Internal and external antenna automatic switching device and wireless network equipment

Abstract

The utility model provides an internal and external antenna automatic switching device and wireless network equipment. The device comprises a radio frequency switching module, a first detection unit, a built-in antenna and a radio frequency connecting seat used for being connected with an external antenna, a first radio frequency pin of the radio frequency switching module is connected with the first end of the radio frequency connecting seat, a second radio frequency pin of the radio frequency switching module is connected with the built-in antenna, and a control pin of the radio frequency switching module is connected with the first detection unit so as to receive a first detection signal sent by the first detection unit; the first detection unit is connected with the first end of the radio frequency connecting seat through the detection node so as to detect whether the external antenna is connected with the radio frequency connecting seat; the second end of the radio frequency connecting seat is grounded. The device of the scheme is simple in overall structure, convenient to use and high in internal and external antenna switching speed.

Description

Technical Field

[0001] The present application relates to the field of wireless communication technology, and in particular to an automatic switching device for internal and external antennas and wireless network equipment. Background Art

[0002] The world has now entered a period of rapid development of the Internet of Things. Wireless network devices can be found everywhere and have permeated our lives. From small Bluetooth headsets to large cars, these wireless network devices have brought great convenience to people's lives.

[0003] In the related art, wireless network devices usually rely on their internal built-in antennas to connect to the network. However, the application scenarios of wireless network devices are complex and changeable. Under some closed conditions, wireless network devices with only built-in antennas may face the problem of poor signal or even no signal, which seriously affects user use.

[0004] In view of this, this application is hereby filed. Utility Model Content

[0005] The present application is proposed in view of the above problems. According to one aspect of the present application, a device for automatic switching between internal and external antennas is provided, comprising: a radio frequency switching module, a first detection unit, a built-in antenna and a radio frequency connector for connecting an external antenna; a first radio frequency pin of the radio frequency switching module is connected to a first end of the radio frequency connector, a second radio frequency pin of the radio frequency switching module is connected to the built-in antenna, and a control pin of the radio frequency switching module is connected to the first detection unit to receive a first detection signal emitted by the first detection unit; the first detection unit is connected to the first end of the radio frequency connector via a detection node to detect whether the external antenna is connected to the radio frequency connector; the second end of the radio frequency connector is grounded; wherein, when the external antenna is connected to the radio frequency connector, the first detection signal emitted by the first detection unit is a valid signal; wherein, at least when the first detection signal is a valid signal, the radio frequency communication pin of the radio frequency switching module is connected to the first radio frequency pin, otherwise, the radio frequency communication pin of the radio frequency switching module is connected to the second radio frequency pin.

[0006] Exemplarily, a second detection unit is also included, which is connected to the RF connection socket via the detection node to detect whether the external antenna is short-circuited; the control pin of the RF switching module is connected to the second detection unit to receive a second detection signal emitted by the second detection unit; wherein, when the first detection signal is a valid signal and the second detection signal is a non-short-circuit signal, the RF communication pin of the RF switching module is connected to the first RF pin, otherwise, the RF communication pin of the RF switching module is connected to the second RF pin.

[0007] Exemplarily, the second detection unit includes a first resistor module, a second resistor module, and a first detection module; a first end of the first resistor module is connected to a first power supply, and a second end of the first resistor module is connected to the detection node; a first end of the second resistor module is connected to the second end of the first resistor module, and a second end of the second resistor module is grounded; a control end of the first detection module is connected to the second end of the first resistor module, a first end of the first detection module is connected to a second power supply via a first sampling node, a second end of the first detection module is grounded, and the first sampling node is connected to a control pin of the RF switching module; wherein, when the external antenna is short-circuited, the voltage of the first sampling node does not satisfy the conduction condition of the first detection module, and a first end and a second end of the first detection module are in a non-conducted state, and a second detection signal output by the first sampling node is a short-circuit signal; when the external antenna is not short-circuited, the voltage of the first sampling node satisfies the conduction condition of the first detection module, and a first end and a second end of the first detection module are in a conducted state, and a second detection signal output by the first sampling node is a non-short-circuit signal.

[0008] Exemplarily, the second detection unit further includes a third resistor module, and the third resistor module is connected in series between the second power supply and the first sampling node.

[0009] Exemplarily, the first detection module is an N-channel metal oxide semiconductor field effect transistor.

[0010] Exemplarily, the second detection unit further includes an inductor module, and the inductor module is connected in series between the first resistor module and the detection node.

[0011] Exemplarily, the device further includes a first diode and a second diode, the first diode is connected in series between the first detection unit and the control pin of the RF switching module, and the second diode is connected in series between the second detection unit and the control pin of the RF switching module.

[0012] Exemplarily, the first detection unit includes a fourth resistor module, a fifth resistor module, a sixth resistor module, and a second detection module; a first end of the fourth resistor module is connected to a third power supply, and a second end of the fourth resistor module is connected to the detection node; a first end of the fifth resistor module is connected to the second end of the fourth resistor module, and a second end of the fifth resistor module is grounded; a control end of the second detection module is connected to the second end of the fourth resistor module, a first end of the second detection module is connected to a fourth power supply, a second end of the second detection module is connected to a first end of the sixth resistor module via a second sampling node, and a second end of the sixth resistor module is grounded; the second sampling node is connected to a control pin of the RF switching module; wherein, when the external antenna is connected to the RF connector, the voltage of the second sampling node does not satisfy the conduction condition of the second detection module, the first end and the second end of the second detection module are in a non-conducted state, and a first detection signal output by the second sampling node is a valid signal; when the external antenna is not connected to the RF connector, the voltage of the second sampling node satisfies the conduction condition of the second detection module, the first end and the second end of the second detection module are in a conducted state, and a first detection signal output by the second sampling node is an invalid signal.

[0013] Exemplarily, the second detection module is an N-channel metal oxide semiconductor field effect transistor.

[0014] According to another aspect of the present application, there is provided a wireless network device including the above-mentioned internal and external antenna automatic switching device.

[0015] In the above technical solution, the RF switching module is connected to both the RF connector and the internal antenna at the same time, and the RF switching module can switch between the internal antenna and the external antenna at least according to the detection result of the first detection module (i.e., the first detection signal). Thus, the user can choose to insert the external antenna into the RF connector according to the need to communicate using the external antenna. The overall structure of the device in this solution is simple, easy to use, and has a fast switching speed between the internal and external antennas. Moreover, this solution can use the external antenna to receive signals in an environment with poor or no signal to ensure the signal strength, which helps to improve the user experience.

[0016] The above description is only an overview of the technical solution of the present application. In order to be able to understand the technical means of the present application more clearly, it can be implemented according to the content of the specification. And in order to make the above and other purposes, features, and advantages of the present application more obvious and understandable, the following specifically enumerates the specific embodiments of the present application. Description of the Drawings

[0017] Upon reading the following detailed description of the preferred embodiments, various other advantages and benefits will become apparent to those of ordinary skill in the art. The drawings are only for the purpose of illustrating the preferred embodiments and are not considered to be a limitation of the present application. Also, throughout the drawings, the same reference numerals are used to represent the same components. In the drawings:

[0018] Figure 1 Shows a schematic block diagram of an internal and external antenna automatic switching device according to an embodiment of the present application;

[0019] Figure 2 Shows a schematic circuit diagram of an internal and external antenna automatic switching device according to an embodiment of the present application;

[0020] Figure 3 Shows a schematic circuit diagram of a second detection unit according to an embodiment of the present application;

[0021] Figure 4 Shows a schematic circuit diagram of a first detection unit according to an embodiment of the present application.

[0022] Figure 1 Among them: 1. RF switching module; 101. RF communication pin; 102. Second RF pin; 103. First RF pin; 104. Control pin; 2. First detection unit; 3. RF connector; 4. Internal antenna; 5. Second detection unit. Detailed Embodiments

[0023] In the following description, a large number of details are provided to enable a thorough understanding of the present invention. However, those skilled in the art can understand that the following description only relates to the preferred embodiments of the present invention, and the present invention can be implemented without one or more of such details. In addition, to avoid confusion with the present invention, some well-known technical features in the art are not described.

[0024] According to one aspect of an embodiment of the present application, an internal and external antenna automatic switching device is provided. Figure 1 Shows a schematic block diagram of an internal and external antenna automatic switching device according to an embodiment of the present application, as Figure 1 shown, the device includes: an RF switching module 1, a first detection unit 2, an internal antenna 4, and an RF connector 3 for connecting an external antenna. The first RF pin 103 of the RF switching module 1 is connected to the first end of the RF connector 3, the second RF pin 102 of the RF switching module 1 is connected to the internal antenna 4, and the control pin 104 of the RF switching module 1 is connected to the first detection unit 2 to receive a first detection signal sent by the first detection unit 2; the first detection unit 2 is connected to the first end of the RF connector 3 via a detection node A to detect whether the external antenna is connected to the RF connector 3; the second end of the RF connector 3 is grounded.

[0025] In the solution as shown in Figure 1 When the external antenna is connected to the RF connector 3, the first detection signal sent by the first detection unit 2 is a valid signal; wherein, at least when the first detection signal is a valid signal, the RF communication pin 101 of the RF switching module 1 is conducted with the first RF pin 103, otherwise, the RF communication pin 101 of the RF switching module 1 is conducted with the second RF pin 102.

[0026] In this article, the RF connector 3 is used to connect the external antenna. In some embodiments, there is a jack on the RF connector 3 for inserting the external antenna, and when the external antenna is inserted into this jack, the external antenna is connected to the RF connector 3.

[0027] In this article, the first detection unit 2 is connected to the first end of the RF connector 3 via a detection node to detect whether the external antenna is connected to the RF connector 3, and the first detection unit 2 can send a first detection signal to the control pin 104 of the RF switching module 1. This first detection signal can be used to represent the insertion situation of the external antenna. When the first detection signal is an invalid signal indicating that the external antenna is not connected to the RF connector 3, it means that the external antenna is not connected to the RF connector 3, and at this time, the built-in antenna 4 can be used for networking. When the first detection signal is a valid signal indicating that the external antenna is connected to the RF connector 3, it means that the external antenna has been connected to the RF connector 3, and at this time, the external antenna can be used for networking. Of course, in some embodiments, when the external antenna has been connected to the RF connector 3, it can be determined whether this connection is a normal connection, that is, to determine whether the external antenna is short-circuited (for example, it can be detected by the second detection unit shown below), and when the external antenna is normally connected to the RF connector 3, then the external antenna is used for networking.

[0028] As described above, the first end of the RF connector 3 is connected to the first detection unit 2 via a detection node, and the second end of the RF connector 3 is grounded. It can be understood that when an external antenna is connected to the RF connector 3, the first end and the second end of the RF connector 3 are conducted, and at this time, it is equivalent to grounding the detection node. Based on this, in some embodiments, the first detection unit 2 can be used to output a first detection signal according to the voltage value at the detection node. For example, a power supply can be set to be connected to the detection node via a resistor. When the detection node is grounded (i.e., the external antenna is connected to the RF connector 3), the external antenna and the resistor divide the voltage, and the voltage at the detection node is less than the power supply voltage. When the external antenna is not connected to the RF connector 3, the first end and the second end of the RF connector 3 are in an open state (i.e., disconnected), and at this time, the voltage at the detection node is the voltage of the power supply connected thereto. In this case, the first detection unit 2 can be any existing or future-developed chip or circuit that can output different signals according to different voltages at the detection node, and the present application does not limit this. Of course, the first detection unit 2 can also be a relay circuit, an opto-isolation circuit, or a field-effect transistor circuit, and the present application does not limit this. For example, the first detection unit 2 can be composed of a relay circuit. In this embodiment, the first detection unit 2 includes a relay coil and a relay switch; one end of the relay coil is connected to the power supply, and the other end is connected to the detection node. One end of the relay switch is connected to the power supply, and the other end is grounded. And an output node is connected in series between the relay switch and the power supply, and the output node is connected to the control pin 104 of the RF switching module 1. In this case, the energization and de-energization of the relay coil can be used to control the relay switch to be opened or closed, so that different voltages exist at the output node, and this voltage is the first detection signal.

[0029] In this article, the RF switching module 1 has an RF communication pin 101, and this RF communication pin 101 is used for communication with other processors and / or controllers. Specifically, this RF communication pin 101 can be connected to the RF signal transceiver pin of the device that uses this device to connect to the network, for registering the network and sending / receiving data packets. In the Figure 1 embodiment shown, an RF signal line is connected to the RF communication pin 101 of the RF switching module 1, and the end of the RF signal line far from the RF switching module 1 is used to connect to a processor and / or controller. When the RF communication pin 101 of the RF switching module 1 is conducted with the first RF pin 103, the processor and / or controller connected to the RF communication pin 101 can communicate with the network via the external antenna. When the RF communication pin 101 of the RF switching module 1 is conducted with the second RF pin 102, the processor and / or controller connected to the RF communication pin 101 can communicate with the network via the internal antenna 4.

[0030] Figure 2 Shows a circuit schematic diagram of an internal and external antenna automatic switching device according to an embodiment of the present application. AsFigure 2 As shown, the radio frequency switching module U1 has a first radio frequency pin RF1, a second radio frequency pin RF2, a power supply pin VCC, a radio frequency communication pin RFC, a control pin VCTL, and a ground pin GND, where the ground pin GND is grounded and the power supply pin VCC is connected to the power supply ANT_POWER 5. The first radio frequency pin RF1 is connected to the first end of the radio frequency connector CON1, the second radio frequency pin RF2 is connected to the built-in antenna ANT1, and the control pin VCTL is connected to the first detection unit to receive the first detection signal GPS_ACTIVE _ANT _DET sent by the first detection unit; the first detection unit is connected to the first end of the radio frequency connector CON1 via the detection node A (in this embodiment, the detection node A is connected to the first detection unit through EXT_ANT) to detect whether the external antenna is connected to the radio frequency connector CON1; the second end of the radio frequency connector CON1 is grounded.

[0031] In Figure 2 In the shown embodiment, a capacitor C2, a capacitor C3, a capacitor C4, and a resistor R7 are also provided. Among them, the first end of the capacitor C2 is connected to the power supply ANT_POWER 5, and the second end is grounded. The capacitor C3 is connected in series between the first radio frequency pin RF1 and the first end of the radio frequency connector CON1. The first end of the capacitor C4 is connected to the control pin VCTL, and the second end is grounded. The first end of the resistor R7 is connected to the control pin VCTL, and the second end is grounded.

[0032] In the above technical solution, the radio frequency switching module is connected to both the radio frequency connector and the built-in antenna at the same time, and the radio frequency switching module can switch between the built-in antenna and the external antenna at least according to the detection result of the first detection module (i.e., the first detection signal). Thus, the user can choose to insert the external antenna into the radio frequency connector as needed to communicate using the external antenna. The overall structure of the device in this solution is simple, easy to use, and has a fast switching speed between the internal and external antennas. Moreover, this solution can use the external antenna to receive signals in an environment with poor or no signal to ensure the signal strength, which helps to improve the user experience.

[0033] Exemplarily, continuing to refer to Figure 1 , the device further includes a second detection unit 5. The second detection unit 5 is connected to the radio frequency connector 3 via the detection node A to detect whether the external antenna is short-circuited; the control pin 104 of the radio frequency switching module 1 is connected to the second detection unit 5 to receive the second detection signal sent by the second detection unit 5.

[0034] In the solution of this example, when the first detection signal is a valid signal and the second detection signal is a non-short-circuit signal, the radio frequency communication pin 101 of the radio frequency switching module 1 is conducted with the first radio frequency pin 103; otherwise, the radio frequency communication pin 101 of the radio frequency switching module 1 is conducted with the second radio frequency pin 102.

[0035] In this text, the external antenna is an active device. It can be understood that when the external antenna can work properly, the detection node located before the external antenna is grounded through the external antenna. When the external antenna is powered by the power supply, the voltage of the detection node is equal to the voltage divided by the external antenna. When the external antenna is short-circuited, the detection node located before the external antenna is equivalent to being directly grounded, and the voltage of the detection node is 0 at this time. Therefore, the second detection unit can determine whether the external antenna is short-circuited based on the voltage condition of the detection node. Optionally, the second detection unit can be any existing or future-developed chip or circuit that can output different second detection signals according to different voltages of the detection node, and this application does not limit this.

[0036] In the embodiment as Figure 2 shown, the second detection unit is connected to the first end of the RF connector CON1 via the detection node A (in this embodiment, the detection node A is connected to the second detection unit through EXT_ANT), and the second detection signal GPS _ANT_SHORT_DET sent by the second detection unit is received by the control pin VCTL.

[0037] In the solution of this example, the second detection signal sent by the second detection unit can be a short-circuit signal or a non-short-circuit signal. When the second detection signal is a short-circuit signal, it indicates that the external antenna is short-circuited. When the second detection signal is a non-short-circuit signal, it indicates that the external antenna is in a non-short-circuit state. As described above, when the first detection signal is a valid signal and the second detection signal is a non-short-circuit signal, the RF communication pin of the RF switching module is conducted with the first RF pin, otherwise, the RF communication pin of the RF switching module is conducted with the second RF pin. In other words, when the first detection signal is a valid signal and the second detection signal is a non-short-circuit signal, it indicates that the external antenna is connected to the RF connector and can work properly, and at this time, the external antenna can be switched for network communication. When the first detection signal is an invalid signal, it indicates that the external antenna is not connected to the RF connector, and at this time, the internal antenna can be used for network communication. When the second detection signal is a short-circuit signal, the external antenna cannot work properly at this time, so the internal antenna can be used for network communication.

[0038] The above technical solution can provide a relatively accurate basis for the switching between the internal and external antennas by setting the second detection unit for determining whether the external antenna is short-circuited, so as to better provide high-quality network services for users.

[0039] Exemplarily, the second detection unit includes a first resistor module, a second resistor module, and a first detection module; a first end of the first resistor module is connected to a first power supply, and a second end of the first resistor module is connected to a detection node; a first end of the second resistor module is connected to the second end of the first resistor module, and a second end of the second resistor module is grounded; a control end of the first detection module is connected to the second end of the first resistor module, a first end of the first detection module is connected to a second power supply via a first sampling node, a second end of the first detection module is grounded, and the first sampling node is connected to a control pin of the radio frequency switching module.

[0040] In the solution of this example, when the external antenna is short-circuited, the voltage of the first sampling node does not meet the conduction condition of the first detection module, and the first end and the second end of the first detection module are in a non-conducted state. The second detection signal output by the first sampling node is a short-circuit signal; when the external antenna is not short-circuited, the voltage of the first sampling node meets the conduction condition of the first detection module, and the first end and the second end of the first detection module are in a conducted state. The second detection signal output by the first sampling node is a non-short-circuit signal.

[0041] The first detection module can be selected according to actual needs as long as it can meet the above requirements. In some embodiments, the first detection module is an N-channel metal oxide semiconductor (NMOS) field effect transistor (which can be simply referred to as an NMOS transistor). In this embodiment, the voltage of the first sampling node meeting the conduction condition of the first detection module means that the voltage of the first sampling node is greater than or equal to the conduction threshold of the NMOS transistor. At this time, the voltage of the G pole of the NMOS transistor is greater than or equal to the conduction threshold, and the D pole and the S pole are conducted. The voltage of the first sampling node not meeting the conduction condition of the first detection module means that the voltage of the first sampling node is less than the conduction threshold of the NMOS transistor. At this time, the voltage of the G pole of the NMOS transistor is less than the conduction threshold, and the D pole and the S pole are cut off.

[0042] As described above, when the external antenna is short-circuited, the second detection signal output by the first sampling node is a short-circuit signal; when the external antenna is not short-circuited, the second detection signal output by the first sampling node is a non-short-circuit signal. It can be understood that when the external antenna is short-circuited, the first end and the second end of the first detection module are in a non-conducted state. At this time, the voltage of the first sampling node is a high level of 3.3V. When the external antenna is not short-circuited, the first end and the second end of the first detection module are in a conducted state. At this time, the voltage value of the first sampling node is a low level of 0V. In other words, in the solution of this embodiment, the short-circuit signal is a high-level signal, and the non-short-circuit signal is a low-level signal.

[0043] Figure 3 A circuit schematic diagram of the second detection unit according to an embodiment of the present application is shown. As Figure 3As shown, the second detection unit includes a first resistor module R1, a second resistor module R2, and a first detection module Q1, and the first detection module Q1 is an NMOS transistor. The first end of the first resistor module R1 is connected to the first power supply ANT_POWER1, and the second end of the first resistor module R1 is connected to the detection node A (in this embodiment, the second end of R1 is connected to the detection node A via EXT_ANT); the first end of the second resistor module R2 is connected to the second end of the first resistor module R1, and the second end of the second resistor module R2 is grounded; the control terminal G of the first detection module Q1 is connected to the second end of the first resistor module R1, the first end D of the first detection module Q1 is connected to the second power supply ANT_POWER2 via the first sampling node B, and the second end S of the first detection module Q1 is grounded. The first sampling node B is connected to the control pin of the RF switching module, and the second detection signal GPS _ANT_SHORT_DET is received by the control pin.

[0044] In Figure 3 In the embodiment shown, the second end of the first resistor module R1 is connected to the detection node A, so their voltages are equal. In this case, the voltage of the G pole of the first detection module Q1 is equal to the voltage of the detection node A. When the D pole and the S pole are cut off, the second detection signal GPS _ANT_SHORT_DET is at a high level, and when the D pole and the S pole are conducting, the second detection signal GPS _ANT_SHORT_DET is at a low level.

[0045] Optionally, the resistance value relationship between the first resistor module and the second resistor module satisfies the following condition: when the first resistor module and the second resistor module are in series, the voltage value divided by the second resistor module satisfies the conduction condition of the first detection module. Taking Figure 3 as an example for illustration, when the external antenna is not connected to the RF connector, the first end and the second end of the RF connector are cut off. At this time, the current flow direction of the second power supply ANT_POWER2 is along the first resistor module and the second resistor module. In this case, the voltage of the G pole of the first detection module Q1 is the voltage value divided by the second resistor module. In this embodiment, when the first resistor module and the second resistor module are in series, the voltage value divided by the second resistor module satisfies the conduction condition of the first detection module. That is, when the external antenna is not connected to the RF connector, the voltage of the G pole of the first detection module Q1 satisfies the conduction condition of the first detection module. At this time, the first sampling node B outputs a low level. Thus, it can be ensured that the second detection signal output by the first sampling node B when the external antenna is not connected to the RF connector is different from the second detection signal (high level) output by the first sampling node B when the external antenna is short-circuited, preventing the situation where the external antenna is not connected to the RF connector from being misjudged as an external antenna short circuit, which helps to provide a more accurate basis for the switching between the internal and external antennas. The present application does not limit the specific resistance values of the first resistor module and the second resistor module, as long as they satisfy the above relationship.

[0046] In a specific embodiment, the circuit structure shown in Figure 3 is used as the second detection module. In this embodiment, the power consumption of the external antenna is 9 mA @ 3.3 V, the resistance value of the first resistor module R1 is 20 Ω, the resistance value of the second resistor module R2 is 1 MΩ, the conduction threshold VGS-th of the first detection module Q1 is in the range of [0.7, 1.7] V, and both the first power supply ANT_POWER1 and the second power supply ANT_POWER2 are 3.3 V power supplies. In this embodiment, when the external antenna is short-circuited, it is equivalent to EXT_ANT being directly connected to GND at this time (that is, the detection node A is directly grounded). At this time, the G-pole voltage of the first detection module Q1 is 0 V, and there is no voltage difference between the G-pole and the S-pole (since the S-pole is grounded, the voltage difference is the G-pole voltage), so the D-S stage is not conducting, and GPS_ANT_SHORT_DET is at a high level of 3.3 V. When the external antenna is not connected to the RF connector, it is equivalent to EXT_ANT being open-circuited. The first resistor module R1 and the second resistor module R2 divide the voltage of the 3.3 V power supply. Since the resistance value of the first resistor module R1 is much smaller than that of the second resistor module R2, the G-pole voltage of the first detection module Q1 is greater than the conduction threshold at this time, and the D-S is conducting. At this time, GPS_ANT_SHORT_DET is at a low level. When the external antenna is in normal use and not open-circuited, since the external antenna is an active device with a power consumption of 9 mA @ 3.3 V, at this time, the second resistor module R2 and the external antenna to which EXT_ANT is connected are in parallel, equivalent to a load impedance composed of the parallel connection of 36 Ω (active antenna) and 1 MΩ, approximately 35 Ω. Since the first resistor module R1 is only 20 Ω, the G-pole voltage of the first detection module Q1 is about 2.1 V at this time. The G-pole voltage of the first detection module Q1 is greater than the conduction threshold, and the D-S is conducting, and GPS_ANT_SHORT_DET is at a low level.

[0047] The above technical solution uses the first resistor module, the second resistor module and the first detection module to form the second detection circuit, which has a simple structure and can accurately detect whether the external antenna is short-circuited, and can provide a relatively reliable basis for the switching between the internal and external antennas.

[0048] Exemplarily, the second detection unit further includes an inductor module, and the inductor module is connected in series between the first resistor module and the detection node. In the embodiment shown in Figure 3 , the inductor module L1 is connected in series between the first resistor module and the detection node. The inductor module can play a filtering role to ensure the power supply quality of the external antenna.

[0049] Exemplarily, the second detection unit further includes a third resistor module, and the third resistor module is connected in series between the second power supply and the first sampling node.

[0050] ForFigure 3 Take the illustrated embodiment as an example for description. As Figure 3 shown, the third resistor module R3 is connected in series between the second power supply ANT_POWER2 and the first sampling node B.

[0051] Through the above technical solution, by setting the third resistor module, the overall device can be protected, which helps to improve the service life of the device.

[0052] Exemplarily, the device further includes a first diode and a second diode. The first diode is connected in series between the first detection unit and the control pin of the RF switching module, and the second diode is connected in series between the second detection unit and the control pin of the RF switching module.

[0053] Take Figure 2 the circuit diagram of the illustrated embodiment as an example for description. In this embodiment, the device further includes a first diode D1 and a second diode D2. The first detection signal GPS_ACTIVE _ANT _DET is transmitted to the control pin VCTL via the first diode D1. The second detection signal GPS _ANT_SHORT_DET is transmitted to the control pin VCTL via the second diode.

[0054] In some embodiments, both the first diode and the second diode may be Schottky diodes.

[0055] Through the above technical solution, by setting the first diode connected in series between the first detection unit and the control pin of the RF switching module and the second diode connected in series between the second detection unit and the control pin of the RF switching module, the two signals can be prevented from pouring into each other and interfering, thereby ensuring the reliability of the device operation.

[0056] Exemplarily, the first detection unit includes a fourth resistor module, a fifth resistor module, a sixth resistor module, and a second detection module; the first end of the fourth resistor module is connected to the third power supply, and the second end of the fourth resistor module is connected to the detection node; the first end of the fifth resistor module is connected to the second end of the fourth resistor module, and the second end of the fifth resistor module is grounded; the control end of the second detection module is connected to the second end of the fourth resistor module, the first end of the second detection module is connected to the fourth power supply, the second end of the second detection module is connected to the first end of the sixth resistor module via the second sampling node, the second end of the sixth resistor module is grounded, and the second sampling node is connected to the control pin of the RF switching module.

[0057] In the solution of this example, when the external antenna is connected to the RF connector, the voltage of the second sampling node does not meet the conduction condition of the second detection module, and the first end and the second end of the second detection module are in a non-conducted state. The first detection signal output by the second sampling node is a valid signal. When the external antenna is not connected to the RF connector, the voltage of the second sampling node meets the conduction condition of the second detection module, and the first end and the second end of the second detection module are in a conducted state. The first detection signal output by the second sampling node is an invalid signal.

[0058] Optionally, the second detection module can be selected according to actual needs, as long as it meets the above conduction requirements. In some embodiments, the second detection module is an N-channel metal oxide semiconductor (NMOS) field effect transistor (which can be simply referred to as an NMOS transistor). In this embodiment, the voltage of the second sampling node meeting the conduction condition of the second detection module means that the voltage of the second sampling node is greater than or equal to the conduction threshold of the NMOS transistor. At this time, the voltage of the G pole of the NMOS transistor is greater than or equal to the conduction threshold, and the D pole and the S pole are conducted. The voltage of the second sampling node not meeting the conduction condition of the second detection module means that the voltage of the second sampling node is less than the conduction threshold of the NMOS transistor. At this time, the voltage of the G pole of the NMOS transistor is less than the conduction threshold, and the D pole and the S pole are cut off.

[0059] As described above, when the external antenna is connected to the RF connector, the first detection signal output by the second sampling node is a valid signal. When the external antenna is not connected to the RF connector, the first detection signal output by the second sampling node is an invalid signal. It can be understood that when the external antenna is connected to the RF connector, the first end and the second end of the second detection module are in a non-conducted state. At this time, it can be equivalently considered that the second sampling node is directly grounded, and the voltage of the second sampling node is the low level 0V. When the external antenna is not connected to the RF connector, the first end and the second end of the second detection module are in a conducted state. At this time, the voltage of the second sampling node is the high level 3.3V. In other words, in the solution of this embodiment, the valid signal is the low level, and the invalid signal is the high level.

[0060] Figure 4 The circuit schematic diagram of the first detection unit according to an embodiment of the present application is shown. As Figure 4As shown, the first detection unit includes a fourth resistor module R4, a fifth resistor module R5, a sixth resistor module R6, and a second detection module Q2, and the second detection module Q2 is an NMOS transistor. The first end of the fourth resistor module R4 is connected to the third power supply ANT_POWER3, and the second end of the fourth resistor module R4 is connected to the detection node A (in this embodiment, the second end of R4 is connected to the detection node A via EXT_ANT); the first end of the fifth resistor module R5 is connected to the second end of the fourth resistor module R4, and the second end of the fifth resistor module R5 is grounded; the control terminal G of the second detection module Q2 is connected to the second end of the fourth resistor module R4, the first terminal D of the second detection module Q2 is connected to the power supply, and the second terminal S of the second detection module Q2 is connected to the first end of the sixth resistor module R6 via the second sampling node C, and the second end of the sixth resistor module R6 is grounded. The second sampling node C is connected to the control pin of the radio frequency switching module, and the first detection signal GPS_ACTIVE _ANT _DET is received by the control pin.

[0061] In Figure 4 In the shown embodiment, the second end of the fourth resistor module R4 is connected to the detection node A, so their voltages are equal. In this case, the voltage of the G pole of the second detection module Q2 is equal to the voltage of the detection node A. When the D pole and the S pole are cut off, the first detection signal GPS_ACTIVE _ANT _DET is at a low level, and when the D pole and the S pole are conducting, the first detection signal GPS_ACTIVE _ANT _DET is at a high level.

[0062] Optionally, the resistance value relationship between the fourth resistor module and the fifth resistor module satisfies the following conditions: when the fourth resistor module and the fifth resistor module are in series, the voltage value divided by the fifth resistor module satisfies the conduction condition of the second detection module, and when the fifth resistor module is in parallel with the external antenna, the voltage value divided by the fifth resistor module does not satisfy the conduction condition of the second detection module. Figure 4For example, when the external antenna is not connected to the RF connector, EXT_ANT is in an open circuit state. At this time, the fourth resistor module R4 and the fifth resistor module R5 are connected in series. In this case, the G-pole voltage of the second detection module Q2 is equal to the voltage divided by the fifth resistor module R5. Since when the fourth resistor module R4 and the fifth resistor module R5 are connected in series, the voltage value divided by the fifth resistor module R5 satisfies the conduction condition of the second detection module. At this time, the D-pole and S-pole of the second detection module Q2 are conducting, and the second sampling node C outputs a high level. When the external antenna is connected to the RF connector and the external antenna is short-circuited, it can be equivalent to the G-pole of the second detection module Q2 being grounded. At this time, the D-pole and S-pole of the second detection module Q2 are cut off, and the second sampling node C outputs a low level. When the external antenna is connected to the RF connector and the external antenna is working normally, it can be equivalent to the fifth resistor module R5 being connected in parallel with the external antenna. As described above, the voltage value divided by the fifth resistor module R5 does not satisfy the conduction condition of the second detection module. At this time, the D-pole and S-pole of the second detection module Q2 are cut off, and the second sampling node C outputs a low level. This solution can improve the detection accuracy of the first detection module by restricting the resistance value relationship between the fourth resistor module and the fifth resistor module, which helps to provide a more accurate basis for the switching between the internal and external antennas. The present application does not limit the specific resistance values of the fourth resistor module and the fifth resistor module, as long as they satisfy the above relationship.

[0063] In a specific embodiment, use Figure 4The circuit structure shown is used as the second detection module. In this embodiment, the power consumption of the external antenna is 9 mA @ 3.3 V, the resistance value of the fourth resistor module R4 is 330 kΩ, the resistance value of the fifth resistor module R5 is 2.2 MΩ, the conduction threshold VGS-th of the second detection module Q2 is in the range of [0.7, 1.7] V, and the third power supply ANT_POWER3 and the fourth power supply ANT_POWER4 are 3.3 V power supplies. In this embodiment, when the external antenna is not connected to the RF connector, it is equivalent to an open circuit of EXT_ANT. The fourth resistor module R4 and the fifth resistor module R5 divide the voltage of the 3.3 V power supply. The voltage divided by the fifth resistor module R5 is approximately 2.8 V, which is greater than the conduction threshold of the second detection module Q2. The D and S poles of the second detection module Q2 are turned on, and GPS_ACTIVE_ANT_DET is at a high level of 3.3 V. When the external antenna is connected to the RF connector and the external antenna is short-circuited, it is equivalent to EXT_ANT being grounded. At this time, the voltage of the G pole is close to 0 V, which is less than the conduction threshold of the second detection module Q2. The D and S poles of the second detection module Q2 are cut off, and GPS_ACTIVE_ANT_DET is at a low level. When the external antenna is connected to the RF connector and the external antenna is operating normally, since the external antenna is an active device with a power consumption of 9 mA @ 3.3 V, which is equivalent to an impedance of 36 Ω (active antenna), the parallel equivalent impedance of this external antenna and R5 - 2.2 MΩ (the high impedance can be ignored) is about 34 Ω. It divides the voltage of the 3.3 V power supply with the R4 - 330 K resistor. The voltage divided by the G pole of the second detection module Q2 is very small, and the voltage of the G pole is about 0.18 V, which is less than the conduction threshold of the second detection module Q2. The D and S poles of the second detection module Q2 are cut off, and GPS_ACTIVE_ANT_DET is at a low level.

[0064] The above technical solution uses the fourth resistor module, the fifth resistor module, the sixth resistor module and the second detection module to form the first detection circuit. The structure is simple and can accurately detect whether the external antenna is connected to the RF connector, providing a relatively reliable basis for the switching between the internal and external antennas.

[0065] The working principle of the device of the present application will be introduced below with a specific embodiment. In this embodiment, the overall device adopts Figure 2 the circuit structure of the embodiment shown, and the first detection module adopts Figure 4 the circuit structure shown, and the second detection module adopts Figure 3 the circuit structure shown. As can be seen from the above, the short-circuit signal is a high-level signal, and the non-short-circuit signal is a low-level signal. The valid signal is a low level, and the invalid signal is a high level. Thus, the following truth table can be obtained.

[0066] Table 1 Truth Table

[0067]

[0068] In Table 1, 0 represents a low level and 1 represents a high level. In the solution of this embodiment, when the external antenna is inserted into the RF connector CON1, it is equivalent to connecting the EXT_ANT to the external antenna. The high and low levels (0V / 3.3V) of GPS_ACTIVE_ANT_DET and GPS_ANT_SHOR_DET output by the above detection system are transmitted to the VCTL pin of the chip. According to the high and low levels of these two signals, GPS_ACTIVE_ANT_DET and GPS_ANT_SHOR_DET, the chip is controlled to switch to the RF1 or RF2 antenna path. Specifically, when the external antenna is short-circuited, GPS_ACTIVE_ANT_DET is at a high level and GPS_ANT_SHOR_DET is at a low level. At this time, VCTL is at a high level (1.35~3V). In this case, the built-in antenna is used for network communication. When the external antenna is not connected, GPS_ACTIVE_ANT_DET is at a low level and GPS_ANT_SHOR_DET is at a high level. At this time, VCTL is at a high level (1.35~3V). In this case, the built-in antenna is used for network communication. When the external antenna is working properly (that is, the external antenna is connected to the RF connector and the external antenna is not short-circuited), GPS_ACTIVE_ANT_DET is at a low level and GPS_ANT_SHOR_DET is at a low level. At this time, VCTL is at a low level (0.1~0.45V). In this case, the external antenna is used for network communication.

[0069] According to another aspect of the embodiments of the present application, a wireless network device is provided, and the wireless network device includes the internal and external antenna automatic switching device of any of the above embodiments.

[0070] Optionally, the wireless network device includes, but is not limited to, a locator, a telephone, a darkroom network test instrument, or other communication network devices.

[0071] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the orientation words such as "front", "rear", "upper", "lower", "left", "right", "lateral", "vertical", "perpendicular", "horizontal", and "top", "bottom", etc. is usually based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description. Without contrary explanation, these orientation words do not indicate and imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the protection scope of the present application; the orientation words "inside" and "outside" refer to the inside and outside relative to the contour of each component itself.

[0072] For ease of description, regional relative terms such as "above", "over", "on the upper surface", "upper" etc. can be used here to describe the regional positional relationship of one or more components or features shown in the figure with other components or features. It should be understood that regional relative terms not only include the orientation of components described in the figure, but also different orientations during use or operation. For example, if the components in the attached figure are inverted as a whole, then the component "above other components or features" or "over other components or features" will include the situation where the component is "below other components or structures" or "under other components or structures". Thus, the exemplary term "above" can include both the orientations of "above" and "below". In addition, these components or features can also be positioned at other different angles (such as rotated 90 degrees or other angles), and this document intends to cover all such situations.

[0073] It should be noted that the terms used here are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used here, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should also be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, components, parts and / or combinations thereof.

[0074] It should be noted that the terms "first", "second", etc. in the description, claims and above-mentioned attached figures of the present application are used to distinguish similar objects and do not necessarily have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances so that the embodiments of the present application described here can be implemented in an order other than those illustrated or described here.

[0075] The present application has been described through the above embodiments, but it should be understood that the above embodiments are only for the purpose of illustration and example, and are not intended to limit the present application within the scope of the described embodiments. In addition, those skilled in the art can understand that the present application is not limited to the above embodiments, and more variations and modifications can be made according to the teachings of the present application, and these variations and modifications all fall within the scope claimed by the present application. The protection scope of the present application is defined by the appended claims and their equivalent scope.

Claims

1. An automatic switching device for internal and external antennas, characterized in that, Comprising: A radio frequency switching module, a first detection unit, a built-in antenna, and a radio frequency connector for connecting an external antenna; A first radio frequency pin of the radio frequency switching module is connected to a first end of the radio frequency connector, a second radio frequency pin of the radio frequency switching module is connected to the built-in antenna, and a control pin of the radio frequency switching module is connected to the first detection unit to receive a first detection signal sent by the first detection unit; The first detection unit is connected to the first end of the radio frequency connector via a detection node to detect whether the external antenna is connected to the radio frequency connector; a second end of the radio frequency connector is grounded; It further includes a second detection unit, the second detection unit is connected to the radio frequency connector via the detection node to detect whether the external antenna is short-circuited; the control pin of the radio frequency switching module is connected to the second detection unit to receive a second detection signal sent by the second detection unit; The second detection unit includes a first resistor module, a second resistor module, and a first detection module; A first end of the first resistor module is connected to a first power supply, and a second end of the first resistor module is connected to the detection node; A first end of the second resistor module is connected to the second end of the first resistor module, and a second end of the second resistor module is grounded; A control end of the first detection module is connected to the second end of the first resistor module, a first end of the first detection module is connected to a second power supply via a first sampling node, a second end of the first detection module is grounded, and the first sampling node is connected to the control pin of the radio frequency switching module; The first detection module is an N-channel metal oxide semiconductor field effect transistor; The second detection unit further includes an inductor module, and the inductor module is connected in series between the first resistor module and the detection node.

2. The automatic switching device for internal and external antennas according to claim 1, characterized in that The second detection unit further includes a third resistor module, and the third resistor module is connected in series between the second power supply and the first sampling node.

3. The automatic switching device for internal and external antennas according to claim 1 or 2, characterized in that, The device further includes a first diode and a second diode, the first diode is connected in series between the first detection unit and the control pin of the radio frequency switching module, and the second diode is connected in series between the second detection unit and the control pin of the radio frequency switching module.

4. The automatic switching device for internal and external antennas according to claim 1 or 2, characterized in that, The first detection unit includes a fourth resistor module, a fifth resistor module, a sixth resistor module, and a second detection module; A first end of the fourth resistor module is connected to a third power supply, and a second end of the fourth resistor module is connected to the detection node; A first end of the fifth resistor module is connected to the second end of the fourth resistor module, and a second end of the fifth resistor module is grounded; A control end of the second detection module is connected to the second end of the fourth resistor module, a first end of the second detection module is connected to a fourth power supply, a second end of the second detection module is connected to a first end of the sixth resistor module via a second sampling node, and a second end of the sixth resistor module is grounded; the second sampling node is connected to the control pin of the radio frequency switching module.

5. The automatic switching device for internal and external antennas according to claim 4, characterized in that The second detection module is an N-channel metal oxide semiconductor field effect transistor.

6. A wireless network device, characterized in that, Including the built-in and external antenna automatic switching device according to any one of claims 1-5.

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