SOS double-antenna switching circuit and vehicle-mounted device

Abstract

The utility model relates to an SOS double-antenna switching circuit and a vehicle-mounted device, and relates to the technical field of electronics, and the SOS double-antenna switching circuit comprises an external antenna, a built-in standby antenna, a detection circuit, a change-over switch, a microcontroller and a main antenna; the detection circuit is electrically connected with the external antenna and the microcontroller respectively; the change-over switch is electrically connected with the microcontroller, the detection circuit and the main antenna respectively; in a first state, the change-over switch is electrically connected with the external antenna and is disconnected with the internal standby antenna; and in the second state, the change-over switch is electrically connected with the built-in standby antenna and is disconnected from the external antenna. Therefore, the connection state of the external antenna can be monitored in real time, and when the external antenna is disconnected, the connection is switched to the internal standby antenna in time, so that the situation that a signal cannot be received due to the fault of the external antenna is reduced.

Description

Technical Field

[0001] The present disclosure relates to the field of electronic technology, and in particular to an SOS dual-antenna switching circuit and a vehicle-mounted device. Background Art

[0002] Most existing SOS antennas or SOS vehicle-mounted devices use a single SOS (Morse Code distress signal) external antenna. The advantages of the SOS external antenna are strong anti-interference ability and strong receiving performance. The disadvantage is that the antenna may be abnormal after a failure and the SOS cannot be transmitted. When the existing SOS antenna is in use, it is impossible to switch to the SOS backup antenna, or the switching is complicated, resulting in signal reception delay. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides an SOS dual-antenna switching circuit and a vehicle-mounted device, which are used to receive SOS signals through the built-in antenna when the external antenna fails. The switching process is simple and fast, and the signal delay can be reduced.

[0004] The present disclosure provides an SOS dual-antenna switching circuit, comprising: an external antenna, a built-in backup antenna, a detection circuit, a switching switch, a microcontroller, and a main antenna;

[0005] The detection circuit is electrically connected to the external antenna and the microcontroller respectively;

[0006] The switching switch is electrically connected to the microcontroller, the detection circuit and the main antenna respectively;

[0007] In the first state, the switch is electrically connected to the external antenna and disconnected from the internal backup antenna;

[0008] In the second state, the switch is electrically connected to the built-in backup antenna and disconnected from the external antenna.

[0009] Optionally, the SOS dual-antenna switching circuit also includes a power supply circuit, which includes a first resistor, a first diode, and a first inductor, one end of the first resistor is connected to a first power supply voltage end, the other end of the first resistor is connected to one end of the first diode, the other end of the first diode is connected to one end of the first inductor, and the other end of the first inductor is connected to the external antenna.

[0010] Optionally, the detection circuit includes a detection port, a first capacitor, and a second resistor, the detection port is connected to the first capacitor and the second resistor, the other end of the first capacitor is grounded, and the other end of the second resistor is connected to the first resistor and the first diode.

[0011] Optionally, the switching switch includes a switching chip, pin 1 of the switching chip is connected to an external antenna, pin 2 of the switching chip is grounded, pin 3 of the switching chip is connected to a built-in backup antenna, pin 4 of the switching chip is connected to a power supply voltage VCC, pin 5 of the switching chip is connected to a second capacitor, the other end of the second capacitor is connected to the main antenna, pin 6 of the switching chip is connected to a third resistor and a fourth resistor, the other end of the third resistor is connected to a microcontroller, and the other end of the fourth resistor is grounded.

[0012] Optionally, between pin No. 1 of the external antenna and pin No. 1 of the switch, there are also: a second diode and a third capacitor;

[0013] One end of the second diode is connected to pin No. 1 of the external antenna, the third capacitor, and the first inductor, the other end of the second diode is grounded, and the other end of the third capacitor is connected to pin No. 1 of the switch.

[0014] Optionally, one end of the second inductor is connected to pin No. 1 of the built-in backup antenna and the third inductor, and the other end of the second inductor is connected to pin No. 3 of the switch;

[0015] The other end of the third inductor is connected to the fourth capacitor; the other end of the fourth capacitor is connected to the main antenna.

[0016] Optionally, pin 1 of the external antenna is connected to the switch, and other pins of the external antenna are grounded.

[0017] Optionally, pin 1 of the built-in backup antenna is connected to a switch, pin 2 of the built-in backup antenna is grounded, and other pins of the built-in backup antenna are reserved.

[0018] In a second aspect, the present disclosure provides a vehicle-mounted device, comprising the SOS dual-antenna switching circuit as described in the first aspect.

[0019] Compared with the prior art, the technical solution provided by the embodiments of the present disclosure has the following advantages: the detection circuit can detect the connection status of the external antenna in real time, and the switching switch can switch the built-in backup antenna when the external antenna fails, and the switching method is simple and fast. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

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

[0022] Figure 1 This is a schematic diagram of the connection of the SOS dual-antenna switching circuit according to an embodiment of the present disclosure;

[0023] Figure 2 This is a wiring diagram of the SOS dual antenna switching circuit described in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0024] In order to more clearly understand the above-mentioned objectives, features and advantages of the present disclosure, the scheme of the present disclosure will be further described below. It should be noted that the embodiments of the present disclosure and the features in the embodiments can be combined with each other without conflict.

[0025] In the following description, many specific details are set forth to facilitate a full understanding of the present disclosure, but the present disclosure may also be implemented in other ways different from those described herein; it is obvious that the embodiments in the specification are only part of the embodiments of the present disclosure, rather than all of the embodiments.

[0026] Figure 1 Please refer to the SOS dual antenna switching circuit connection diagram described in the embodiment of the present disclosure. Figure 1 In a first aspect, the present disclosure provides an SOS dual-antenna switching circuit 100, including: an external antenna 01, a built-in backup antenna 02, a detection circuit 03, a switching switch 04, a microcontroller 05, and a main antenna 06;

[0027] The detection circuit 03 is electrically connected to the external antenna 01 and the microcontroller 05 respectively; optionally, the detection circuit 03 uses an ADC (Analog-to-Digital Converter) for detection, which can convert the analog voltage signal into a digital signal for processing by a single chip microcomputer or other digital devices;

[0028] The switch 04 is electrically connected to the microcontroller 05, the detection circuit 03 and the main antenna 06 respectively; optionally, the switch 04 adopts an SP2T radio frequency switch;

[0029] In the first state, the switch 04 is electrically connected to the external antenna 01 and disconnected from the internal backup antenna 02;

[0030] In the second state, the switch 04 is electrically connected to the internal backup antenna 02 and disconnected from the external antenna 01 .

[0031] Specifically, the SOS dual-antenna switching circuit 100 includes an external antenna 01, which is electrically connected to a detection circuit 03. Optionally, the external antenna 01 is a dedicated shark fin antenna, which is electrically connected to a switching switch 04 under normal circumstances (in the first state) to receive an SOS signal; the SOS dual-antenna switching circuit 100 also includes a built-in backup antenna 02, which is electrically connected to the switching switch 04 in the second state, and the built-in backup antenna 02 is used to receive an SOS signal when the external antenna 01 is disconnected due to a fault or other reasons; the SOS dual-antenna switching circuit 100 also includes a detection circuit 03, which is electrically connected to the external antenna 01 and the microcontroller 05 respectively, and the detection circuit 03 is used to detect the connection status of the external antenna 01, and transmit the connection status information of the external antenna 01 to the microcontroller 05 in a timely manner; the SOS dual-antenna switching circuit 100 The SOS dual-antenna switching circuit 100 also includes a switching switch 04, which is electrically connected to the microcontroller 05, the detection circuit 03 and the main antenna 06 respectively. The switching switch 04 is used to disconnect the connection of the built-in backup antenna 02 when the external antenna 01 is connected, or the switching switch 04 is used to switch to connect the built-in backup antenna 02 when the external antenna 01 is disconnected; the SOS dual-antenna switching circuit 100 also includes a microcontroller 05, which is electrically connected to the switching switch 04 and the detection circuit 03 respectively, and the microcontroller 05 is used to receive the detection signal of the detection circuit 03, and then issue a switching instruction to the switching switch 04 according to the detection signal; the SOS dual-antenna switching circuit 100 also includes a main antenna 06, which is electrically connected to the switching switch 04. Regardless of whether the switching switch 04 is connected to the external antenna 01 or the built-in backup antenna 02, the switching switch 04 can transmit the received SOS signal to the main antenna 06.

[0032] In the first state, the external antenna 01 is connected normally, the switching switch 04 is disconnected from the built-in backup antenna 02, the switching switch 04 is electrically connected to the external antenna 01 and transmits the SOS signal received through the external antenna 01 to the main antenna 06; in the second state, the external antenna 01 is disconnected, the switching switch 04 is switched to the built-in backup antenna 02, is electrically connected to the built-in backup antenna 02 and transmits the SOS signal received through the built-in backup antenna 02 to the main antenna 06; in this way, through the real-time detection of the external antenna 01 by the detection circuit 03, the switching switch 04 can be used to switch to the built-in backup antenna 02 in time when the external antenna 01 is disconnected, thereby reducing the impact on the reception of the SOS signal.

[0033] Figure 2 For the SOS dual antenna switching circuit wiring diagram described in the embodiment of the present disclosure, please refer to Figure 1 and Figure 2The present disclosure provides an SOS dual-antenna switching circuit 100, which further includes a power supply circuit 07, which is used to supply power to an external antenna J1707. The power supply circuit 07 includes a first resistor R1701, a first diode D1701, and a first inductor L1701, wherein a first end of the first resistor R1701 is connected to a first power supply voltage terminal SLEEP DOWN, and a voltage of the first power supply voltage terminal SLEEP DOWN is 3.3V, a second end of the first resistor R1701 is connected to a second resistor R1703 and a first diode D1701, and the other end of the first diode D1701 is connected to the first inductor L1701, and the other end of the first inductor L1701 is connected to pin 1 of the external antenna J1707, a second diode D1702, and a third capacitor C1754; in this way, the power supply circuit 07 with a specific structure can supply power to the external antenna J1707.

[0034] Optionally, capacitor C1702 and capacitor C1704 may be connected between the first diode D1701 and the first resistor R1701, one end of capacitor C1704 is connected to the first diode D1701 and capacitor C1704, the other end of capacitor C1704 is grounded, one end of capacitor C1702 is connected to capacitor C1704, the first resistor R1701, and the second resistor R1703, the other end of capacitor C1702 is grounded; an artificial detection point TP1701 may also be set between capacitor C1702 and the first resistor R1701 for internal test detection of the connection status of the external antenna J1707.

[0035] Please continue to refer to Figure 1 and Figure 2 The present disclosure provides an SOS dual antenna switching circuit 100, wherein the detection circuit 03 includes a detection port MAIN-ANT-ADC, a first capacitor C1705, and a second resistor R1703, wherein the detection port MAIN-ANT-ADC is connected to the first capacitor C1705 and the second resistor R1703, the other end of the first capacitor C1705 is grounded, and the other end of the second resistor R1703 is connected to the first resistor R1701 and the capacitor C1702; thus, by setting a detection circuit 03 with a specific structure, the connection status of the external antenna J1707 can be detected in real time.

[0036] It should be noted that the first resistor R1701 connected in series on the power supply circuit 07 of the external antenna J1707 is a 10K resistor, and the second resistor R1703 connected to the detection port MAIN-ANT-ADC is also a 10K resistor; when the external antenna J1707 is connected normally, the detection voltage of the detection port MAIN-ANT-ADC is approximately half of the voltage 3.3V provided by the first voltage terminal SLEEP DOWN, that is, the detection voltage of the detection port MAIN-ANT-ADC is about 1.67V; when the external antenna J1707 fails or has poor contact, the detection voltage of the detection port MAIN-ANT-ADC is approximately equal to the voltage 3.3V provided by the first voltage terminal SLEEP DOWN, that is, the detection voltage of the detection port MAIN-ANT-ADC increases to 3.3V, and the switching switch 04 is switched to connect the built-in backup antenna ANT1700, so that the main antenna 06 always maintains a signal receiving state.

[0037] Please continue to refer to Figure 1 and Figure 2 The present disclosure provides an SOS dual antenna switching circuit 100, wherein the switching switch 04 includes a switching chip U1700, model QX8712G, and the switching chip U1700 includes 6 pins, wherein pin 1 of the switching chip U1700 is connected to pin 1 of the external antenna J1707, pin 2 of the switching chip U1700 is grounded, pin 3 of the switching chip U1700 is connected to pin 1 of the built-in backup antenna ANT1700, pin 4 of the switching chip U1700 is connected to a power supply voltage VCC, and the power supply voltage VCC is 3.8V, pin 5 of the switching chip U1700 is connected to a second capacitor C1706, and the other end of the second capacitor C1706 is connected to the main antenna ANT-MAIN, pin 6 of the switching chip U1700 is connected to a third resistor R1731 and a fourth resistor R1732, and the other end of the third resistor R1731 is connected to the microcontroller MAIN ANT CTRL, the other end of the fourth resistor R1732 is grounded; in this way, through the specifically connected switching chip U1700, the control signal from the microcontroller MAIN ANT CTRL can be received, and the external antenna J1707 and the built-in backup antenna ANT1700 can be switched in time to reduce the influence of the main antenna 06 on signal reception.

[0038] It should be noted that the detection port MAIN-ANT-ADC determines the connection status of the external antenna J1707 through the detected detection voltage and feeds back to the microcontroller MAIN ANT CTRL. The microcontroller MAIN ANT CTRL controls the switching of the switching switch 04 through the logic circuit. For example, when the microcontroller MAIN ANT CTRL inputs a high level to the switching chip U1700, pin 1 RF2 of the switching chip U1700 is connected to the external antenna J1707, and pin 3 RF1 of the switching chip U1700 is disconnected from the built-in backup antenna ANT1700. At this time, the switching switch 04 is connected to the external antenna J1707; when the microcontroller MAIN ANTCTRL inputs a low level to the switching chip U1700, pin 1 RF2 of the switching chip U1700 is disconnected from the external antenna J1707, and pin 3 RF1 of the switching chip U1700 is connected to the built-in backup antenna ANT1700. At this time, the switching switch 04 is connected to the built-in backup antenna ANT1700.

[0039] In an optional embodiment provided by the present disclosure, when the voltage detected by the detection port MAIN-ANT-ADC is 1.67V, it indicates that the external antenna J1707 is connected normally, the microcontroller MAIN ANT CTRL inputs a high level to the switching chip U1700, and the switching switch 04 is turned on with the external antenna J1707; when the voltage detected by the detection port MAIN-ANT-ADC is 3.3V, it indicates that the external antenna J1707 is disconnected, the microcontroller MAIN ANT CTRL inputs a low level to the switching chip U1700, and the switching switch 04 is turned on with the built-in backup antenna ANT1700; this is only an example, and does not represent the actual control method of the microcontroller MAIN ANT CTRL over the switching switch 04, nor does it represent the actual output method of the logic circuit.

[0040] Please continue to refer to Figure 1 and Figure 2 The present disclosure provides an SOS dual antenna switching circuit 100, and further includes: a second diode D1702 and a third capacitor C1754 between pin 1 of the external antenna J1707 and pin 1 of the switching switch 04; wherein one end of the second diode D1702 is connected to pin 1 of the external antenna J1707, the third capacitor C1754, and the first inductor L1701, the other end of the second diode D1702 is grounded, and the other end of the third capacitor C1754 is connected to pin 1 of the switching chip U1700.

[0041] Optionally, a capacitor C1755 is also included between the second diode D1702 and the third capacitor C1754, one end of the capacitor C1755 is respectively connected to the second diode D1702 and the third capacitor C1754, and the other end of the capacitor C1755 is grounded; optionally, a capacitor C1725 is also included between pin No. 1 of the switching chip U1700 and the third capacitor C1754, one end of the capacitor C1725 is respectively connected to the switching chip U1700 and the third capacitor C1754, and the other end of the capacitor C1725 is grounded.

[0042] Please continue to refer to Figure 1 and Figure 2 The present disclosure provides an SOS dual-antenna switching circuit 100, wherein a second inductor L1705 is connected between pin No. 1 of a built-in backup antenna ANT1700 and pin No. 3 of a switching chip U1700, one end of the second inductor L1705 is electrically connected to the built-in backup antenna ANT1700 and a third inductor L1708, the other end of the second inductor L1705 is electrically connected to pin No. 3 of the switching chip U1700, the other end of the third inductor L1708 is connected to a fourth capacitor C1770, and the other end of the fourth capacitor C1770 is connected to the main antenna ANT-MAIN.

[0043] Optionally, a capacitor C1761 is also included between pin No. 1 of the built-in backup antenna ANT1700 and the second inductor L1705, one end of the capacitor C1761 is connected to the built-in backup antenna ANT1700, the second inductor L1705, and the third inductor L1708, and the other end of the capacitor C1761 is grounded; optionally, a capacitor C1702 is also included between the third inductor L1708 and the fourth capacitor C1770, one end of the capacitor C1702 is connected to the third inductor L1708 and the fourth capacitor C1770, and the other end of the capacitor C1702 is grounded.

[0044] Please continue to refer to Figure 1 and Figure 2 The present disclosure provides an SOS dual antenna switching circuit 100, wherein the external antenna J1707 includes a plurality of pins, wherein pin No. 1 of the external antenna J1707 is connected to pin No. 1 of the switching chip U1700, and the other pins of the external antenna J1707 are grounded.

[0045] Please continue to refer to Figure 1 and Figure 2 The present disclosure provides an SOS dual-antenna switching circuit 100, wherein the built-in backup antenna ANT1700 includes multiple pins, wherein pin 1 of the built-in backup antenna ANT1700 is connected to pin 3 of the switching chip U1700, pin 2 of the built-in backup antenna ANT1700 is grounded, and the other pins of the built-in backup antenna ANT1700 are standby.

[0046] In the second aspect, an embodiment of the present disclosure provides a vehicle-mounted device, which includes the SOS dual-antenna switching circuit 100 as described in the first aspect. The present disclosure does not specifically limit the appearance of the vehicle-mounted device, but only requires that the SOS dual-antenna switching circuit 100 is located inside the vehicle-mounted device and can receive SOS signals for the corresponding vehicle.

[0047] In summary, the present invention provides an SOS dual-antenna switching circuit and a vehicle-mounted device, including: an external antenna, a built-in backup antenna, a detection circuit, a switching switch, a microcontroller, and a main antenna; the external antenna and the built-in backup antenna are switched by the switching switch, and when the external antenna fails, the connection can be switched to the built-in backup antenna to ensure the reception of the SOS signal; by connecting the detection circuit to the external antenna, the connection status of the external antenna can be detected in real time; the switching switch is electrically connected to the microcontroller, the detection circuit and the main antenna respectively, and the microcontroller can issue response instructions according to different detection results to control the switching of the switching switch; the main antenna is connected to the switching switch, and no matter whether the switching switch is connected to the external antenna or the built-in backup antenna, the received SOS signal can be transmitted to the main antenna.

[0048] It should be noted that, in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0049] The above description is only a specific embodiment of the present disclosure, so that those skilled in the art can understand or implement the present disclosure. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present disclosure. Therefore, the present disclosure will not be limited to the embodiments described herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An SOS dual-antenna switching circuit, characterized in that: include: External antenna, internal backup antenna, detection circuit, switching switch, microcontroller, main antenna; The detection circuit is electrically connected to the external antenna and the microcontroller respectively; The switching switch is electrically connected to the microcontroller, the detection circuit and the main antenna respectively; In the first state, the switch is electrically connected to the external antenna and disconnected from the internal backup antenna; In the second state, the switch is electrically connected to the built-in backup antenna and disconnected from the external antenna.

2. The SOS dual antenna switching circuit according to claim 1, characterized in that: The SOS dual-antenna switching circuit also includes a power supply circuit, which includes a first resistor, a first diode, and a first inductor. One end of the first resistor is connected to a first power supply voltage end, the other end of the first resistor is connected to one end of the first diode, the other end of the first diode is connected to one end of the first inductor, and the other end of the first inductor is connected to the external antenna.

3. The SOS dual antenna switching circuit according to claim 1, characterized in that: The detection circuit includes a detection port, a first capacitor, and a second resistor. The detection port is connected to the first capacitor and the second resistor. The other end of the first capacitor is grounded, and the other end of the second resistor is connected to the first resistor and the first diode.

4. The SOS dual antenna switching circuit according to claim 1, characterized in that: The switching switch includes a switching chip, pin 1 of the switching chip is connected to an external antenna, pin 2 of the switching chip is grounded, pin 3 of the switching chip is connected to a built-in backup antenna, pin 4 of the switching chip is connected to a power supply voltage VCC, pin 5 of the switching chip is connected to a second capacitor, the other end of the second capacitor is connected to a main antenna, pin 6 of the switching chip is connected to a third resistor and a fourth resistor, the other end of the third resistor is connected to a microcontroller, and the other end of the fourth resistor is grounded.

5. The SOS dual antenna switching circuit according to claim 4, characterized in that: Also included between pin No. 1 of the external antenna and pin No. 1 of the switch are: a second diode and a third capacitor; One end of the second diode is connected to pin No. 1 of the external antenna, the third capacitor, and the first inductor, the other end of the second diode is grounded, and the other end of the third capacitor is connected to pin No. 1 of the switch.

6. The SOS dual antenna switching circuit according to claim 4, characterized in that: One end of the second inductor is connected to pin 1 of the built-in backup antenna and the third inductor, and the other end of the second inductor is connected to pin 3 of the switch; The other end of the third inductor is connected to the fourth capacitor; the other end of the fourth capacitor is connected to the main antenna.

7. The SOS dual antenna switching circuit according to claim 1, characterized in that: Pin 1 of the external antenna is connected to the switch, and the other pins of the external antenna are grounded.

8. The SOS dual antenna switching circuit according to claim 1, characterized in that: Pin 1 of the built-in backup antenna is connected to the switch, pin 2 of the built-in backup antenna is grounded, and other pins of the built-in backup antenna are reserved.

9. A vehicle-mounted device, comprising the SOS dual-antenna switching circuit according to any one of claims 1 to 8.

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