through a single RF connection line. The RF signals of different frequencies from the control module may include: high-frequency and low-frequency Wi-Fi signals sent by the control module to the external communication device. The RF signals of different frequencies from different antennas may include: RTK signals, high-frequency Wi-Fi signals, and low-frequency Wi-Fi signals sent by the external communication device to the control module.

[0054] In this embodiment, different radio frequency (RF) signals can correspond to different frequency ranges. The frequency range corresponding to the RTK signal can be: low frequency (L2+L5) 1164MHz~1286MHz, high frequency (L1) 1559MHz~1591MHz, for example, RTK 1.2G RF signal and RTK 1.5G RF signal. The frequency range corresponding to the high frequency WIFI signal can be 5150MHz~5850MHz, for example, WIFI 5.8G RF signal. The frequency range corresponding to the low frequency WIFI signal can be 2400MHz~2500MHz, for example, WIFI 2.4G RF signal.

[0055] Please refer to Figure 3 The radio frequency signal processing circuit 10 includes a signal separation circuit 11, a signal processing circuit 12, an antenna operating state switching circuit 13, and an antenna switching circuit 14.

[0056] The signal separation circuit 11 is electrically connected to the control module, the signal processing circuit 12, the antenna operating state switching circuit 13, and the antenna switching circuit 14, respectively. It is used to separate the uplink RF fusion signal from the control module into an uplink fusion signal, an antenna operating state switching signal, and an antenna switching signal, and then transmit them to the signal processing circuit 12, the antenna operating state switching circuit 13, and the antenna switching circuit 14, respectively.

[0057] In this embodiment, the uplink fusion signal may include a high-frequency WIFI signal (e.g., a WIFI 5.8G radio frequency signal) and a low-frequency WIFI signal (e.g., a WIFI 2.4G radio frequency signal) sent by the control module to the external communication device.

[0058] The signal processing circuit 12 is electrically connected to the first antenna and is used to separate the uplink fused signal into an uplink WIFI high-frequency signal and an uplink WIFI low-frequency signal, and transmit the uplink WIFI low-frequency signal to the first antenna for transmission.

[0059] In this embodiment, the uplink WIFI high-frequency signal can be the WIFI 5.8G radio frequency signal sent by the control module to the external communication device, and the uplink WIFI low-frequency signal can be the WIFI 2.4G radio frequency signal sent by the control module to the external communication device.

[0060] The antenna operating state switching circuit 13 is used to switch the current operating state of the second antenna according to the antenna operating state switching signal.

[0061] The antenna switching circuit 14 is electrically connected to each antenna element in the second antenna. The antenna switching circuit 14 is used to switch to the target antenna element among the multiple antenna elements that is suitable for the current communication conditions according to the antenna switching signal.

[0062] The antenna module includes a first antenna and a second antenna. The radio frequency signal processing circuit 10 is connected to the first antenna via a radio frequency coaxial cable, and the radio frequency signal processing circuit 10 is connected to the second antenna via a radio frequency coaxial cable.

[0063] The first antenna is used to transmit low-frequency Wi-Fi signals from the control module and to receive low-frequency Wi-Fi signals and RTK signals from external communication devices. The second antenna is used to transmit high-frequency Wi-Fi signals from the control module and to receive high-frequency Wi-Fi signals from external communication devices.

[0064] The second antenna can operate in either a transmitting or receiving state. It can include at least two antenna elements facing different directions. The target antenna element can be the one with the strongest signal strength to the external communication device among all antenna elements. This ensures that the antenna element with the strongest signal strength to the external communication device is always selected for transmitting and receiving WIFI 5.8G radio frequency signals, resulting in a significant enhancement of the equivalent omnidirectional radiation power of the WIFI 5.8G radio frequency signal and a substantial increase in the maximum communication distance.

[0065] Meanwhile, the signal processing circuit 12, the antenna working state switching circuit 13, and the antenna switching circuit 14 are electrically connected in sequence. The signal processing circuit 12 is also used to transmit the separated uplink WIFI high-frequency signal to the target antenna unit for transmission when the current working state of the second antenna is the transmission state and the antenna switching circuit 14 is switched to the target antenna unit.

[0066] In this embodiment, the signal processing circuit 12 is further configured to, when the current working state of the second antenna is the receiving state and the antenna switching circuit 14 is switched to the target antenna unit, fuse the downlink WIFI high-frequency signal from the target antenna unit and transmitted through the antenna switching circuit 14 and the antenna working state switching circuit 13 and the downlink fusion signal from the first antenna into a downlink radio frequency fusion signal and transmit it to the signal separation circuit 11. The downlink fusion signal includes an RTK signal and a downlink WIFI low-frequency signal.

[0067] The signal separation circuit 11 is also used to transmit the downlink RF fusion signal to the control module.

[0068] In this embodiment, the downlink WIFI high-frequency signal can be the WIFI 5.8G radio frequency signal sent by the external communication device to the control module, and the downlink WIFI low-frequency signal can be the WIFI 2.4G radio frequency signal sent by the external communication device to the control module.

[0069] Please refer to Figure 4The signal separation circuit 11 may include a first multiplexing unit 111. The single-ended side of the first multiplexing unit 111 is connected to the control module, and the multi-ended side is electrically connected to the signal processing circuit 12, the antenna working state switching circuit 13, and the antenna switching circuit 14, respectively.

[0070] The first multiplexing unit 111 is used to separate the uplink RF fusion signal into an uplink fusion signal, an antenna operating state switching signal, and an antenna switching signal, and then transmit them to the signal processing circuit 12, the antenna operating state switching circuit 13, and the antenna switching circuit 14, respectively, and to transmit the downlink RF fusion signal to the control module.

[0071] In this embodiment, the first multiplexing unit 111 can be an LC duplexer, which can use inductors (L) and capacitors (C) to achieve signal frequency separation. That is, the LC duplexer uses inductors (L) and capacitors (C) to separate the uplink RF fusion signal into an uplink fusion signal, an antenna operating state switching signal, and an antenna switching signal based on the different frequencies of the various RF signals. For example, the uplink fusion signal may include RF signals with frequencies ranging from 5150MHz to 5850MHz and 2400MHz to 2500MHz, the antenna operating state switching signal may be an RF signal with a frequency of 433MHz, and the antenna switching signal may include RF signals with frequencies of 26MHz and 40MHz. By using an LC duplexer, the loss of RF signals at different frequencies can be reduced. For example, the loss of the WIFI band RF signal (i.e., the uplink fusion signal) is less than 0.6dB, the loss of the antenna operating state switching signal is less than 1.2dB, and the loss of the antenna switching signal is less than 1dB.

[0072] Please refer to this again. Figure 4 The signal processing circuit 12 may include a second multiplexing unit 121. The single-ended side of the second multiplexing unit 121 is electrically connected to the signal separation circuit 11, and the multi-ended side is electrically connected to the first antenna and the antenna operating state switching circuit 13, respectively.

[0073] The second multiplexing unit 121 is used to separate the uplink fused signal into an uplink WIFI high-frequency signal and an uplink WIFI low-frequency signal, transmit the uplink WIFI low-frequency signal to the first antenna for transmission, and when the current working state of the second antenna is the transmission state and the antenna switching circuit 14 is switched to the target antenna unit, transmit the uplink WIFI high-frequency signal to the target antenna unit for transmission via the antenna working state switching circuit 13 and the antenna switching circuit 14.

[0074] The second multiplexing unit 121 is also used to, when the current working state of the second antenna is the receiving state and the antenna switching circuit 14 is switched to the target antenna unit, fuse the downlink WIFI high-frequency signal from the target antenna unit and transmitted through the antenna switching circuit 14 and the antenna working state switching circuit 13, and the downlink fusion signal from the first antenna into a downlink RF fusion signal and transmit it to the signal separation circuit 11.

[0075] In this embodiment, the second multiplexing unit 121 can be an LTCC duplexer. An LTCC duplexer utilizes Low-Temperature Co-fired Ceramic (LTCC) technology to integrate passive components with different functions onto a multilayer ceramic substrate, achieving effective signal separation and processing. Specifically, the LTCC duplexer separates the uplink fused signal into an uplink high-frequency Wi-Fi signal and an uplink low-frequency Wi-Fi signal based on the different frequencies of each radio frequency signal. For example, the uplink high-frequency Wi-Fi signal can be a radio frequency signal with a frequency range of 5150MHz to 5850MHz (i.e., Wi-Fi 5.8G radio frequency signal), and the uplink low-frequency Wi-Fi signal can be a radio frequency signal with a frequency range of 2400MHz to 2500MHz (i.e., Wi-Fi 2.4G radio frequency signal).

[0076] Please refer to this again. Figure 4 The antenna operating state switching circuit 13 includes a first switching control circuit 131 and a first switching circuit 132. The first switching control circuit 131 is electrically connected between the signal separation circuit 11 and the first switching circuit 132, and the signal processing circuit 12, the first switching circuit 132 and the antenna switching circuit 14 are electrically connected in sequence.

[0077] The first switching control circuit 131 is used to generate a first radio frequency control signal based on the antenna working state switching signal, and control the first switching circuit 132 to switch the current working state of the second antenna through the first radio frequency control signal.

[0078] Please refer to Figure 5 The first switching control circuit 131 includes a third multiplexing unit 1311, a first detection circuit 1312, a first comparator 1313, a second detection circuit 1314, and a second comparator 1315. The single-ended side of the third multiplexing unit 1311 is electrically connected to the signal separation circuit 11, and the multi-ended side is electrically connected to the first detection circuit 1312 and the second detection circuit 1314, respectively. The input terminal of the first comparator 1313 is electrically connected to the first detection circuit 1312, and the output terminal is electrically connected to the first switching circuit 132. The input terminal of the second comparator 1315 is electrically connected to the second detection circuit 1314, and the output terminal is electrically connected to the first switching circuit 132.

[0079] The third multiplexing unit 1311 is used to separate the antenna operating state switching signal into a first radio frequency signal and a second radio frequency signal;

[0080] The first detector circuit 1312 is used to process the first radio frequency signal into a first DC voltage signal;

[0081] The second detection circuit 1314 is used to process the second radio frequency signal into a second DC voltage signal;

[0082] The first comparator 1313 is used to compare the first DC voltage signal with the reference voltage and output a transmit switch signal according to the comparison result;

[0083] The second comparator 1315 is used to compare the second DC voltage signal with the reference voltage and output a receive switch signal according to the comparison result;

[0084] The first radio frequency control signal includes a transmit switch signal and a receive switch signal.

[0085] In this embodiment, the third multiplexing unit 1311 can be an LC duplexer. The LC duplexer separates the antenna operating state switching signal into a first RF signal and a second RF signal according to the different frequencies of the various RF signals. For example, the first RF signal can be a 26MHz RF signal, and the second RF signal can be a 40MHz RF signal.

[0086] The transmitting switch signal has two states: high and low. If the first DC voltage signal is less than the reference voltage, the transmitting switch signal is low; if the first DC voltage signal is greater than the reference voltage, the transmitting switch signal is high. Similarly, the receiving switch signal also has two states: high and low. If the second DC voltage signal is less than the reference voltage, the receiving switch signal is low; if the first DC voltage signal is greater than the reference voltage, the receiving switch signal is high. A high level can be represented as 1, and a low level can be represented as 0.

[0087] Please refer to this again. Figure 5 The first switching circuit 132 includes a single-pole double-throw switch 1321 and an RF front-end unit 1322. The input terminal of the single-pole double-throw switch 1321 is electrically connected to the output terminal of the signal processing circuit 12 and the first comparator 1313, respectively. Both output terminals are electrically connected to the RF front-end unit 1322. The RF front-end unit 1322 is electrically connected to the antenna switching circuit 14, the output terminal of the first comparator 1313, and the output terminal of the second comparator 1315, respectively.

[0088] When the transmit switch signal is high and the receive switch signal is low, the single-pole double-throw switch 1321 switches to the transmit output point and the radio frequency front-end unit 1322 switches to the transmit state, so as to switch the current working state of the second antenna to the transmit state.

[0089] When the transmit switch signal is low and the receive switch signal is high, the single-pole double-throw switch 1321 switches to the receive output point and the RF front-end unit 1322 switches to the receive state, so as to switch the current working state of the second antenna to the receive state.

[0090] In this embodiment, the transmit switch signal is used to control the single-pole double-throw switch 1321 to switch its output point. When the transmit switch signal is 1, the single-pole double-throw switch 1321 switches to the transmit output point; when the transmit switch signal is 0, the single-pole double-throw switch 1321 switches to the receive output point. The single-pole double-throw switch 1321 can be an SPDT RF switch.

[0091] Meanwhile, the transmit switch signal and the receive switch signal are combined to control the switching of the working state of the RF front-end unit 1322. The RF front-end unit 1322 can have four working states: transmit, receive, bypass, and off. When the transmit switch signal is 1 and the receive switch signal is 0, the RF front-end unit 1322 switches to the transmit state. When the transmit switch signal is 0 and the receive switch signal is 1, the RF front-end unit 1322 switches to the receive state. When the transmit switch signal is 0 and the receive switch signal is 0, the RF front-end unit 1322 switches to the bypass state. When the transmit switch signal is 1 and the receive switch signal is 1, the RF front-end unit 1322 switches to the off state.

[0092] Please refer to this again. Figure 4 The antenna switching circuit 14 includes a second switching control circuit 141 and a second switching circuit 142. The second switching control circuit 141 is electrically connected between the signal separation circuit 11 and the second switching circuit 142. The second switching circuit 142 is electrically connected to the antenna operating state switching circuit 13, and the second switching circuit 142 is electrically connected to each antenna element in the second antenna.

[0093] The second switching control circuit 141 is used to generate a second radio frequency control signal based on the antenna switching signal, and control the second switching circuit to switch to the target antenna unit suitable for the current communication conditions through the second radio frequency control signal.

[0094] Please refer to this again. Figure 5 The second switching control circuit 141 includes a signal processing unit 1411, and the second switching circuit 142 includes a single-pole four-way switch 1421. The input terminals of the single-pole four-way switch 1421 are electrically connected to the signal processing unit 1411 and the antenna working state switching circuit 13, respectively, and the four output terminals are electrically connected to one of the antenna units of the second antenna.

[0095] The signal processing unit 1411 is used to process the antenna switching signal into a second radio frequency control signal based on the signal strength between each second antenna and the external communication device;

[0096] The single-pole four-way switch 1421 is used to switch to the output point of the target antenna unit with the strongest signal strength to the external communication equipment under the action of the second radio frequency control signal.

[0097] In this embodiment, each antenna element can periodically return its signal strength with the external communication device to the signal processing unit 1411. Based on the signal strength, the signal processing unit 1411 processes the antenna switching signal into a second radio frequency control signal. This second radio frequency control signal controls the single-pole four-way switch 1421 to switch to the output point connected to the antenna element with the strongest signal strength. The single-pole four-way switch 1421 can be an SP4T radio frequency switch.

[0098] The second radio frequency control signal may include two switching signals, which are respectively transmitted through... Figure 5 The signal processing unit 1411 transmits data via two connecting lines to the single-pole four-way switch 1421. These two switch signals each have two states: high level 1 and low level 0, resulting in four possible combinations: 00, 01, 10, and 11. These states control the connection of the single-pole four-way switch 1421. Figure 5 The output points of the four antenna elements in the second antenna can be used to dynamically select the directional antenna, ensuring that the antenna element with the strongest signal strength between the second antenna and the external communication equipment is always selected to transmit and receive WIFI 5.8G radio frequency signals. This results in a significant enhancement of the equivalent omnidirectional radiation power of the WIFI 5.8G radio frequency signal and a significant increase in the maximum communication distance.

[0099] Please refer to Figure 6 This application also provides an antenna, which includes a radio frequency signal processing circuit 10 and an antenna module. The antenna module includes a first antenna 20 and a second antenna 30. The first antenna 20 is used to transmit uplink low-frequency Wi-Fi signals and receive RTK signals and downlink low-frequency Wi-Fi signals. The second antenna 30 includes multiple antenna elements, which are used to transmit uplink high-frequency Wi-Fi signals and receive downlink high-frequency Wi-Fi signals under the switching control of the radio frequency signal processing circuit.

[0100] In this embodiment, the first antenna 20 may include an RTK board and a WIFI board, which are electrically connected via a gold finger connector, and the WIFI board is electrically connected to the radio frequency signal processing circuit 10.

[0101] The WIFI board is used to receive uplink low-frequency WIFI signals and transmit them.

[0102] The RTK board is used to receive RTK signals from external communication devices and transmit the RTK signals to the WIFI board;

[0103] The WIFI board is also used to fuse the RTK signal and the downlink WIFI low-frequency signal from the external communication device into a downlink fused signal before transmitting it to the radio frequency signal processing circuit 10.

[0104] In this embodiment, the WIFI board includes a WIFI 2.4G antenna, and the RTK board includes an RTK antenna. The first antenna integrates the WIFI 2.4G antenna and the RTK antenna. By using a gold finger connector to connect the RTK antenna and the WIFI 2.4G antenna instead of a radio frequency connection cable, signal loss and interference can be effectively reduced, ensuring stable signal transmission.

[0105] Please refer to Figure 7 The RTK board may include an RTK antenna 211, a low-pass filter 212, a first low-noise amplifier 213, a first GNSS duplexer 214, a high-frequency GNSS surface acoustic wave filter 215, a low-frequency GNSS surface acoustic wave filter 216, a second GNSS duplexer 217, and a second low-noise amplifier 218.

[0106] The single-ended sides of the RTK antenna 211, low-pass filter 212, first low-noise amplifier 213, and first GNSS duplexer 214 are electrically connected in sequence. The multi-ended side of the first GNSS duplexer 214 is electrically connected to the high-frequency GNSS surface acoustic wave filter 215 and the low-frequency GNSS surface acoustic wave filter 216, respectively. The high-frequency GNSS surface acoustic wave filter 215 and the low-frequency GNSS surface acoustic wave filter 216 are both electrically connected to the multi-ended side of the second GNSS duplexer 217. The single-ended side of the second GNSS duplexer 217 is electrically connected to the second low-noise amplifier 218. The second low-noise amplifier 218 is electrically connected to the WIFI board through a gold finger connector.

[0107] In this embodiment, the RTK antenna 211 receives RTK signals from an external communication device. The frequency range corresponding to the RTK signal may include: low frequency (L2+L5) 1164MHz~1286MHz, high frequency (L1) 1559MHz~1591MHz, that is, including RTK 1.2G radio frequency signals and RTK 1.5G radio frequency signals.

[0108] Low-pass filter 212 is used to remove high-frequency noise and interference from the RTK signal. First low-noise amplifier 213, also denoted as LAN1, is used to amplify the received RTK signal while minimizing the introduction of additional noise. Since the RTK signal includes RTK 1.2G and RTK 1.5G radio frequency signals, to improve signal processing accuracy, the RTK signal is first separated into RTK 1.5G and RTK 1.2G radio frequency signals by first GNSS duplexer 214, and then input to high-frequency GNSS surface acoustic wave (SAW) filter 215 and low-frequency GNSS SAW filter 216 respectively to effectively suppress interference and noise in undesirable frequency bands. Afterwards, the processed RTK 1.5G and RTK 1.2G radio frequency signals are combined by second GNSS duplexer 217, and further amplified by second low-noise amplifier 218 to obtain the final RTK signal, which is then transmitted to the WIFI board via the gold finger connector.

[0109] Please refer to this again. Figure 7 The WIFI board includes an LTCC duplexer 221 and a low-frequency WIFI antenna 222. The multi-ended side of the LTCC duplexer 221 is connected to the low-frequency WIFI antenna 222 and is connected to the RTK board through a gold finger connector. The single-ended side of the LTCC duplexer 221 is connected to the radio frequency signal processing circuit 10.

[0110] The LTCC duplexer 221 is used to fuse the RTK signal transmitted by the RTK board and the downlink WIFI low-frequency signal transmitted by the low-frequency WIFI antenna 222 into a downlink fused signal, which is then transmitted to the radio frequency signal processing circuit 10.

[0111] In this embodiment, the RTK board adopts an active circuit design, which can achieve an in-band gain of more than 20dB. At the same time, it integrates a GNSS high and low frequency duplexer and a GNSS surface acoustic wave filter, which can achieve an out-of-band rejection of more than 30dB, thus improving the anti-interference performance of the dual-frequency RTK.

[0112] In the existing technology, the design of WIFI antennas and RTK antennas on unmanned devices, in addition to requiring 4 antennas and 4 radio frequency coaxial cables as mentioned above, also uses an omnidirectional antenna design for WIFI antennas. Although the omnidirectional antenna design can provide 360-degree signal coverage on the horizontal plane, allowing wireless signals to propagate evenly in all directions, its low gain results in limited radiated power, which limits the overall WIFI performance and communication distance of the device.

[0113] To solve this problem, please refer to Figure 8 In this embodiment, the second antenna may include four antenna elements facing different directions. The four antenna elements form a tetrahedron and are fixed to the radio frequency signal processing circuit 10.

[0114] In this embodiment, the antenna unit can be a WIFI 5.8G antenna. By designing four WIFI 5.8G antennas facing different directions, the antenna gain is improved. Compared with the traditional single omnidirectional antenna, each WIFI 5.8G antenna has a gain improvement of at least 5dB, realizing the design of a high-gain directional antenna. At the same time, the four-sided switching scheme can realize the dynamic selection of the working antenna according to the signal strength between each WIFI 5.8G antenna and the external communication device, ensuring that the unmanned equipment can achieve the best antenna radiation effect in any position.

[0115] Please refer to Figure 9 This application also provides an antenna system, which includes a main antenna, a secondary antenna, and a control module. The main antenna and the secondary antenna have the same structure and both include... Figure 6 The diagram shows a radio frequency signal processing circuit 10, a first antenna 20, and a second antenna 30. The control module includes a main combiner, a secondary combiner, an RTK module, a WIFI module, a first control module, and a second control module. The main combiner is electrically connected to the main antenna, the secondary combiner is electrically connected to the secondary antenna, and both the main combiner and the secondary combiner are electrically connected to the RTK module and the WIFI module. Both the first control module and the second control module are also electrically connected to the RTK module and the WIFI module.

[0116] The main combiner is used to combine WIFI signals from different frequency bands from the WIFI module, antenna operating state switching signals from the first control module, and antenna switching signals from the second control module into an uplink RF fusion signal and transmit it to the main antenna. It also receives the downlink RF fusion signal sent by the main antenna and separates the downlink RF fusion signal into RTK signals and WIFI signals from different frequency bands and transmits them to the RTK module and the WIFI module respectively.

[0117] The secondary combiner is used to fuse WIFI signals from different frequency bands from the WIFI module, antenna operating state switching signals from the first control module, and antenna switching signals from the second control module into an uplink RF fusion signal and transmit it to the secondary antenna. It also receives the downlink RF fusion signal sent by the secondary antenna and separates the downlink RF fusion signal into an RTK signal and WIFI signals from different frequency bands and transmits them to the RTK module and the WIFI module respectively.

[0118] In this embodiment, when the main antenna is operating, the uplink and downlink RF fusion signals are transmitted through the main combiner. When the secondary antenna is operating, the uplink and downlink RF fusion signals are transmitted through the secondary combiner. When both the main and secondary antennas are operating simultaneously, the uplink and downlink RF fusion signals are transmitted through the main and secondary combiners, respectively. Simultaneously, the main and secondary antennas can periodically return their signal strength with external communication devices to the control module, which then selects the operating antenna based on the signal strength.

[0119] The first control module is used to generate an antenna operating state switching signal and transmit it to the main combiner and / or the sub combiner. The antenna operating state switching signal is used to indicate the main antenna and / or the sub antenna to switch the current operating state of the second antenna 30.

[0120] The second control module is used to generate an antenna switching signal and transmit it to the main combiner and / or the sub combiner. The antenna switching signal is used to instruct the main antenna and / or the sub antenna to switch to the target antenna element in the second antenna 30 that is suitable for the current communication conditions.

[0121] In this embodiment, the first control module is a 433MHz module, and the antenna operating state switching signal is a 433MHz frequency signal. The second control module includes a 26MHz crystal oscillator and a 40MHz crystal oscillator, and the antenna switching signal includes a 26MHz frequency signal and a 40MHz frequency signal.

[0122] This application embodiment also provides an unmanned device, the unmanned device including... Figure 9 The antenna system shown is an example of an unmanned device. Unmanned equipment can be, but is not limited to, drones, unmanned vehicles, unmanned ships, autopilots, etc., and this embodiment does not impose any limitations on this.

[0123] In summary, this application provides a radio frequency signal processing circuit and an antenna. The radio frequency signal processing circuit is electrically connected between the control module and the antenna module of an unmanned device. It includes a signal separation circuit, a signal processing circuit, an antenna operating state switching circuit, and an antenna switching circuit. The antenna module includes a first antenna and a second antenna. The signal separation circuit separates the uplink RF fusion signal from the control module into an uplink fusion signal, an antenna operating state switching signal, and an antenna switching signal, and then transmits them to the signal processing circuit, the antenna operating state switching circuit, and the antenna switching circuit, respectively. The signal processing circuit separates the uplink fusion signal into an uplink WIFI high-frequency signal and an uplink WIFI low-frequency signal, and transmits the uplink WIFI low-frequency signal to the first antenna for transmission. At the same time, when the current operating state of the second antenna is the transmission state and the antenna switching circuit is switched to the target antenna unit, the uplink WIFI high-frequency signal is transmitted to the target antenna unit for transmission via the antenna operating state switching circuit and the antenna switching circuit. That is, on the one hand, it can separate radio frequency signals of different frequencies from the control module and send them to different antennas for transmission; on the other hand, it can fuse radio frequency signals of different frequencies from different antennas and send them to the control module, so that radio frequency signal transmission from different antennas can be achieved through only one radio frequency connection line.

[0124] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A radio frequency signal processing circuit, characterized in that, The radio frequency signal processing circuit is electrically connected between the control module and the antenna module of the unmanned equipment, and includes a signal separation circuit, a signal processing circuit, an antenna working state switching circuit and an antenna switching circuit. The antenna module includes a first antenna and a second antenna. The signal separation circuit is electrically connected to the control module, the signal processing circuit, the antenna operating state switching circuit, and the antenna switching circuit, respectively, and is used to separate the uplink RF fusion signal from the control module into an uplink fusion signal, an antenna operating state switching signal, and an antenna switching signal, and then transmit them to the signal processing circuit, the antenna operating state switching circuit, and the antenna switching circuit, respectively. The signal processing circuit is electrically connected to the first antenna and is used to separate the uplink fused signal into an uplink WIFI high-frequency signal and an uplink WIFI low-frequency signal, and transmit the uplink WIFI low-frequency signal to the first antenna for transmission. The antenna operating state switching circuit is used to switch the current operating state of the second antenna according to the antenna operating state switching signal; The second antenna includes multiple antenna elements, and the antenna switching circuit is electrically connected to each of the antenna elements. The antenna switching circuit is used to switch to a target antenna element among the multiple antenna elements that is suitable for the current communication conditions according to the antenna switching signal. The signal processing circuit, the antenna operating state switching circuit, and the antenna switching circuit are electrically connected in sequence. The signal processing circuit is also used to transmit the separated uplink WIFI high-frequency signal to the target antenna unit for transmission when the current operating state of the second antenna is the transmission state and the antenna switching circuit is switched to the target antenna unit.

2. The radio frequency signal processing circuit as described in claim 1, characterized in that, The signal processing circuit is further configured to, when the current operating state of the second antenna is the receiving state and the antenna switching circuit is switched to the target antenna unit, fuse the downlink WIFI high-frequency signal from the target antenna unit and transmitted through the antenna switching circuit and the antenna operating state switching circuit, and the downlink fusion signal from the first antenna into a downlink radio frequency fusion signal and transmit it to the signal separation circuit, wherein the downlink fusion signal includes an RTK signal and a downlink WIFI low-frequency signal; The signal separation circuit is also used to transmit the downlink RF fusion signal to the control module.

3. The radio frequency signal processing circuit as described in claim 2, characterized in that, The signal separation circuit includes a first multiplexing unit. The single-ended side of the first multiplexing unit is electrically connected to the control module, and the multi-ended side is electrically connected to the signal processing circuit, the antenna operating state switching circuit, and the antenna switching circuit, respectively. The first multiplexing unit is used to separate the uplink RF fusion signal into an uplink fusion signal, an antenna operating state switching signal, and an antenna switching signal, and then transmit them to the signal processing circuit, the antenna operating state switching circuit, and the antenna switching circuit, respectively, and to transmit the downlink RF fusion signal to the control module.

4. The radio frequency signal processing circuit as described in claim 2, characterized in that, The signal processing circuit includes a second multiplexing unit. The single-ended side of the second multiplexing unit is electrically connected to the signal separation circuit, and the multi-ended side is electrically connected to the first antenna and the antenna operating state switching circuit, respectively. The second multiplexing unit is used to separate the uplink fused signal into an uplink WIFI high-frequency signal and an uplink WIFI low-frequency signal, transmit the uplink WIFI low-frequency signal to the first antenna for transmission, and when the current operating state of the second antenna is the transmission state and the antenna switching circuit is switched to the target antenna unit, transmit the uplink WIFI high-frequency signal to the target antenna unit for transmission via the antenna operating state switching circuit and the antenna switching circuit; The second multiplexing unit is further configured to, when the current operating state of the second antenna is the receiving state and the antenna switching circuit is switched to the target antenna unit, fuse the downlink WIFI high-frequency signal from the target antenna unit and transmitted through the antenna switching circuit and the antenna operating state switching circuit, and the downlink fusion signal from the first antenna into the downlink radio frequency fusion signal and transmit it to the signal separation circuit.

5. The radio frequency signal processing circuit as described in claim 2, characterized in that, The antenna operating state switching circuit includes a first switching control circuit and a first switching circuit. The first switching control circuit is electrically connected between the signal separation circuit and the first switching circuit, and the signal processing circuit, the first switching circuit and the antenna switching circuit are electrically connected in sequence. The first switching control circuit is used to generate a first radio frequency control signal based on the antenna operating state switching signal, and to control the first switching circuit to switch the current operating state of the second antenna through the first radio frequency control signal.

6. The radio frequency signal processing circuit as described in claim 5, characterized in that, The first switching control circuit includes a third multiplexing unit, a first detection circuit, a first comparator, a second detection circuit, and a second comparator; the single-ended side of the third multiplexing unit is electrically connected to the signal separation circuit, and the multi-ended side is electrically connected to the first detection circuit and the second detection circuit, respectively; the input terminal of the first comparator is electrically connected to the first detection circuit, and the output terminal is electrically connected to the first switching circuit; the input terminal of the second comparator is electrically connected to the second detection circuit, and the output terminal is electrically connected to the first switching circuit. The third multiplexing unit is used to separate the antenna operating state switching signal into a first radio frequency signal and a second radio frequency signal. The first detection circuit is used to process the first radio frequency signal into a first DC voltage signal; The second detection circuit is used to process the second radio frequency signal into a second DC voltage signal; The first comparator is used to compare the first DC voltage signal with a reference voltage and output a transmit switch signal based on the comparison result; The second comparator is used to compare the second DC voltage signal with a reference voltage and output a receive switch signal based on the comparison result; The first radio frequency control signal includes the transmit switch signal and the receive switch signal.

7. The radio frequency signal processing circuit as described in claim 6, characterized in that, The first switching circuit includes a single-pole double-throw switch and an RF front-end unit. The input terminal of the single-pole double-throw switch is electrically connected to the output terminal of the signal processing circuit and the first comparator, respectively, and both output terminals are electrically connected to the RF front-end unit. The RF front-end unit is electrically connected to the antenna switching circuit, the output terminal of the first comparator, and the output terminal of the second comparator, respectively. When the transmit switch signal is high and the receive switch signal is low, the single-pole double-throw switch switches to the transmit output point and the radio frequency front-end unit switches to the transmit state, so as to switch the current working state of the second antenna to the transmit state. When the transmit switch signal is low and the receive switch signal is high, the single-pole double-throw switch switches to the receive output point and the radio frequency front-end unit switches to the receive state, so as to switch the current working state of the second antenna to the receive state.

8. The radio frequency signal processing circuit as described in claim 2, characterized in that, The antenna switching circuit includes a second switching control circuit and a second switching circuit. The second switching control circuit is electrically connected between the signal separation circuit and the second switching circuit. The second switching circuit is electrically connected to the antenna operating state switching circuit, and the second switching circuit is electrically connected to each antenna element in the second antenna. The second switching control circuit is used to generate a second radio frequency control signal based on the antenna switching signal, and to control the second switching circuit to switch to the target antenna unit that is suitable for the current communication conditions through the second radio frequency control signal.

9. The radio frequency signal processing circuit as described in claim 8, characterized in that, The second switching control circuit includes a signal processing unit and a single-pole four-way switch. The input terminals of the single-pole four-way switch are electrically connected to the signal processing unit and the antenna working state switching circuit, respectively, and the four output terminals are electrically connected to one of the antenna elements of the second antenna. The signal processing unit is used to process the antenna switching signal into the second radio frequency control signal according to the signal strength between each second antenna and the external communication device; The single-pole four-way switch is used to switch to the output point electrically connected to the target antenna unit with the strongest signal strength of the external communication device under the action of the second radio frequency control signal.

10. An antenna, characterized in that, The antenna includes the radio frequency signal processing circuit and antenna module according to any one of claims 1-9, and the antenna module includes a first antenna and a second antenna; The first antenna is used to transmit uplink low-frequency WIFI signals and receive RTK signals and downlink low-frequency WIFI signals; The second antenna includes multiple antenna elements, which are used to transmit uplink WIFI high-frequency signals and receive downlink WIFI high-frequency signals under the switching control of the radio frequency signal processing circuit.

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