An antenna switching antenna redundancy circuit and camera thereof

Abstract

The utility model discloses an antenna switching's antenna redundancy circuit and camera thereof, camera includes a casing, is equipped with a circuit board and a plurality of antennas of setting in the preset position in casing, and the integrated main control circuit, wireless circuit and antenna redundancy circuit on the circuit board, the signal strength of current antenna is acquired and is transmitted to main control circuit through the current connection state of antenna redundancy circuit of wireless circuit, when the signal strength is lower than threshold value, the connection state of each antenna is controlled antenna redundancy circuit polling switch of main control circuit, when switching every time, the signal strength of current antenna is acquired and is transmitted to main control circuit once by wireless circuit, main control circuit compares the signal strength of each antenna, and according to the strongest signal intensity control antenna redundancy circuit connects corresponding antenna. According to the signal strength of each antenna, the antenna of signal strength maximum is switched automatically to communicate, solved the problem that single antenna is caused to position blind angle and leads to communication to be blocked.

Description

Technical Field

[0001] This utility model relates to the field of electronic technology, and in particular to an antenna redundancy circuit for antenna switching and its camera. Background Technology

[0002] Currently, network cameras on the market typically use a single antenna to transmit data, such as 1T1R (single transmit, single receive) transmission. The antenna type is generally a full-line antenna with a gain of around 1dBi. Due to the influence of structural assembly, the signal strength exhibited by the antenna varies significantly at different angles; this can even lead to performance degradation, weakened signal strength, or no signal transmission at certain angles.

[0003] To reduce the impact of antenna dead zones or defects on data transmission, current methods focus on improving antenna efficiency, gain, and conducted power. This places further demands on antenna size and materials. For example, changing the antenna material, such as using a low-dielectric-constant substrate or increasing the antenna's size, increases cost. Increasing the wireless module's transmit power inevitably leads to higher heat generation during normal operation, and network camera devices cannot tolerate excessively high internal temperatures, otherwise thermal noise issues will occur in the image. Alternatively, using a 2T2R (dual-transmit, dual-receive) wireless module with a different antenna design will also increase costs. Utility Model Content

[0004] To address the aforementioned technical problems, this utility model provides an antenna redundancy circuit for antenna switching and its camera, thereby solving the problem of communication obstruction caused by dead angles in existing single antennas.

[0005] This utility model embodiment provides an antenna redundancy circuit for antenna switching, which is set on a circuit board inside the camera housing and connects a main control circuit, a wireless circuit, and several antennas on the circuit board. The antenna redundancy circuit includes a first switching module, a second switching module, and a third switching module. The first switching module is connected to the second switching module, the third switching module, and the wireless circuit. The first switching module, the second switching module, and the third switching module are all connected to the main control circuit.

[0006] The first switching module switches the main antenna path according to the first control signal and the second control signal output by the main control circuit;

[0007] The second switching module switches a portion of the antenna sub-paths according to the third and fourth control signals output by the main control circuit, and connects to the corresponding antenna;

[0008] The third switching module switches another part of the antenna sub-paths according to the third control signal and the fourth control signal, and connects to the corresponding antenna.

[0009] Optionally, in the antenna redundancy circuit for antenna switching, the first switching module includes a first single-pole double-throw switch, a first inductor, a first capacitor, and a second capacitor.

[0010] The VC1 pin of the first single-pole double-throw switch is connected to the main control circuit. The RFC pin of the first single-pole double-throw switch is connected to one end of the first inductor and one end of the second capacitor. The other end of the first inductor is connected to one end of the first capacitor and the wireless circuit. The VC2 pin of the first single-pole double-throw switch is connected to the main control circuit. The RF1 pin of the first single-pole double-throw switch is connected to the second switching module. The RF2 pin of the first single-pole double-throw switch is connected to the third switching module. The GND pin of the first single-pole double-throw switch, the other end of the first capacitor, and the other end of the second capacitor are all grounded.

[0011] Optionally, in the antenna redundancy circuit for antenna switching, the second switching module includes a second single-pole double-throw switch, a second inductor, a third inductor, a third capacitor, a fourth capacitor, a fifth capacitor, and a sixth capacitor.

[0012] The VC1 pin of the second single-pole double-throw switch is connected to the main control circuit. The RFC pin of the second single-pole double-throw switch is connected to the RF1 pin of the first single-pole double-throw switch. The VC2 pin of the second single-pole double-throw switch is connected to the main control circuit. The RF1 pin of the second single-pole double-throw switch is connected to one end of the second inductor and one end of the third capacitor. The other end of the second inductor is connected to one end of the fourth capacitor and the first antenna. The GND pin of the second single-pole double-throw switch, the other end of the third capacitor, and the other end of the fourth capacitor are all grounded. The RF2 pin of the second single-pole double-throw switch is connected to one end of the third inductor and one end of the fifth capacitor. The other end of the third inductor is connected to one end of the sixth capacitor and the second antenna. The other ends of the fifth capacitor and the other ends of the sixth capacitor are all grounded.

[0013] Optionally, in the antenna redundancy circuit for antenna switching, the second switching module further includes a fourth inductor, a seventh capacitor, and an eighth capacitor.

[0014] One end of the fourth inductor is connected to the RFC pin of the second single-pole double-throw switch and one end of the eighth capacitor. The other end of the fourth inductor is connected to one end of the seventh capacitor and the RF1 pin of the first single-pole double-throw switch. The other ends of the seventh capacitor and the eighth capacitor are both grounded.

[0015] Optionally, in the antenna redundancy circuit for antenna switching, the third switching module includes a third single-pole double-throw switch, a fifth inductor, a sixth inductor, a ninth capacitor, a tenth capacitor, an eleventh capacitor, and a twelfth capacitor.

[0016] The VC1 pin of the third single-pole double-throw switch is connected to the main control circuit; the RFC pin of the third single-pole double-throw switch is connected to the RF2 pin of the first single-pole double-throw switch; the VC2 pin of the third single-pole double-throw switch is connected to the fourth control pin of the main control chip; the RF1 pin of the third single-pole double-throw switch is connected to one end of the fifth inductor and one end of the ninth capacitor; the other end of the fifth inductor is connected to one end of the tenth capacitor and the third antenna; the GND pin of the third single-pole double-throw switch, the other end of the ninth capacitor, and the other end of the tenth capacitor are all grounded; the RF2 pin of the third single-pole double-throw switch is connected to one end of the sixth inductor and one end of the eleventh capacitor; the other end of the sixth inductor is connected to one end of the twelfth capacitor and the fourth antenna; the other ends of the eleventh capacitor and the other ends of the twelfth capacitor are all grounded.

[0017] Optionally, in the antenna redundancy circuit for antenna switching, the third switching module further includes a seventh inductor, a thirteenth capacitor, and a fourteenth capacitor.

[0018] One end of the seventh inductor is connected to the RFC pin of the third single-pole double-throw switch and one end of the fourteenth capacitor. The other end of the seventh inductor is connected to one end of the thirteenth capacitor and the RF2 pin of the first single-pole double-throw switch. The other ends of the thirteenth capacitor and the fourteenth capacitor are both grounded.

[0019] A second aspect of this utility model provides an antenna-switching camera, including a housing, a circuit board inside the housing, a main control circuit and a wireless circuit integrated on the circuit board, wherein the housing also contains a plurality of antennas arranged in preset positions, and the circuit board also integrates the antenna redundancy circuit; the main control circuit is connected to the wireless circuit and the antenna redundancy circuit, and the antenna redundancy circuit is connected to the wireless circuit and the plurality of antennas;

[0020] The wireless circuit obtains the signal strength of the currently connected antenna through the current connection status of the antenna redundancy circuit and transmits it to the main control circuit.

[0021] When the main control circuit determines that the signal strength is lower than the threshold, it controls the antenna redundancy circuit to poll and switch the connection status of each antenna. Each time the connection is switched, the wireless circuit acquires the signal strength of the currently connected antenna and transmits it to the main control circuit. The main control circuit compares the signal strength of each antenna and controls the antenna redundancy circuit to connect the corresponding antenna based on the strongest signal strength.

[0022] In the aforementioned antenna-switching camera, the main control circuit includes a main control chip, and the wireless circuit includes a wireless chip; the four control pins of the main control chip are connected to the antenna redundancy circuit, the communication pin of the main control chip is connected to the data pin of the wireless chip, and the antenna pin of the wireless chip is connected to the antenna redundancy circuit.

[0023] In the technical solution provided by this utility model embodiment, the antenna-switching camera includes a housing. Inside the housing is a circuit board and several antennas positioned at preset locations. The circuit board integrates a main control circuit, a wireless circuit, and an antenna redundancy circuit. The main control circuit connects the wireless circuit and the antenna redundancy circuit, and the antenna redundancy circuit connects the wireless circuit and the several antennas. The wireless circuit obtains the signal strength of the currently connected antenna through the current connection status of the antenna redundancy circuit and transmits it to the main control circuit. When the main control circuit determines that the signal strength is below a threshold, it controls the antenna redundancy circuit to poll and switch the connection status of each antenna. Each time a switch occurs, the wireless circuit obtains the signal strength of the currently connected antenna and transmits it to the main control circuit. The main control circuit compares the signal strength of each antenna and controls the antenna redundancy circuit to connect to the corresponding antenna based on the strongest signal strength. By determining the signal strength through the main control circuit and combining it with the switching of the antenna redundancy circuit, the system can automatically switch to the antenna with the strongest signal strength for communication. This method of selecting antennas in different orientations solves the problem of communication obstruction caused by a single antenna's dead angle. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the antenna switching camera in an embodiment of this utility model.

[0025] Figure 2 This is a circuit diagram of the main control circuit and the wireless circuit in an embodiment of this utility model.

[0026] Figure 3 This is a circuit diagram of the antenna redundancy circuit in an embodiment of this utility model. Detailed Implementation

[0027] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. All other embodiments of the present utility model obtained by those skilled in the art without creative effort are within the scope of protection of the present utility model.

[0028] It is readily understood that relational terms such as "first" and "second" are used merely to distinguish one entity, operation, or direction from another, without requiring or implying any actual relationship or order between these entities, operations, or directions. The directional terms such as "up," "down," "left," "right," "front," "back," "front," "back," "top," and "bottom," mentioned or possibly used in this specification, are defined relative to the constructions shown in the accompanying drawings. They are relative concepts and may therefore vary depending on their location and usage. Therefore, these or other directional terms should not be construed as restrictive. In the following description, various parameters and components are described for embodiments of different constructions. These specific parameters and components are merely examples and do not limit the embodiments of this application.

[0029] Please see Figure 1 The antenna-switching camera provided in this embodiment includes a housing, within which a circuit board and several antennas positioned at preset locations are disposed. The circuit board integrates a main control circuit 10, a wireless circuit 20, and an antenna redundancy circuit 30. The main control circuit 10 connects to the wireless circuit 20 and the antenna redundancy circuit 30, and the antenna redundancy circuit 30 connects to the wireless circuit 20 and the several antennas. The wireless circuit 20 obtains the signal strength of the currently connected antenna through the current connection status of the antenna redundancy circuit 30 and transmits it to the main control circuit 10. When the main control circuit 10 determines that the signal strength is below a threshold, it controls the antenna redundancy circuit 30 to poll and switch the connection status (i.e., connected or disconnected) of each antenna. Each time a switch occurs, the wireless circuit 20 obtains the signal strength of the currently connected antenna and transmits it to the main control circuit 10. The main control circuit 10 compares the signal strengths of each antenna and controls the antenna redundancy circuit 30 to connect the corresponding antenna based on the strongest signal strength.

[0030] By judging the signal strength through the main control circuit 10 and switching the antenna redundancy circuit 30, the system can automatically switch to the antenna with the strongest signal strength for communication based on the signal strength of each antenna. This method of selecting antennas in different directions solves the problem of communication obstruction caused by a single antenna being in a dead angle.

[0031] It's important to understand that the preset antenna positions are adjusted based on requirements and quantity. For example, with four antennas, they can be located in the four directions of the camera; this is not a limitation here. The internal circuit structure of the main control circuit 10 and the wireless circuit 20 remains unchanged. The reserved pins on the main control circuit 10 are used, and corresponding judgment and control functions are added. Other circuit modules, such as the power supply circuit, are also on the circuit board, but will not be elaborated here. The antenna redundancy circuit 30 can also be applied to other electronic devices that use multiple antennas for communication, while simultaneously increasing the connection method between the main control circuit, the wireless circuit, and the antenna redundancy circuit 30 in that electronic device.

[0032] In this embodiment, as Figure 2 As shown, the main control circuit 10 includes a main control chip U1. The four control pins of the main control chip U1 are connected to the antenna redundancy circuit 30, and the communication pins of the main control chip U1 are connected to the wireless circuit 20. The main control chip U1 is a chip commonly used in cameras, preferably the T23 series from Ingenic Semiconductor. The four control pins are specifically pin 69 (GMAC_TXCLK_MIPI_SEL0_I2S_DAC_MCLK_SLCD_D0_PB06), pin 60 (GMAC_PHY_CLK_MIPI_SEL1_I2S_DAC_BCLK_SLCD_D1_PB07), pin 66 (GMAC_TXEN_MSC1_CLK_I2S_DAC_LRCK_SLCD_D2_PB08), and pin 62 (GMAC_RXDV_MSC1_CMD_I2S_SDTI_SLCD_D3_PB09). Four control pins output the first control signal GPIO1, the second control signal GPIO2, the third control signal GPIO3, and the fourth control signal GPIO4 respectively to control the connection status inside the antenna redundancy circuit 30, allowing the corresponding antenna to be connected. The communication pins include pin 35 (i.e., USBOPN pin) and pin 36 (i.e., USBOPP pin). That is, the wireless circuit 20 transmits the signal received by the corresponding antenna to the main control chip through the USB_DM and USB_DP signals (differential signals) on the communication pins, and the transmit signal output by the main control chip is transmitted to the wireless circuit 20 through the USB_DM and USB_DP signals.

[0033] The wireless circuit 20 includes a wireless chip U2. The antenna pin of the wireless chip U2 is connected to the antenna redundancy circuit 30, and the data pin of the wireless chip U2 is connected to the communication pin of the main control module. The wireless chip U2 is a communication chip commonly used in cameras, preferably a 6621-SL WiFi chip. The antenna pin is specifically the RF pin (pin 6). The data pins include a DM+ pin (pin 2) and a DP+ pin (pin 3). The DM+ pin is connected to the USB0PN pin of the main control chip, and the DP+ pin is connected to the USB0PP pin of the main control chip. The data pins can use USB (SDIO can also be used in specific implementations) to transmit and receive signals with the main control chip. That is, the signal received by the corresponding antenna is input through the antenna pin and output from the data pin to the communication pin of the main control chip. The main control chip can then determine the signal strength based on this signal. The main control chip outputs a transmit signal from its communication pin, receives it through the data pin of the wireless chip U2, and then outputs it from the antenna pin of the wireless chip. The signal is then transmitted to the corresponding antenna for transmission through the antenna redundancy circuit 30.

[0034] It should be understood that the other pin connections of the main control chip U1 and the wireless chip U2 are existing technologies, and only the improved connection method is described here.

[0035] like Figure 3 As shown, the antenna redundancy circuit 30 includes a first switching module 31, a second switching module 32, and a third switching module 33. The first switching module 31 is connected to the second switching module 32, the third switching module 33, and the wireless circuit. All three modules are connected to the main control circuit. The first switching module 31 switches the main antenna path according to the first control signal GPIO1 and the second control signal GPIO2 output by the main control circuit 10. The second switching module 32 switches a portion of the antenna sub-paths according to the third control signal GPIO3 and the fourth control signal GPIO3 output by the main control circuit 10, connecting the corresponding antenna. The third switching module 33 switches another portion of the antenna sub-paths according to the third control signal GPIO3 and the fourth control signal GPIO3, connecting the corresponding antenna.

[0036] In practical implementation, the type of switch in each switching module can be selected according to the number of antennas. For example, with 6 antennas, the first switching module can use a single-pole double-throw switch, while the second switching module 32 and the third switching module 33 can use a single-pole triple-throw switch, thus dividing the system into two main antenna paths. Each main antenna path corresponds to three antenna sub-paths, with each sub-path connecting to one antenna. Alternatively, the first switching module can use a single-pole triple-throw switch, while the second switching module 32 and the third switching module 33 can use a single-pole double-throw switch, resulting in three main antenna paths. Each main antenna path corresponds to two antenna sub-paths, with each sub-path connecting to one antenna. If the number of antennas is odd, one antenna sub-path can be left unused. The main antenna paths are used to divide several antennas into several parts, and the antenna sub-paths are used to connect the corresponding antennas.

[0037] This embodiment takes four antennas as an example. The first switching module 31 includes a first single-pole double-throw switch S1, a first inductor L1, a first capacitor C1, and a second capacitor C2. The VC1 pin of the first single-pole double-throw switch S1 is connected to the first control pin (pin 69) of the main control chip U1. The RFC pin of the first single-pole double-throw switch S1 is connected to one end of the first inductor L1 and one end of the second capacitor C2. The other end of the first inductor L1 is connected to one end of the first capacitor C1 and the ANT pin of the wireless chip U2. The VC2 pin of the first single-pole double-throw switch S1 is connected to the second control pin (pin 60) of the main control chip U1. The RF1 pin of the first single-pole double-throw switch S1 is connected to the second switching module 32. The RF2 pin of the first single-pole double-throw switch S1 is connected to the third switching module 33. The GND pin of the first single-pole double-throw switch S1, the other end of the first capacitor C1, and the other end of the second capacitor C2 are all grounded.

[0038] The first single-pole double-throw switch S1 is preferably a high-frequency, low-loss SPDT (single-pole double-throw) switch of model TPUPG2179TB. The first inductor L1, the first capacitor C1, and the second capacitor C2 form a first-stage π-type matching to suppress spurious signals on the link. When the first control signal GPIO1 is active (active low) and the second control signal GPIO2 is inactive (inactive high), the RFC pin of the first single-pole double-throw switch S1 is connected to the RF1 pin, and the main circuit of the first antenna is connected, indicating that subsequent selection will be made between the first antenna ANT1 and the second antenna ANT2. When the first control signal GPIO1 is inactive and the second control signal GPIO2 is active, the RFC pin of S1 is connected to the RF2 pin, and the main circuit of the second antenna is connected, indicating that subsequent selection will be made between the third antenna ANT3 and the fourth antenna ANT4.

[0039] The second switching module 32 includes a second single-pole double-throw switch S2, a second inductor L2, a third inductor L3, a third capacitor C3, a fourth capacitor C4, a fifth capacitor C5, and a sixth capacitor C6. The VC1 pin of the second single-pole double-throw switch S2 is connected to the third control pin (pin 66) of the main control chip U1. The RFC pin of the second single-pole double-throw switch S2 is connected to the RF1 pin of the first single-pole double-throw switch S1. The VC2 pin of the second single-pole double-throw switch S2 is connected to the fourth control pin (pin 62) of the main control chip U1. The RF1 pin of the second single-pole double-throw switch S2... Connect one end of the second inductor L2 to one end of the third capacitor C3. Connect the other end of the second inductor L2 to one end of the fourth capacitor C4 and the first antenna ANT1. The GND pin of the second single-pole double-throw switch S2, the other end of the third capacitor C3, and the other end of the fourth capacitor C4 are all grounded. Connect the RF2 pin of the second single-pole double-throw switch S2 to one end of the third inductor L3 and one end of the fifth capacitor C5. Connect the other end of the third inductor L3 to one end of the sixth capacitor C6 and the second antenna ANT2. The other ends of the fifth capacitor C5 and the other ends of the sixth capacitor C6 are all grounded.

[0040] The second single-pole double-throw switch S2 is preferably a high-frequency, low-loss SPDT (single-pole double-throw) switch of model TPUPG2179TB. The π-type matching formed by the second inductor L2, the third capacitor C3, and the fourth capacitor C4 is used for matching and debugging the first antenna ANT1. The π-type matching formed by L3, C5, and C6 is used for matching and debugging the second antenna ANT2. When the third control signal GPIO3 is active (low level) and the fourth control signal GPIO4 is inactive (high level), the RFC pin of S2 is connected to the RF1 pin, and the first antenna is connected. When the third control signal GPIO3 is inactive and the fourth control signal GPIO4 is active, the RFC pin of S2 is connected to the RF2 pin, and the second antenna is connected.

[0041] Preferably, the second switching module 32 further includes a fourth inductor L4, a seventh capacitor C7, and an eighth capacitor C8; one end of the fourth inductor L4 is connected to the RFC pin of the second single-pole double-throw switch S2 and one end of the eighth capacitor C8, and the other end of the fourth inductor L4 is connected to one end of the seventh capacitor C7 and the RF1 pin of the first single-pole double-throw switch S1. The other ends of the seventh capacitor C7 and the eighth capacitor C8 are both grounded. The π-type matching formed by L4, C7, and C8, combined with the π-type matching of L1, C1, and C2, is used to match the impedance across S1.

[0042] The third switching module 33 includes a third single-pole double-throw switch S3, a fifth inductor L5, a sixth inductor L6, a ninth capacitor C9, a tenth capacitor C10, an eleventh capacitor C11, and a twelfth capacitor C12. The VC1 pin of the third single-pole double-throw switch S3 is connected to the third control pin (pin 66) of the main control chip U1; the RFC pin of the third single-pole double-throw switch S3 is connected to the RF2 pin of the first single-pole double-throw switch S1; the VC2 pin of the third single-pole double-throw switch S3 is connected to the fourth control pin (pin 62) of the main control chip U1; and the RF1 pin of the third single-pole double-throw switch S3 is connected to… One end of the fifth inductor L5 is connected to one end of the ninth capacitor C9, and the other end of the fifth inductor L5 is connected to one end of the tenth capacitor C10 and the third antenna ANT3; the GND pin of the third single-pole double-throw switch S3, the other end of the ninth capacitor C9, and the other end of the tenth capacitor C10 are all grounded; the RF2 pin of the third single-pole double-throw switch S3 is connected to one end of the sixth inductor L6 and one end of the eleventh capacitor C11, and the other end of the sixth inductor L6 is connected to one end of the twelfth capacitor C12 and the fourth antenna ANT4, and the other ends of the eleventh capacitor C11 and the other ends of the twelfth capacitor C12 are all grounded.

[0043] The third single-pole double-throw switch S3 is preferably a high-frequency, low-loss SPDT (single-pole double-throw) switch of model TPUPG2179TB. The π-type matching formed by the fifth inductor L5, the ninth capacitor C9, and the tenth capacitor C10 is used for matching and debugging the third antenna ANT3. The π-type matching formed by L6, C11, and C12 is used for matching and debugging the fourth antenna ANT4. When the third control signal GPIO3 is active (low level) and the fourth control signal GPIO4 is inactive (high level), the RFC pin of S3 is connected to the RF1 pin, and the third antenna is connected. When the third control signal GPIO3 is inactive and the fourth control signal GPIO4 is active, the RFC pin of S3 is connected to the RF2 pin, and the fourth antenna is connected.

[0044] Preferably, the third switching module 33 further includes a seventh inductor L7, a thirteenth capacitor C13, and a fourteenth capacitor C14; one end of the seventh inductor L7 is connected to the RFC pin of the third single-pole double-throw switch S3 and one end of the fourteenth capacitor C14, and the other end of the seventh inductor L7 is connected to one end of the thirteenth capacitor C13 and the RF2 pin of the first single-pole double-throw switch S1. The other ends of the thirteenth capacitor C13 and the fourteenth capacitor C14 are both grounded. The π-type matching formed by L7, C13, and C14, combined with the π-type matching of L1, C1, and C2, is used to match the impedance across S1.

[0045] The truth table for the high and low levels of the four control signals and their connection to the antenna is shown in Table 1 below. In GPIO1 to GPIO4, 0 indicates a low level is active, and 1 indicates a high level is inactive. Since the antennas are all connected to their corresponding inductors, the connection to the overall circuit is selected by switching the corresponding single-pole double-throw switches. ANT_DIV1, ANT_DIV2, ANT_DIV3, and ANT_DIV4 represent the signals transmitted on the corresponding antennas; a value of 1 indicates signal transmission and the corresponding antenna is active; a " / " indicates no signal transmission and the corresponding antenna is inactive.

[0046]

[0047] Table 1

[0048] Please continue reading. Figures 1-3 The working principle of the antenna-switching camera is as follows:

[0049] By default, the first antenna ANT1 is operational. The first antenna signal ANT_DIV1 is converted into an ANT signal through S2 and S1 in sequence. The wireless chip U2 transmits the ANT signal to the main control chip U1. The main control chip U1 judges the signal strength of the current ANT signal. If it is greater than or equal to the threshold, no action is taken.

[0050] When a change in position causes the signal strength of the first antenna ANT1 to weaken below a threshold, the main control chip U1 first outputs four control signals in the combination 0110 (i.e., the first control signal GPIO1 is low, the second control signal GPIO2 is high, the third control signal GPIO3 is high, and the fourth control signal GPIO4 is low). At this time, the RFC pin of S1 is connected to the RF1 pin, and the RFC pin of S2 is connected to the RF2 pin, and the second antenna ANT2 is activated. The second antenna signal ANT_DIV2 is converted into an ANT signal through S2 and S1 in sequence, and transmitted to the main control chip U1 through the wireless chip U2. After receiving the current ANT signal, the main control chip U1 marks it, such as ANT2, to indicate its corresponding second antenna.

[0051] The main control chip U1 then outputs four control signals in combination 1001 (i.e., GPIO1 is high, GPIO2 is low, GPIO3 is low, and GPIO4 is high). At this time, the RFC pin of S1 is connected to the RF2 pin, and the RFC pin of S2 is connected to the RF1 pin, and the third antenna ANT3 is connected and activated. The third antenna signal ANT_DIV3 is converted into an ANT signal through S2 and S1 in sequence, and then transmitted to the main control chip U1 through the wireless chip U2. After receiving the current ANT signal, the main control chip U1 marks it, such as ANT3, to indicate that it corresponds to the third antenna.

[0052] The main control chip U1 then outputs four control signals in a 1010 combination (i.e., GPIO1 high, GPIO2 low, GPIO3 high, and GPIO4 low). At this time, the RFC pin of S1 is connected to the RF2 pin, and the RFC pin of S2 is also connected to the RF2 pin, thus activating the fourth antenna ANT4. The fourth antenna signal ANT_DIV4 is converted into an ANT signal sequentially through S2 and S1, and then transmitted to the main control chip U1 via the wireless chip U2. After receiving the current ANT signal, the main control chip U1 marks it, such as ANT4, to indicate that it corresponds to the fourth antenna.

[0053] The main control chip U1 compares the signal strengths of the three received ANT signals and determines the strongest signal strength. Assuming ANT3 has the strongest signal strength, it outputs four control signals in combination 1001, and the third antenna, ANT3, is connected and begins operation. The main control chip U1 controls each single-pole double-throw switch to poll and sequentially connect the corresponding antennas. Polling starts with the currently connected antenna and connects the antennas after it in sequence. The signal strength of each connected antenna is acquired, and the signal strengths of the remaining antennas are acquired and compared together to select the antenna with the best signal strength, ensuring that it always operates under the optimal signal strength.

[0054] In summary, the antenna redundancy circuit and its camera provided by this utility model can automatically poll and switch the connection status of each antenna according to the signal strength. Each time it switches, it obtains the signal strength of the currently connected antenna, compares the signal strength of each antenna, and connects the antenna with the strongest signal strength. This not only meets the data transmission requirements but also ensures that it operates under the optimal signal strength each time. The switching of multiple antennas solves the problem of communication obstruction caused by the dead angle of a single antenna.

[0055] The above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. An antenna redundancy circuit for antenna switching, disposed on a circuit board inside a camera housing, connecting a main control circuit, a wireless circuit, and several antennas on the circuit board, characterized in that, The antenna redundancy circuit includes a first switching module, a second switching module, and a third switching module; the first switching module is connected to the second switching module, the third switching module, and the wireless circuit; the first switching module, the second switching module, and the third switching module are all connected to the main control circuit. The first switching module switches the main antenna path according to the first control signal and the second control signal output by the main control circuit; The second switching module switches a portion of the antenna sub-paths according to the third and fourth control signals output by the main control circuit, and connects to the corresponding antenna; The third switching module switches another part of the antenna sub-paths according to the third control signal and the fourth control signal, and connects to the corresponding antenna.

2. The antenna redundancy circuit for antenna switching according to claim 1, characterized in that, The first switching module includes a first single-pole double-throw switch, a first inductor, a first capacitor, and a second capacitor; The VC1 pin of the first single-pole double-throw switch is connected to the main control circuit. The RFC pin of the first single-pole double-throw switch is connected to one end of the first inductor and one end of the second capacitor. The other end of the first inductor is connected to one end of the first capacitor and the wireless circuit. The VC2 pin of the first single-pole double-throw switch is connected to the main control circuit. The RF1 pin of the first single-pole double-throw switch is connected to the second switching module. The RF2 pin of the first single-pole double-throw switch is connected to the third switching module. The GND pin of the first single-pole double-throw switch, the other end of the first capacitor, and the other end of the second capacitor are all grounded.

3. The antenna redundancy circuit for antenna switching according to claim 2, characterized in that, The second switching module includes a second single-pole double-throw switch, a second inductor, a third inductor, a third capacitor, a fourth capacitor, a fifth capacitor, and a sixth capacitor; The VC1 pin of the second single-pole double-throw switch is connected to the main control circuit. The RFC pin of the second single-pole double-throw switch is connected to the RF1 pin of the first single-pole double-throw switch. The VC2 pin of the second single-pole double-throw switch is connected to the main control circuit. The RF1 pin of the second single-pole double-throw switch is connected to one end of the second inductor and one end of the third capacitor. The other end of the second inductor is connected to one end of the fourth capacitor and the first antenna. The GND pin of the second single-pole double-throw switch, the other end of the third capacitor, and the other end of the fourth capacitor are all grounded. The RF2 pin of the second single-pole double-throw switch is connected to one end of the third inductor and one end of the fifth capacitor. The other end of the third inductor is connected to one end of the sixth capacitor and the second antenna. The other ends of the fifth capacitor and the other ends of the sixth capacitor are all grounded.

4. The antenna redundancy circuit for antenna switching according to claim 3, characterized in that, The second switching module also includes a fourth inductor, a seventh capacitor, and an eighth capacitor; One end of the fourth inductor is connected to the RFC pin of the second single-pole double-throw switch and one end of the eighth capacitor. The other end of the fourth inductor is connected to one end of the seventh capacitor and the RF1 pin of the first single-pole double-throw switch. The other ends of the seventh capacitor and the eighth capacitor are both grounded.

5. The antenna redundancy circuit for antenna switching according to claim 2, characterized in that, The third switching module includes a third single-pole double-throw switch, a fifth inductor, a sixth inductor, a ninth capacitor, a tenth capacitor, an eleventh capacitor, and a twelfth capacitor. The VC1 pin of the third single-pole double-throw switch is connected to the main control circuit; the RFC pin of the third single-pole double-throw switch is connected to the RF2 pin of the first single-pole double-throw switch; the VC2 pin of the third single-pole double-throw switch is connected to the fourth control pin of the main control chip; the RF1 pin of the third single-pole double-throw switch is connected to one end of the fifth inductor and one end of the ninth capacitor; the other end of the fifth inductor is connected to one end of the tenth capacitor and the third antenna; the GND pin of the third single-pole double-throw switch, the other end of the ninth capacitor, and the other end of the tenth capacitor are all grounded; the RF2 pin of the third single-pole double-throw switch is connected to one end of the sixth inductor and one end of the eleventh capacitor; the other end of the sixth inductor is connected to one end of the twelfth capacitor and the fourth antenna; the other ends of the eleventh capacitor and the other ends of the twelfth capacitor are all grounded.

6. The antenna redundancy circuit for antenna switching according to claim 5, characterized in that, The third switching module also includes a seventh inductor, a thirteenth capacitor, and a fourteenth capacitor; One end of the seventh inductor is connected to the RFC pin of the third single-pole double-throw switch and one end of the fourteenth capacitor. The other end of the seventh inductor is connected to one end of the thirteenth capacitor and the RF2 pin of the first single-pole double-throw switch. The other ends of the thirteenth capacitor and the fourteenth capacitor are both grounded.

7. A camera with antenna switching capability, comprising a housing, wherein a circuit board is disposed within the housing, and the circuit board integrates a main control circuit and a wireless circuit, characterized in that, The housing also contains several antennas located at preset positions, and the circuit board integrates an antenna redundancy circuit as described in any one of claims 1-6; the main control circuit is connected to the wireless circuit and the antenna redundancy circuit, and the antenna redundancy circuit is connected to the wireless circuit and several antennas; The wireless circuit obtains the signal strength of the currently connected antenna through the current connection status of the antenna redundancy circuit and transmits it to the main control circuit. When the main control circuit determines that the signal strength is lower than the threshold, it controls the antenna redundancy circuit to poll and switch the connection status of each antenna. Each time the connection is switched, the wireless circuit acquires the signal strength of the currently connected antenna and transmits it to the main control circuit. The main control circuit compares the signal strength of each antenna and controls the antenna redundancy circuit to connect the corresponding antenna based on the strongest signal strength.

8. The camera with antenna switching according to claim 7, characterized in that, The main control circuit includes a main control chip, and the wireless circuit includes a wireless chip; the four control pins of the main control chip are connected to the antenna redundancy circuit, the communication pin of the main control chip is connected to the data pin of the wireless chip, and the antenna pin of the wireless chip is connected to the antenna redundancy circuit.

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