Reinforced industrial tablet wireless communication anti-interference method, circuit and system

Abstract

The application relates to the technical field of wireless communication, in particular to a reinforced industrial tablet computer wireless communication anti-interference method, circuit and system. The steps comprise: performing frequency band specificity filtering and impedance matching on RF_WBT Bluetooth signals and RF_WF_5G wireless signals through a multistage filtering network, the application performs frequency band specificity processing on Bluetooth and 5G Wi-Fi signals through the multistage filtering network, effectively eliminates crosstalk between different frequency band signals and improves signal purity, and reduces the influence of cross-frequency band interference from the front-end radio frequency link layer; the gain, phase and timing interaction of the multi-mode signal are dynamically calibrated through an anti-interference algorithm integrated with a control chip, the channel competition and phase noise problems during parallel transmission of the multi-mode signal are solved through time division multiplexing mechanism and phase synchronization calibration, and the collaborative optimization of multiple communication modules is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wireless communication, in particular to a reinforced industrial tablet computer wireless communication anti-interference method, circuit and system. BACKGROUND

[0002] As an interactive terminal of industrial control and intelligent equipment, the wireless communication performance of the reinforced industrial tablet computer directly affects the interaction result. However, there are multiple challenges in the complex industrial environment, such as multi-band electromagnetic signal coupling, multi-mode communication module parallel interference, power supply noise conduction, etc. The traditional wireless communication anti-interference scheme is usually designed for a single frequency band or a single type of interference, and it is difficult to effectively handle the cross crosstalk of 2.4GHz and 5GHz frequency band signals, the channel competition when Wi-Fi and Bluetooth and other multi-mode signals are concurrent, and the conduction interference of high-frequency noise on the power supply end to the radio frequency link. Especially when the device is in a strong electromagnetic interference area, the existing scheme has deficiencies in the timing calibration accuracy of multi-mode signal cooperative processing, the power supply fluctuation suppression capability and the adaptive adjustment strategy in complex scenarios, resulting in increased signal transmission loss, increased bit error rate and even communication link interruption, which cannot meet the stability requirements of industrial-grade devices for wireless communication. The technical problem thus raised is: how to construct a scheme that integrates multi-band filtering, multi-mode cooperative control, power supply noise isolation and adaptive interference suppression to improve the reliability of the wireless communication of the reinforced industrial tablet computer. SUMMARY

[0003] The present disclosure proposes a reinforced industrial tablet computer wireless communication anti-interference method, circuit and system, aiming to overcome at least one of the deficiencies in the prior art.

[0004] To achieve the above-mentioned purpose, the technical scheme disclosed by the present application is as follows:

[0005] According to one aspect of the present disclosure, a reinforced industrial tablet computer wireless communication anti-interference method is provided, comprising the steps of:

[0006] RF_WBT Bluetooth signals and RF_WF_5G wireless signals are subjected to frequency-specific filtering and impedance matching through a multi-stage filtering network, which includes an RF_WBT signal filtering branch composed of L1010 inductance and C1009 capacitance, an RF_WF_5G signal first filtering branch composed of L1008 inductance and C1006 capacitance, and an RF_WF_5G signal second filtering branch composed of L1007 inductance and C1006 capacitance, for eliminating frequency crosstalk and improving signal purity;

[0007] The Wi-Fi, Bluetooth, GPS and FM signals are processed synchronously through the control chip U1002, the gain and phase of the signal link are dynamically calibrated by using an anti-interference algorithm based on signal strength threshold to adjust the data interface interaction timing of the Bluetooth and Wi-Fi signals, so as to avoid parallel interference of multi-mode signals.

[0008] The circuit is powered through the VCN28_PMU power supply port, and a decoupling capacitor is configured at the AVDD33_WB and AVDD18_WB power supply nodes, which is used for filtering high-frequency noise of the power supply end, stabilizing voltage output and reducing the influence of power supply fluctuation on radio frequency processing.

[0009] The signal strength of the WBG_ANT and FM_ANT antenna interfaces is monitored in real time, when the frequency band interference exceeds the threshold, the gain mode of the U1004 amplifier in the GPS signal link is dynamically switched through the GPIO_GPS_LNA_EN port, and the GPS signal filtering parameters of the Elec_cn interface are adjusted, which is used for stable signal reception in complex environment.

[0010] Further, the first filter branch performs band-pass filtering on the RF_WBT signal through an LC series network composed of an L1010 inductor and a C1009 capacitor to filter out stray signals outside the 2.4GHz frequency band; the second filter branch and the third filter branch are cascaded to form a π-type filter network, wherein an L1008 inductor and a C1006 capacitor constitute a high-frequency pre-filter unit, and an L1007 inductor and a C1006 capacitor constitute a secondary filter unit, which together perform noise suppression and impedance matching on the RF_WF_5G signal in the 5GHz frequency band to ensure that the signal transmission loss is lower than a preset threshold.

[0011] Further, the steps of the anti-interference algorithm include:

[0012] The error rate data of the Bluetooth signal is collected in real time through the CONN_BT_DATA and CONN_BT_CLK interfaces, and the throughput parameters of the Wi-Fi signal are obtained through the CONN_WF_CTRL0 / 1 / 2 interfaces;

[0013] When it is detected that the error rate of the Bluetooth signal exceeds a first preset percentage and the Wi-Fi throughput decreases by a second preset percentage, a time division multiplexing mechanism is triggered, and the channel occupation time of the Bluetooth and Wi-Fi signals is staggered by 50μs by adjusting the internal timer of the control chip U1002.

[0014] The phase synchronization calibration is performed on the quadrature baseband data of the Bluetooth and Wi-Fi signals through the BT_QP / QN and WF_QP / QN interfaces to eliminate the phase noise interference of signals in the same frequency band and avoid channel competition when multi-mode signals are concurrently transmitted.

[0015] Further, the configuration method of the decoupling capacitor includes: connecting a 100nF C1017 capacitor and a 100pF C1011 capacitor in parallel at the AVDD33_WB power port, respectively used to filter low-frequency noise below 100kHz and high-frequency noise above 10MHz; connecting a 10nH L1001 inductor and a 22μF C1020 capacitor in series at the VCN28_PMU power inlet to form an LC filter circuit, used to suppress the surge noise of the power input end, so as to ensure that the power supply voltage fluctuation range of the control chip U1002 does not exceed ±1%.

[0016] Further, the detection step of the frequency band interference includes: real-time acquisition of the FM signal amplitude through the voltage division network composed of the R1006 resistor and the L1008 inductor of the FM_ANT interface, and when the amplitude is lower than 50mV, it is determined as a strong interference environment; by adjusting the filter parameters of the C1016 capacitor and the L1005 inductor in the GPS signal processing link, the passband bandwidth of the GPS signal is reduced from 20MHz to 10MHz, and the low-noise amplification mode of the U1004 amplifier is activated, and the signal gain is increased by 15dB.

[0017] According to another aspect of the present disclosure, a wireless communication circuit is provided for implementing the ruggedized industrial tablet computer wireless communication anti-interference method as described above, comprising:

[0018] An RF signal processing unit for filtering and matching RF_WBT and RF_WF_5G signals, the RF signal processing unit comprising inductors L1010, L1008, L1007 and capacitors C1009, C1006;

[0019] An antenna interface unit for receiving and transmitting Wi-Fi and Bluetooth signals, the antenna interface unit comprising a WBG_ANT interface and an AVDD33_WB power port;

[0020] An FM receiving unit for receiving and processing FM signals, the FM receiving unit comprising an FM_ANT interface, resistors R1006 and R1005, and an inductor L1008;

[0021] A GPS signal processing unit for receiving and processing GPS signals, the GPS signal processing unit comprising an Elec_cn interface, an inductor L1005, a capacitor C1016, and an amplifier U1004;

[0022] A power management unit for providing stable power supply for the entire module, the power management unit comprising a VCN28_PMU power port and a plurality of capacitors;

[0023] A control chip U1002 is used for processing Wi-Fi, Bluetooth, GPS and FM signals, and interacting with external devices through multiple pins, and the control chip U1002 has multiple power supply ports and data interfaces.

[0024] Further, the RF signal processing unit further comprises:

[0025] A first filter network comprising inductance L1010, capacitance C1009 and resistance 50Ω is used for filtering and matching RF_WBT signals;

[0026] A second filter network comprising inductance L1008, capacitance C1006 and resistance 50Ω is used for filtering and matching RF_WF_5G signals;

[0027] A third filter network comprising inductance L1007, capacitance C1006 and resistance 50Ω is also used for filtering and matching RF_WF_5G signals.

[0028] Further, the antenna interface unit further comprises:

[0029] Capacitances C1005 and C1007 are connected on both sides of the WBG ANT interface for filtering;

[0030] Capacitances C1017 and C1015 are connected on the AVDD33_WB power supply port for power filtering;

[0031] The FM receiving unit further comprises:

[0032] Inductance L1008 and resistance R1004 are used for impedance matching and filtering of FM signals;

[0033] Capacitance C1019 and resistance R1005 are used for coupling and filtering of FM signals.

[0034] Further, the GPS signal processing unit further comprises:

[0035] Inductance L1005 and capacitance C1016 are used for filtering of GPS signals;

[0036] Amplifier U1004 has input end IN_GND, output end RFOUT and reference voltage end VCC, and is used for amplifying and processing filtered GPS signals;

[0037] Capacitance C1018 and inductance L1001 are used for filtering and matching of GPS signals.

[0038] According to another aspect of the present disclosure, a ruggedized industrial tablet wireless communication anti-interference system is provided, integrated with the wireless communication circuit as described above, comprising:

[0039] A multi-band signal processing module is configured to perform multi-band filtering and matching of signals, including an RF_WBT signal filtering branch, an RF_WF_5G signal multi-stage filtering network, and corresponding inductors L1010 / L1008 / L1007 and capacitors C1009 / C1006, to achieve independent filtering and impedance matching of signals of different frequency bands.

[0040] A multi-mode cooperative control module includes a control chip U1002 and its configured CONN_BT_DATA / CLK, CONN_WF_CTRL0 / 1 / 2 data interfaces, for performing multi-mode signal cooperative processing, and dynamically adjusting the interaction timing and phase calibration parameters of multi-mode signals through a preset anti-interference algorithm.

[0041] A power supply noise isolation module includes a VCN28_PMU power supply port, AVDD33_WB / 18_WB power supply nodes, and decoupling capacitors C1017 / C1015 / C1020, for filtering and stabilizing power supply noise.

[0042] An anti-interference strategy adaptive module includes a signal monitoring circuit of the WBG_ANT / FM_ANT antenna interface, a GPIO_GPS_LNA_EN port, and a U1004 amplifier control unit, for real-time monitoring of signal strength and dynamic adjustment of filtering parameters and amplification gain.

[0043] A storage unit is configured to store preset anti-interference algorithm parameters, signal threshold configurations, and dynamic adjustment strategies, to support real-time calling of the control chip U1002.

[0044] A clock synchronization unit is configured to provide high-precision clock signals to ensure nanosecond-level timing calibration accuracy of Bluetooth and Wi-Fi signals, and is electrically connected to the multi-band signal processing module and the multi-mode cooperative control module to implement the steps of the ruggedized industrial tablet wireless communication anti-interference method.

[0045] The present application has the following advantages:

[0046] The application effectively eliminates the crosstalk between signals of different frequency bands and improves the signal purity by constructing a multi-stage filtering network to perform frequency band-specific processing on Bluetooth and 5G Wi-Fi signals, thereby reducing the cross-frequency interference from the front-end radio frequency link level; the gain, phase and timing interaction of the multi-mode signal are dynamically calibrated by using the anti-interference algorithm integrated in the control chip, and the channel competition and phase noise problems during the parallel transmission of the multi-mode signal are solved through time division multiplexing mechanism and phase synchronization calibration, thereby realizing the collaborative optimization of multiple communication modules; a multi-stage power noise isolation system is constructed through the configuration of power node decoupling capacitor and the design of LC filter circuit, thereby suppressing the high-frequency noise and surge interference at the power end and ensuring the stability of the power supply of the core circuit; the signal amplification gain mode is dynamically switched and the filtering parameters are optimized by combining real-time signal strength monitoring and adaptive adjustment strategy, thereby significantly improving the signal reception capability in complex electromagnetic environment.

[0047] Further, the multi-layer anti-interference system from the radio frequency front end to the baseband processing and from the hardware filtering to the software algorithm cooperatively solves the problems of multi-frequency crosstalk, multi-mode signal conflict, power noise coupling and insufficient environmental adaptability in industrial scenarios, thereby effectively reducing the transmission loss of wireless communication signals, significantly controlling the bit error rate and comprehensively improving the stability of the communication link, and providing a systematic solution for reinforcing the reliable operation of industrial tablet computers in strong interference environment.

[0048] The above description is only a summary of the technical solutions of the application, in order to more clearly understand the technical means of the application and can be implemented according to the content of the description, the following is a preferred embodiment of the application and the detailed description is combined with the drawings. BRIEF DESCRIPTION OF DRAWINGS

[0049] Figure 1 The flowchart of the wireless communication anti-interference method in an embodiment of the application is shown in the figure.

[0050] Figure 2 The wireless communication circuit topology diagram in an embodiment of the application is shown in the figure.

[0051] Figure 3 The frequency band-specific filtering response characteristic diagram in an embodiment of the application is shown in the figure.

[0052] Figure 4 The time division multiplexing timing diagram of multi-mode signal in an embodiment of the application is shown in the figure.

[0053] Figure 5 The noise power spectral density comparison diagram before and after phase synchronization calibration in an embodiment of the application is shown in the figure.

[0054] Figure 6 The power noise spectrum suppression effect diagram in an embodiment of the application is shown in the figure.

[0055] Figure 7A dynamic gain adaptive control response schematic diagram in an embodiment of the present application;

[0056] Figure 8 A GPS signal strength change schematic diagram under adaptive gain adjustment in an embodiment of the present application;

[0057] Figure 9 A band-pass filter parameter optimization analysis schematic diagram in an embodiment of the present application;

[0058] Figure 10 A multi-mode signal bit error rate comparison schematic diagram in an embodiment of the present application;

[0059] Figure 11 A GPS filter bandwidth adjustment effect schematic diagram in an embodiment of the present application;

[0060] Figure 12 A time division multiplexing channel occupation timing schematic diagram in an embodiment of the present application;

[0061] Figure 13 A complex environment communication throughput schematic diagram in an embodiment of the present application. DETAILED DESCRIPTION

[0062] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application.

[0063] The present application provides the following preferred embodiments:

[0064] Embodiment one: in order to solve the signal crosstalk, multi-mode concurrent conflict and power noise conduction problems caused by wireless communication frequency band interference in industrial environment, the present embodiment discloses a multi-stage isolation filtering and dynamic cooperative control communication anti-interference method, which realizes the stability optimization of signal link through fine filtering architecture and real-time gain control. As shown in the figure, the flow of the anti-interference method is as follows: Figure 1

[0065] S100: through the multi-stage filtering network, the RF_WBT Bluetooth signal and the RF_WF_5G wireless signal are subjected to frequency band specificity filtering and impedance matching, the multi-stage filtering network includes the RF_WBT signal filtering branch composed of L1010 inductor and C1009 capacitor, the RF_WF_5G signal first filtering branch composed of L1008 inductor and C1006 capacitor and the RF_WF_5G signal second filtering branch composed of L1007 inductor and C1006 capacitor, which is used to eliminate frequency band crosstalk and improve signal purity;

[0066] ​S200: synchronously process Wi-Fi, Bluetooth, GPS and FM signals by controlling chip U1002, dynamically calibrate the gain and phase of the signal link by using an anti-interference algorithm that adjusts the data interface interaction timing of Bluetooth and Wi-Fi signals based on signal strength threshold, to avoid multi-mode signal parallel interference;

[0067] S300: power the circuit through the VCN28_PMU power supply port, and configure decoupling capacitors at the AVDD33_WB and AVDD18_WB power supply nodes, to filter high-frequency noise from the power supply end and stabilize voltage output and reduce the impact of power supply fluctuations on radio frequency processing;

[0068] S400: real-time monitor the signal strength of the WBG_ANT and FM_ANT antenna interfaces, when the frequency band interference exceeds the threshold, dynamically switch the gain mode of the U1004 amplifier in the GPS signal link through the GPIO_GPS_LNA_EN port, and adjust the GPS signal filtering parameters of the Elec_cn interface, for stable signal reception in complex environments.

[0069] Specifically, the coexisting Bluetooth (RF_WBT) and 5G Wi-Fi (RF_WF_5G) signals are physically isolated by an inductor-capacitor composite topology. Among them, the π-type resonance branch composed of inductor L1010 and capacitor C1009 takes 2.4GHz as the center frequency, suppresses the out-of-band stray signals through the fourth-order Butterworth response function, and its transmission characteristic presents steep out-of-band roll-off, as shown by the blue curve in the accompanying Figure 3 The RF_WF_5G channel adopts a double-branch collaborative design: the first branch forms a 5.6GHz main resonance point by L1008 and C1006, and the second branch compensates for the 4.9GHz frequency point by L1007 and C1006. After the two branches are connected in parallel, they cover the 5GHz frequency band double-peak characteristic, as shown by the green curve in the accompanying Figure 3 It should be understood that this structure reduces the insertion loss to below 0.8dB through the impedance matching network, while ensuring that the group delay error of each branch is less than 3ns, thereby eliminating the intermodulation interference caused by frequency band overlap.

[0070] Further, the control chip U1002 dynamically allocates its time slot resources to avoid concurrent conflicts by monitoring the Wi-Fi / Bluetooth signal strength threshold. Specifically, when the Bluetooth signal strength exceeds -82dBm, a time division multiplexing mechanism based on a time window is triggered: the Bluetooth data frame transmission period is accurately embedded in the Wi-Fi beacon interval, as shown by the accompanying Figure 12As shown: the original uncalibrated signal (red) overlaps with the Wi-Fi channel (blue), and after calibration (green), time slot avoidance is achieved. Further, the chip synchronously regulates the gain phase of GPS and FM signals: using a phase-locked loop to compensate for the local oscillator frequency offset of the receiving link, the phase noise variance of multi-mode signals is reduced by 45% when sharing the radio frequency front end.

[0071] Further, for the fluctuation interference of AVDD33_WB and AVDD18_WB power supply nodes, a three-stage decoupling strategy is deployed at the VCN28_PMU power supply port: the first stage filters out low-frequency ripples below 100 kHz by a 100 μF tantalum capacitor; the second stage absorbs medium-frequency noise below 10 MHz by a 0.1 μF ceramic capacitor; and the third stage suppresses GHz-level high-frequency switching noise by a distributed 1nF capacitor array, as shown in the accompanying Figure 5 As shown, the power supply noise power spectral density decreases by 12 dB in the 1-100 MHz frequency band. It can be understood that the design improves the power supply rejection ratio (PSRR) to -68 dB@1 MHz, ensuring that the bias voltage fluctuation of the radio frequency amplifier does not exceed ±1.5%.

[0072] Further, the working mode of the U1004 amplifier is controlled through the GPIO_GPS_LNA_EN port: when the WBG_ANT antenna interface detects in-band blocking interference >-95 dBm, it switches to a high linearity mode, with a gain reduction of 8 dB but an IP3 improvement of +15 dBm; at the same time, the parameters of the digital control filter connected by the Elec_cn interface are adjusted, compressing the GPS L1 frequency band bandwidth from 20 MHz to 10 MHz, as shown in the accompanying Figure 11 As shown, the out-of-band noise is suppressed by >14 dB in narrowband mode, which improves the signal-to-noise ratio margin while maintaining the gain of the 1.575 GHz center frequency.

[0073] The benefits of this embodiment are: through the four-dimensional collaborative mechanism of frequency domain physical isolation, time domain peak avoidance transmission, power supply noise layered suppression, gain adaptive adjustment filter branch, time division multiplexing, three-stage decoupling and mode switching, a full-stack anti-interference system from the physical layer to the protocol layer is constructed, and the anti-interference performance of multi-mode wireless communication is significantly enhanced without adding additional hardware resources.

[0074] Embodiment Two: To solve the frequency band crosstalk problem of 2.4 GHz Bluetooth and 5 GHz Wi-Fi signals in industrial environments, this embodiment refines the structure of the multi-stage filter network. Specifically, the first filter branch consists of an inductor L1010 and a capacitor C1009 in a series LC resonant network, as shown in the accompanying Figure 2 As shown, the center frequency is configured as 2.4 GHz. This network forms a narrowband pass response in the frequency domain by adjusting the resonance point of the inductor and the capacitor, as shown in the accompanying Figure 3As shown in the middle blue curve, the passband range of the RF_WBT Bluetooth signal is limited within 2.4 GHz ± 50 MHz, and the out-of-band attenuation is greater than or equal to 40 dB. Among them, the value of the inductor L1010 needs to satisfy the equivalent cancellation of the inductive reactance and the capacitive reactance at the target frequency point, so as to maximize the signal transmission efficiency; at the same time, the selection of the capacitance value of the capacitor C1009 needs to take into account the influence of high-frequency parasitic parameters, to avoid the deterioration of the passband edge roll-off characteristic caused by the decrease of Q value, such as Figure 9

[0075] Further, for the 5GHz Wi-Fi signal (RF_WF_5G), the embodiment adopts a two-stage cascaded π-type filter network, and the bandpass response thereof is shown in the green curve as follows: Figure 3

[0076] The high-frequency pre-filtering unit is composed of an inductor L1008 and a capacitor C1006, wherein the inductance value of the inductor L1008 is set to be less than 1 / 4 of that of the low-frequency unit, so as to reduce the high-frequency inductive loss; the capacitor C1006 is a low-ESR ceramic capacitor, and the self-resonance frequency thereof needs to cover the 5GHz frequency band. The unit performs first attenuation on stray signals outside the 4.5GHz-5.8GHz range, as shown in the middle 5.5GHz left side attenuation band, while providing impedance buffering for the subsequent stage. Figure 3

[0077] The secondary filtering unit is composed of an inductor L1007 and a capacitor C1006, and the topology thereof is mirror-symmetrical to that of the pre-filtering unit. The inductance value of the inductor L1007 is further reduced, and by adjusting the secondary resonance point thereof and the capacitor C1006, the passband is compressed to the range of 5.1GHz-5.7GHz, as shown in the middle 5GHz main peak area. Figure 3 Figure 3 The fluctuation amplitude of the green curve is less than or equal to 0.5dB.

[0078] Further, the two units form an impedance gradual change structure after being cascaded, which gradually transitions from 50Ω input to 75Ω output at the RF chip end. This design controls the overall signal loss to be less than or equal to 1.2dB while matching the impedance of the transmission line, so as to meet the preset threshold. It should be understood that the capacitor C1006 in the π-type network serves as a shared element, which participates in the parallel resonance of the pre-filtering unit and forms a series ground path of the secondary filtering unit. This design reduces the number of discrete components and reduces the parasitic inductance effect.

[0079] Further, in combination with Figure 6 ​​​​As shown in the power supply noise suppression diagram, the performance of the high-frequency filter unit is easily affected by power supply noise. Therefore, in this embodiment, 100nF and 100pF capacitors are connected in parallel at the AVDD33_WB power node to shunt low-frequency switching noise (<100kHz) and high-frequency coupling noise (>10MHz), respectively, ensuring that the inductor components of the π-type network are not modulated by power supply ripple. In addition, the package selection of inductor L1007 needs to meet the skin effect requirements of the 5GHz band, and its copper wire diameter and winding spacing are optimized for high frequency to reduce eddy current losses.

[0080] The advantage of this embodiment is that, through the collaborative design of the LC series network and the π-type cascaded network, differentiated filtering responses are provided for the frequency band characteristics of Bluetooth and Wi-Fi signals, respectively. Figure 3 The bimodal characteristics. This structure achieves improved channel isolation on space-constrained industrial panel PC circuit boards, such as... Figure 10 The separation phenomenon of the bit error rate comparison curve and such Figure 11 The insertion loss is optimized to improve the signal-to-noise ratio after mid-bandwidth adjustment, while avoiding the group delay distortion problem introduced by traditional broadband filters.

[0081] Example 3: To address the channel conflict issue during concurrent transmission of Bluetooth and Wi-Fi signals in industrial environments, this example refines the dynamic time-division multiplexing control method based on hardware interface monitoring. Specifically, real-time sampling of the Bluetooth bit error rate is achieved through the collaborative use of the CONN_BT_DATA and CONN_BT_CLK dual interfaces: CONN_BT_DATA captures the parity bit error status of data packets, and CONN_BT_CLK synchronously extracts clock jitter parameters. These two parameters are then fused and calculated by the coprocessor of the control chip U1002 to generate a dynamic bit error rate index with a period of 1ms. Simultaneously, Wi-Fi throughput parameters are obtained through the CONN_WF_CTRL0 / 1 / 2 tri-state interface: CTRL0 monitors the MAC layer data frame retransmission rate, CTRL1 detects the physical layer subcarrier modulation efficiency, and CTRL2 tracks the transmit buffer queue depth. The three parameters are weighted and combined to obtain the throughput degradation coefficient.

[0082] Furthermore, the system sets a two-level correlation judgment threshold: when the Bluetooth bit error rate index exceeds the first preset percentage (typical value 5%) for three consecutive cycles and the Wi-Fi throughput degradation coefficient decreases simultaneously by the second preset percentage (typical value 15%), the time-division multiplexing hardware reconfiguration mechanism is triggered. At this time, the internal timer of the control chip U1002 performs dynamic time slot division: based on the baseband clock source, a phase offset with a precision of 50μs is generated, and the channel access window of the Bluetooth signal is fixedly delayed by 50μs, such as... Figure 4The diagram illustrates the time slot staggering effect between the Wi-Fi and Bluetooth pulses. This operation is achieved by modifying the timer's compare-match register, ensuring strict time-domain isolation between the Bluetooth TX / RX enable signal and the Wi-Fi transceiver window. Figure 12 The timing diagram below shows the distribution of non-overlapping signal strength.

[0083] It is important to emphasize that time-division multiplexing only resolves channel occupancy conflicts, while co-band phase noise interference needs to be eliminated through baseband layer collaborative calibration. Therefore, this embodiment designs an orthogonal signal phase synchronization link:

[0084] The Bluetooth baseband data stream is input to the programmable phase shifter via the BT_QP / QN differential interface, and its I / Q channels are mixed with the local oscillator respectively;

[0085] The Wi-Fi baseband data stream is connected to the same source oscillator via the WF_QP / QN interface, but a digitally controlled attenuator is inserted to compensate for the path delay;

[0086] The two signals undergo cross-correlation calculations within the control chip. When a phase deviation > 0.1 radians is detected, such as... Figure 5 Before calibration, the peak of the phase noise spectrum is detected, and the rotation angle of the phase shifter and the compensation value of the attenuator are automatically adjusted until the full width at half maximum (FWHM) of the cross-correlation peak is compressed by 40%. Figure 5 Flattening characteristics of the calibrated curve.

[0087] The advantage of this embodiment is that, through a dual-mode collaborative sensing mechanism, multi-interface data fusion judgment is used to avoid false triggering by a single signal indicator, such as... Figure 10 The bit error rate comparison curve is shown in the figure. Through hardware-level time isolation, a fixed offset of 50μs balances scheduling efficiency and clock accuracy, as shown in the figure. Figure 4 and Figure 12 The timing non-overlapping characteristics. Through joint phase noise suppression, the closed-loop calibration of the orthogonal interfaces BT_QP / QN and WF_QP / QN eliminates in-band intermodulation distortion, such as... Figure 5 The mid-phase noise power spectral density decreases. This design, while maintaining throughput stability, exhibits a gradual decay of the adaptive anti-interference curve when the interference index > 5, such as… Figure 13 As shown, this reduces the bit error rate of multi-mode concurrent communication by half an order of magnitude, such as... Figure 10 The green curve shows a step improvement at SNR=4.2dB.

[0088] Example 4: To address the common-mode interference problem of power supply noise on wireless communication modules in industrial environments, this example refines the hardware implementation structure of the power supply filtering network. By deploying differentiated capacitor combinations and LC filter topologies at key power supply nodes of the control chip U1002, a multi-band noise suppression system is formed.

[0089] Specifically, a 100 nF ceramic capacitor C1017 and a 100 pF gallium nitride capacitor C1011 are arranged in parallel at the chip radio frequency unit power supply pin AVDD33_WB: the equivalent series inductance of C1017 is less than 0.5 nH, mainly for absorbing low-frequency ripples below 100 kHz; and C1011 adopts a low-loss dielectric material with a dielectric constant temperature coefficient of less than ± 30 ppm / °C, which can effectively suppress switching noise above 10 MHz. The physical layout of the two is radially symmetrically arranged within 1.5 mm of the power supply pin, forming a distributed decoupling path, such as Figure 6 The frequency division segment attenuation characteristics of the green and red curves.

[0090] Further, a second-order LC filter circuit is constructed at the direct current power input port VCN28_PMU: a 10 nH sandwich structure ferrite inductor L1001 is connected in series to the power supply main line, with a direct current impedance of less than 5 mΩ and a saturation current of 8 A; and a 22 μF tantalum polymer capacitor C1020 has an equivalent series resistance of 150 mΩ and an operating temperature range of -55°C to 125°C. This combination limits the input surge voltage peak to within ± 200 mV through the double mechanisms of inductance magnetic flux mutation suppression and capacitance charge buffering. It can be understood that the inductance value of L1001 takes into account the impedance matching characteristics of the switching power supply base frequency (typical value 500 kHz) and high-frequency harmonics (above 3 MHz), such as Figure 6 Indicated in the medium and high frequency switching noise area.

[0091] It needs to be explained that the power integrity design needs to meet multi-dimensional constraints:

[0092] Thermal stability coupling, the negative temperature coefficient characteristics of C1011 compensate for the medium loss warming effect of C1017, so that the impedance fluctuation within 1 MHz to 50 MHz is less than ± 3%;

[0093] Electromagnetic compatibility coordination, the magnetic shielding shell of L1001 and the PCB ground layer form a Faraday cage structure to block the spatial coupling of power supply noise to the RF front end;

[0094] Dynamic response optimization, the fast charge and discharge rate (<10 μs recovery time) of C1020 ensures that the instantaneous voltage drop under sudden load fluctuation does not exceed ± 1%, such as Figure 6 The smooth transition characteristics of the filtered noise curve under step disturbance.

[0095] The benefits of this embodiment are: covering low-frequency power frequency interference (100 Hz-100 kHz) and high-frequency switching noise (2 MHz-100 MHz) at the same time through the frequency division decoupling strategy; the 36 dB / octave roll-off characteristic of the LC filter topology reduces the power supply noise floor to below 150 μV / √Hz, such as Figure 6The self-healing property of the tantalum polymer capacitor improves the long-term reliability at extreme temperatures, and stabilizes the peak-to-peak voltage fluctuation within ±1% of the rated value.

[0096] Embodiment Five: In order to solve the problem of communication stability caused by mutual interference of multi-band wireless signals in complex industrial environments, this embodiment further refines the dynamic detection of frequency band interference and the adaptive adjustment mechanism of link parameters. By constructing a specific signal collection network and hardware parameter adjustment link, autonomous response in strong interference environment is realized to ensure effective reception of key wireless signals.

[0097] In the FM frequency band interference detection link, this embodiment uses a voltage division network composed of R1006 precision resistor and L1008 high-frequency inductor to collect the signal amplitude of FM ANT interface in real time. The impedance matching design of this voltage division network meets the 50Ω system characteristics, the resistance value of R1006 is selected as 120Ω to adapt to the high-frequency characteristics of the front-end antenna, and the inductance of L1008 is 10nH to effectively suppress the influence of direct current bias on alternating current signal collection. When the FM signal amplitude is detected to be lower than 50mV, it is determined that the current environment is in strong interference——the setting of this threshold is based on the energy distribution characteristics of typical electromagnetic noise in industrial scenes, and a lower amplitude indicates that there is wideband noise or strong interference signal in the same frequency band that suppresses the useful signal, such as Figure 5 the abnormal lifting feature of the mid-noise power spectral density curve.

[0098] Further, for the GPS signal receiving link, this embodiment adjusts the combined parameters of C1016 patch capacitor and L1005 wire inductance to realize the dynamic shrinkage of passband bandwidth. Among them, C1016 uses an adjustable capacitor array, which is initially configured as 22pF to realize a 20MHz passband width, and its capacitance value is increased to 47pF through I2C interface control after strong interference is triggered, and the LC filter network is reconstituted with the fixed value of L1005 (47nH), which is calculated to reduce the passband bandwidth to 10MHz, as shown in Figure 11 the measured curve of horizontal bandwidth parameter adjustment. This adjustment effectively filters out out-of-band noise outside the passband and reduces the influence of adjacent channel interference on GPS signals, as shown in Figure 8 At the same time, the signal amplification module U1004 enters the low-noise amplification mode, and the two-stage amplification circuit integrated inside it increases the signal gain from the default 10dB to 25dB by switching the bias resistor network, and the actual effective gain increase is 15dB. This mode is realized through hardware register configuration, and the response time is less than 1μs, ensuring that the signal link is quickly switched from the low-gain wide-frequency mode to the high-gain narrow-band mode, as shown in Figure 7 the mutation characteristics of the gain adaptive adjustment curve in the strong interference region.

[0099] It needs to be understood that the above adjustment process is automatically executed by the GPIO interface of the core control chip U1002 without external intervention. The control logic is realized by an internal state machine: after the detection module outputs the interference judgment signal, the GPIO port sends the capacitor array configuration instruction and the amplifier mode switching instruction in turn, and the response state of each hardware unit is fed back to the control chip in real time through the feedback pin, forming a closed loop control, like Figure 4 and Figure 12 the similar interaction mechanism of time division multiplexing timing control logic. This fully autonomous adjustment strategy avoids the lag of manual intervention and is especially suitable for unattended industrial site environment.

[0100] It can be understood that the synergistic effect of filter parameter adjustment and amplifier mode switching is essentially a dynamic optimization between signal bandwidth and noise suppression: narrowing the bandwidth can limit the instantaneous dynamic range of the signal, but can effectively improve the in-band signal-to-noise ratio; increasing the gain compensates for the signal attenuation that may be introduced in the filtering process, ensuring that the signal power received by the backend baseband processing unit is maintained within a reasonable range, such as Figure 9 the correlation between signal-to-noise ratio and bandwidth shown in the bandpass filter parameter optimization analysis. This dual-mechanism adjustment strategy has universality in industrial electromagnetic environment and is suitable for both fixed frequency band continuous interference scenarios and sudden pulse interference impacts.

[0101] This embodiment constructs a real-time interference detection mechanism based on a voltage division network, determines the interference level by a clear amplitude threshold, and provides a reliable basis for subsequent parameter adjustment; it realizes the coordinated adjustment of the bandwidth and gain of the GPS signal link, forming a double protection against interference at the hardware level; the full automation design of the control process improves the autonomous response capability of the system, which matches the rugged design requirements of the industrial tablet computer, and ensures the continuous and stable operation of the communication link in a strong interference environment.

[0102] This embodiment realizes the full-process autonomous processing from interference detection to link optimization without relying on external control, effectively improving the performance of the wireless communication module in complex electromagnetic environment, and the combination of its hardware adjustment mechanism and control logic provides a replicable engineering implementation path for the anti-interference design of industrial-grade devices.

[0103] Embodiment Six: To solve the interference coupling problem of multiple wireless signal coexistence in complex industrial environment, this embodiment further provides an architecture design of a wireless communication circuit, which realizes the physical carrier construction of the anti-interference method through the collaborative configuration of each functional unit. The circuit architecture follows the principle of modular design to ensure independent processing and system-level collaborative control of different frequency band signals, providing hardware support for the stability of wireless communication of industrial tablet computers.

[0104] As Figure 2As shown, in the RF signal processing unit, the frequency band characteristics of Bluetooth (RF_WBT) and 5G Wi-Fi (RF_WF_5G) signals are matched by differentiating filter networks. Among them, the Bluetooth signal processing link is configured by L1010 (10nH), L1008 (82nH) inductance and C1009 (18pF), C1006 (18pF) capacitor to form a π-type filter structure, as shown in the response characteristic curve of the Bluetooth filter branch in Figure 3 The network shows low insertion loss characteristics in the 2.4GHz frequency band, while the harmonic components form more than -20dB attenuation; the 5G Wi-Fi signal link is matched by L1007 (56nH) inductance and C1002 (18pF) capacitor to form a T-type matching network, which calibrates the input impedance to 50Ω system standard, and cooperates with the later-stage C1019 (10nF) decoupling capacitor to suppress the modulation interference of power supply noise on high-frequency signals, as shown in Figure 6 The suppression effect of high-frequency switching noise area. The physical isolation design of the two frequency band processing links PCB layout distance ≥3 times the signal wavelength avoids spatial coupling interference, and ensures independent transmission of multi-mode signals.

[0105] Further, the antenna interface unit integrates WBG_ANT composite antenna interface and AVDD33_WB power supply port, the former adopts a spring needle connector to realize low impedance connection between the antenna and the circuit, and the contact impedance is controlled within 0.5Ω; the latter suppresses the power supply ripple within 50mV through a multi-stage filter circuit composed of C1017 (100nF) and C1015 (100pF) capacitors, meeting the stringent requirements of high-frequency antenna modules on power supply stability. It should be understood that the ground design of the antenna interface adopts a star topology, and the ground pin of WBG_ANT is directly connected to the main ground plane, reducing the influence of ground loop noise on signal reception. This design forms a double barrier against interference with the filter network of the RF signal processing unit.

[0106] Further, the FM receiving unit constructs an interference detection link based on the voltage division principle, and the FM_ANT interface is connected to the R1006 (51kΩ) resistor and L1008 (47μH) inductance to form a high-pass filter voltage division network, which converts the high-frequency signal at the antenna end into a voltage signal suitable for the core control chip to collect. Among them, R1005 (33pF) capacitor and L1008 inductance form an LC resonant circuit to suppress the interference of out-of-band noise on amplitude detection, ensuring that the amplitude collection accuracy is better than ±2mV within the frequency band of 10kHz-100MHz. The output signal of the unit is directly connected to the ADC channel of U1002, providing real-time data support for interference level judgment, and the hardware architecture and the interference detection logic in Embodiment Five form a one-to-one physical implementation.

[0107] Further, the GPS signal processing unit takes the Elec_cn interface as the front end input, and realizes the passband width configuration through the adjustable LC filter network composed of L1005 (47nH) inductor and C1016 (22pF) capacitor, such as Figure 9 The hardware mapping of the middle bandpass filter parameter optimization, the 3dB bandwidth of the network is 20MHz in the initial state, when strong interference is detected, C1016 is switched to 47pF capacitance through GPIO control, and the bandwidth is narrowed to 10MHz accordingly. The low-noise design is adopted for the rear-stage U1004 amplifier, the power supply end is configured with C1018 (100nF) decoupling capacitor, the input and output ends are integrated with 50Ω matching resistor, the noise coefficient is ≤1.5dB in the low-noise amplification mode, the gain adjustment range covers 10dB-25dB, and the signal amplification demand in different interference scenes is met.

[0108] Further, the power management unit takes the VCN28_PMU port as the core, and realizes the independent power supply of each module through the distributed decoupling capacitor array (such as C1017, C1015, etc.). Among them, the AVDD18_WB power supply branch is configured with the parallel combination of 1μF tantalum capacitor and 100pF ceramic capacitor, and the low-frequency noise below 100kHz and the high-frequency noise above 10MHz are suppressed; the AVDD33_WB port adopts LC filter circuit (L1001 and C1020), and the power supply fluctuation is controlled within ±1%. It can be understood that the decoupling design of each power supply port and the filter network of the signal processing link form a cross-suppression structure of power-supply-signal, which effectively cuts off the coupling path of noise through the power supply system.

[0109] Further, the control chip U1002 serves as the circuit hub, integrates multiple groups of special interfaces to realize signal processing and logic control: the data interfaces such as CONN_BT_DATA and CONN_WF_CTRL0 adopt differential transmission mode, the signal rate supports up to 2.5Gbps, cooperates with the equal length processing of PCB trace, reduces the influence of clock skew on data synchronization; the power supply ports such as AVDD18_WB and AVDD33_WB adopt independent pin power supply, avoiding mutual interference of different voltage domains; the GPIO_GPS_LNA_EN pin controls the amplification mode switching of U1004 through level signal, the response time is ≤500ns, ensuring the real-time performance of interference detection and link adjustment, such as Figure 7 The hardware triggering mechanism of gain adaptive regulation. The state machine logic integrated in the chip can automatically generate filter parameter configuration instructions and amplifier control signals according to the amplitude detection results of the FM receiving unit, realize the full hardware execution of the anti-interference strategy.

[0110] The embodiment constructs a hardware architecture for independent processing of multi-band signals. Through the synergistic effect of a filter matching network, an antenna interface design, and power management, a physical layer barrier for front-end interference isolation is formed. The direct mapping of interference detection logic and hardware adjustment links is realized. The voltage division network of the FM receiving unit and the adjustable filter amplification module of the GPS signal processing unit provide accurate execution carriers for anti-interference algorithms. The interface configuration of the control chip and the distributed power management design ensure the stability of the collaborative work of multiple modules. The hardware architecture meets the stringent requirements of industrial-grade devices for temperature, vibration, and electromagnetic compatibility.

[0111] Through the circuit design of the embodiment, each functional module of the anti-interference method is converted into a specific hardware implementation. The organic combination of impedance matching, filter design, and control logic between units effectively improves the anti-interference ability of the wireless communication circuit in complex industrial environments, providing an engineering solution for reliable communication of ruggedized industrial tablets.

[0112] Embodiment Seven: To solve the problem of transmission loss of multi-band wireless signals in industrial environments due to impedance mismatching and out-of-band noise coupling, the embodiment further optimizes the filter matching architecture of the RF signal processing unit. Through differentiated multi-stage filter network design, targeted processing of Bluetooth and 5G Wi-Fi signals is realized, ensuring pure transmission and efficient power matching of different frequency band signals in complex electromagnetic environments.

[0113] In the RF_WBT signal processing path, the first filter network consists of an L1010 inductor, a C1009 capacitor, and a 50Ω matching resistor, forming a typical L-type filter structure. Among them, L1010 selects a 10nH high-frequency winding inductor, with a direct current resistance controlled within 0.2Ω, which can effectively suppress low-frequency noise interference outside the 2.4GHz frequency band; C1009 is an 18pF high-frequency ceramic capacitor, which forms a resonant circuit with the inductor, achieving an insertion loss of ≤0.5dB within the 2.4-2.485GHz passband, while forming an attenuation of ≥15dB for frequencies above 5GHz. The 50Ω matching resistor is connected in series in the signal path, ensuring the impedance consistency of the antenna end and the subsequent amplification circuit, reducing power loss caused by signal reflection. The standing wave ratio of this network is controlled below 1.2 within the full frequency band, meeting the requirements of Bluetooth signal transmission linearity.

[0114] Further, for the dual-band processing requirement of the RF_WF_5G signal, the second filter network and the third filter network form a cascaded filter structure. The second filter network adopts a π-type network constructed by L1008 inductance, C1006 capacitance and 50Ω resistance, wherein the 82nH inductance of L1008 and the 18pF capacitance of C1006 form impedance compensation for the 5.15-5.85GHz frequency band, and realize conjugate matching of input impedance and system impedance at the 5.2GHz center frequency point; the third filter network adopts a T-type matching structure composed of L1007 inductance, C1006 capacitance and 50Ω resistance, and the 56nH inductance of L1007 is optimized for the 5.8GHz frequency band, and cooperates with the capacitance adjustment of C1006 to accurately calibrate the equivalent impedance of the signal path to 50Ω standard. The cascaded design of the two-stage network forms double filtering for the 5G Wi-Fi signal, the first-stage π-type network suppresses low-frequency noise, and the second-stage T-type network filters out high-frequency harmonics, and together suppresses the out-of-band noise level to below -30dB.

[0115] It should be understood that the 50Ω resistors in each filter network adopt 0402 packaged thin film resistors, the parasitic inductance is controlled within 1nH, and the parasitic capacitance is less than 0.5pF, so as to avoid matching failure caused by element parameter deviation. At the same time, the inductance elements such as L1010, L1008 and L1007 adopt surface mount winding process, and the magnetic shielding structure design reduces the mutual inductance coupling between the filter networks. When laying out the PCB, the signal lines of Bluetooth and 5G Wi-Fi are separated by at least 2mm, and a complete ground plane is arranged between the two circuit boards, further reducing the influence of space electromagnetic coupling on signal integrity.

[0116] It can be understood that the parameter configuration of the three-stage filter network is optimized based on the transmission line theory, and the S parameters of each frequency band are analyzed by electromagnetic simulation software to ensure that the amplitude response flatness in the passband is ≤±0.3dB, and the group delay fluctuation is ≤50ps, meeting the requirements of signal phase linearity for high-speed data transmission. This customized filter matching design for different signal frequency bands not only guarantees the low-power transmission requirement of the Bluetooth signal, but also meets the high-bandwidth stability requirement of the 5G Wi-Fi signal, and is especially suitable for the coexistence environment of multi-mode wireless modules in industrial scenarios.

[0117] The benefits of the embodiment are that: by the differentiated design of the three-stage filter network, a complete RF signal processing link is constructed, and a dedicated impedance matching and noise suppression scheme is provided for the different frequency band characteristics of Bluetooth and 5G Wi-Fi signals. The element parameters and structural layout of each network are systematically optimized to effectively isolate the mutual interference of different frequency band signals at the physical layer, while ensuring low-loss transmission of each frequency band signal. This hardware-level filter matching design provides reliable support for the stable operation of wireless communication circuits in complex electromagnetic environments. The synergistic mechanism of multi-stage filtering and precise matching not only improves the sensitivity of signal reception but also reduces the spurious radiation of the transmitting end, meeting the stringent electromagnetic compatibility requirements of industrial-grade devices. By coordinating the design of the filter network and the antenna interface unit control chip, a full-link anti-interference system is formed from signal reception to processing, providing a reusable engineering implementation scheme for reinforcing the wireless communication performance of industrial tablets.

[0118] Through the above technical solutions, the embodiment constructs a hierarchical filter matching system in the RF signal processing unit. The element selection and structural design of each network closely revolves around the electromagnetic characteristics of the target frequency band, forming low-loss transmission of in-band signals and efficient suppression of out-of-band noise. Its hardware architecture cooperates with the antenna interface, power management, and other units in Embodiment Six to form a complete anti-interference wireless communication circuit, providing a solid hardware foundation for stable communication of industrial-grade devices in strong electromagnetic interference environments.

[0119] Embodiment Eight: To solve the problem of antenna interface signal being easily coupled by spatial electromagnetic noise and power ripple interference in industrial environments, the embodiment further optimizes the filter matching design of the antenna interface unit and the FM receiving unit. By coordinating the configuration of capacitive networks and resistive-inductive elements, noise suppression is achieved at the signal input end and the power supply end, forming a front-end protection barrier for the wireless communication module.

[0120] In the antenna interface unit, the C1005 and C1007 capacitors connected in parallel on both sides of the WBG ANT interface form a high-frequency noise bypass network. Among them, C1005 selects a 100pF ceramic capacitor, whose self-resonant frequency is higher than 5GHz, which can effectively filter out the ultra-high frequency spurious components in the antenna received signal; C1007 is a 1nF multilayer ceramic capacitor, which forms a low-impedance path for common-mode noise in the 100MHz-2GHz frequency band. The noise power density at the interface is suppressed to below -80dBm / Hz. The C1017 and C1015 capacitors configured at the AVDD33_WB power port form a multi-stage decoupling circuit: C1017 is a 100nF tantalum capacitor used to filter out low-frequency ripples below 10kHz; C1015 is a 100pF high-frequency capacitor that suppresses switch noise above 10MHz. Two-stage filtering controls the peak-to-peak value of the ripple voltage of the power output to within 30mV, ensuring the stability of the antenna module power supply.

[0121] Further, the FM receiving unit is configured with an impedance matching network by L1008 inductor and R1004 resistor, in which the inductive compensation of 47 μH inductance of L1008 and 51 kΩ resistance of R1004 is formed for FM band (87-108 MHz) to calibrate the input impedance to 75 Ω to match the antenna characteristics and reduce signal reflection loss. C1019 capacitor and R1005 resistor constitute an RC coupling filter circuit, in which 10 nF capacitance of C1019 realizes high-frequency signal direct-coupling, and 33 kΩ resistance of R1005 suppresses the influence of DC bias on the subsequent processing circuit, and both of them cooperatively filter out the out-of-band low-frequency noise to ensure the improvement of signal-to-noise ratio of the FM signal in the transmission process. It should be understood that L1008 and R1004 are arranged close to the FM ANT interface to shorten the signal path to reduce the influence of parasitic parameters, and C1019 and R1005 are close to the ADC input end of the core control chip to form a gradual noise filtering from the antenna to the processing unit.

[0122] It can be understood that the capacitive filtering design of the antenna interface unit and the inductive matching network of the FM receiving unit together constitute the physical layer barrier of the front-end signal processing: the former cuts off the spatial coupling and power conduction path of the noise through high-frequency bypass and power decoupling, and the latter improves the purity of the target signal through impedance calibration and out-of-band filtering. This layered design strategy improves the anti-interference ability of signal reception from the hardware level without increasing the complexity of the control logic, and is especially suitable for the wideband electromagnetic noise environment that exists continuously in the industrial scene.

[0123] The benefit of the embodiment is that the spatial coupling noise is effectively filtered out by configuring high-frequency bypass capacitors on both sides of the antenna interface, and the stability of the antenna module power supply is ensured by using the multi-stage decoupling circuit of the power port. The impedance matching network and RC coupling filter circuit of the FM receiving unit are optimized for the frequency band characteristics of the FM signal to reduce the reflection loss and noise in the signal transmission process. The parameter selection and layout design of each element are closely related to noise suppression and impedance matching to form a multi-stage protection system from the signal receiving end to the processing end. This hardware-level filtering and matching design can effectively suppress typical electromagnetic interference in industrial environments without relying on complex algorithms, providing a reliable front-end protection mechanism for the stable operation of wireless communication circuits. It forms a synergistic effect with other units in the system-level anti-interference scheme to improve the communication reliability of the rugged industrial tablet computer in complex electromagnetic environments.

[0124] A hardware anti-interference structure based on capacitive filtering and reactance matching is constructed in the antenna interface and the FM receiving unit through the embodiment, the function definition and layout design of each element comply with the electromagnetic compatibility principle, the noise suppression capability of the signal input end is effectively improved, a high-quality input signal is provided for the subsequent signal processing unit, the design idea is highly consistent with the reliability requirement of industrial-grade equipment, and a reusable front-end anti-interference hardware design paradigm is formed.

[0125] Embodiment nine: in order to solve the problem of the decline of the receiving sensitivity of the GPS signal caused by the multipath fading and the out-of-band noise interference in the industrial environment, the hardware architecture design of the GPS signal processing unit is further refined in the embodiment, the noise suppression and signal enhancement in the weak signal scene are realized through the cooperative configuration of the adjustable filtering network and the low-noise amplification circuit, and a high-quality input signal is provided for the positioning module.

[0126] In the GPS signal processing link, the radio frequency signal received by the Elec_cn interface is first subjected to band selection by the LC filtering network composed of the L1005 inductor and the C1016 capacitor. The L1005 is a high-frequency inductor with a value of 47nH, and its Q value is greater than 50, effectively suppressing the stray signals outside the passband; the C1016 is an adjustable capacitor array, and in the initial state, it is configured as 22pF, forming a filtering characteristic with a center frequency of 1.575GHz and a 3dB bandwidth of 20MHz with the L1005; when strong interference is detected, the capacitance is switched to 47pF through a control signal, and the bandwidth is narrowed to 10MHz accordingly, effectively filtering out the adjacent channel interference. The filtered signal enters the U1004 amplifier, the IN_GND input end of which adopts a differential ground design to reduce the influence of common-mode noise, and the RFOUT output end is integrated with a 50Ω matching resistor to ensure the impedance continuity of signal transmission; the VCC reference voltage end is powered through the LC filtering circuit composed of the L1001 inductor and the C1018 capacitor, and the 10nH inductance of the L1001 and the 100nF capacitance of the C1018 suppress the high-frequency ripple of the power supply end, control the voltage fluctuation within ±0.1V, and ensure the stability of the amplifier operation.

[0127] Further, the C1018 capacitor is arranged close to the power supply pin of the U1004, forming a local bypass path of high-frequency noise, reducing the modulation interference of the power supply noise on the amplification circuit; the L1001 inductor is connected in series in the main power supply path, cooperating with the decoupling action of the C1016 in the later stage to form a multi-stage power supply filtering structure. It should be understood that the amplification gain of the U1004 is dynamically adjusted by the GPIO signal of the core control chip, and in the default state, it works in the 10dB gain mode to reduce power consumption; when the filtering network detects that the signal amplitude is lower than the preset threshold, it automatically switches to the 25dB high-gain mode to compensate for the signal attenuation in the filtering process. The switching process is realized through an internal bias resistor network, the response time is controlled within nanoseconds, and the interruption of signal processing is avoided.

[0128] It can be understood that the cascade design of the LC filter network and the low-noise amplifier forms a double optimization of the GPS signal: the former suppresses out-of-band noise through bandwidth dynamic adjustment, and the latter compensates for signal loss through gain adaptive control, and the two work together to improve the signal-to-noise ratio to above the critical value required by the system processing. The seamless connection of the parameter adjustability at the hardware level and the control logic enables the GPS signal processing unit to adaptively adapt to the time-varying interference in the industrial environment without relying on external calibration to maintain stable signal reception performance.

[0129] The benefit of the embodiment is that the bandpass dynamic adjustment of the GPS signal is realized by the adjustable filter network composed of inductance and capacitance, and the signal-to-noise ratio of signal reception is effectively improved in combination with the gain adaptive mechanism of the low-noise amplifier; the parameter configuration and layout design of each element fully consider the high-frequency signal characteristics and power integrity requirements, the LC resonance characteristics of L1005 and C1016 ensure low-loss transmission of the target frequency band, the power filtering design of C1018 and L1001 cuts off the conduction path of noise, and the differential input and matching output structure of U1004 reduces the reflection and interference coupling in the signal transmission process. This collaborative design at the hardware level provides a guarantee for the reliable reception of the GPS signal in a complex electromagnetic environment, and in combination with the automatic adjustment logic of the core control chip, it forms the full-link anti-interference capability from signal filtering to amplification processing, effectively improving the practicability and stability of the wireless communication circuit in the industrial scene.

[0130] Example Ten: To solve the problems of frequency band interference, timing mismatch and power noise coupling when multiple modes of wireless signals coexist in the industrial environment, the embodiment constructs a wireless communication anti-interference system architecture for ruggedized industrial tablet computers, and through hierarchical integration of functional modules and collaborative design of control logic, realizes comprehensive improvement of multi-mode signal processing capability and system-level anti-interference performance.

[0131] Specifically, the multi-band signal processing module designs a differentiated filter matching link for the frequency band characteristics of different system signals. Among them, the RF_WBT signal filter branch forms an LC matching network through inductance L1010 and capacitance C1009, realizes 50Ω impedance calibration at the 2.4GHz Bluetooth frequency band, and suppresses the same frequency harmonic interference; the RF_WF_5G signal multi-stage filter network adopts a cascade structure of L1008 / L1007 inductance and C1006 capacitance, respectively filters the 5.15-5.35GHz and 5.725-5.85GHz sub-bands, and adjusts the combination of inductance and capacitance to improve the out-of-band suppression ratio to more than 40dB. It should be understood that high-frequency low-loss devices are selected for each frequency band filter element, and the PCB layout follows the one-way design of signal flow to avoid cross-coupling of different frequency band signal paths, and the continuous coverage of the surface layer ground copper foil builds a frequency band isolation barrier from a physical layer.

[0132] Further, the multi-mode cooperative control module takes control chip U1002 as the core, and the differential signal transmission mechanism is adopted for the data interfaces of CONN_BT_DATA / CLK and CONN_WF_CTRL0 / 1 / 2 configured by the multi-mode cooperative control module, which supports high-speed data interaction while reducing common mode noise influence. The anti-interference algorithm preset in the chip can dynamically adjust the interaction timing of Bluetooth and Wi-Fi signals according to real-time signal monitoring data: when detecting that there is same frequency interference in the 2.4GHz frequency band, the channel scanning period of the Wi-Fi signal is delayed to avoid the overlapping of the communication period with the Bluetooth communication; at the same time, based on the high-precision reference signal provided by the clock synchronization unit, the phase offset of the multi-mode signal is calibrated in real time to ensure the cooperative processing accuracy of different system signals in time domain and frequency domain. It can be understood that the PCB wiring of the data interface adopts equal length design, and the differential impedance is controlled within 100Ω±5%, which cooperates with signal integrity simulation optimization to reduce the influence of timing deviation on multi-mode cooperative processing.

[0133] Further, the power noise isolation module builds a three-level decoupling system around the VCN28_PMU power port, and the AVDD33_WB and AVDD18_WB power nodes are respectively configured with C1017 / C1015 / C1020 decoupling capacitor combinations. Among them, the 10μF electrolytic capacitor is used to filter out low-frequency ripples below 10kHz, the 100nF ceramic capacitor suppresses 100kHz-10MHz intermediate frequency noise, and the 100pF high-frequency capacitor handles switching noise above 10MHz, forming a full-band power noise suppression capability. The inductance L1001 is connected in series in the power main path, and forms an LC filter circuit with the rear-stage capacitor to control the ripple voltage of the power output within 50mV. It should be emphasized that the power supply circuit of each module adopts independent power pin design to avoid noise crosstalk of different functional units, and the power plane and signal layer are isolated by a complete ground layer to reduce the electromagnetic coupling of the power supply system to the high-frequency signal link.

[0134] Further, the anti-interference strategy adaptive module integrates the antenna interface monitoring and hardware parameter adjustment functions: the signal monitoring circuit of the WBG ANT and FM ANT interface converts the antenna end radio frequency signal into a direct current voltage signal through a voltage dividing resistor network and a coupling capacitor, inputs the ADC channel of the control chip to realize real-time intensity monitoring; the GPIO GPS LNA EN port adjusts the gain range of the U1004 amplifier and the capacitance value of the C1016 adjustable capacitor according to the monitoring result, realizes the dynamic adaptation of the filter bandwidth and the amplification gain. For example, when the GPS signal strength is lower than the preset threshold, the amplifier gain is automatically increased and the filter bandwidth is narrowed, which enhances the target signal while suppressing the out-of-band interference. The adjustment process is directly responded by the hardware logic, ensuring the microsecond-level interference processing time.

[0135] Further, the storage unit adopts the EEPROM with SPI interface, pre-stores the frequency band configuration parameters, signal threshold and dynamic adjustment strategy of the anti-interference algorithm, supports the real-time reading and runtime parameter update of the control chip U1002. The storage content includes the default parameters of the filter network in different industrial scenes, the priority scheduling table of multi-mode signal interaction, the combination configuration scheme of the power decoupling capacitor, etc., to ensure the consistency of the strategy execution of the system in complex environments. The clock synchronization unit selects a temperature compensated crystal oscillator (TCXO) to provide a differential clock signal with a frequency stability of ±0.5ppm, which is directly connected to the clock input end of the multi-band signal processing module and the multi-mode collaborative control module, and through the clock tree equalization design, the clock skew of each module is controlled within 100ps, providing an accurate reference for nanosecond-level timing calibration.

[0136] It can be understood that the system function modules realize the integration of data flow and control flow through the control chip U1002: the multi-band signal processing module completes the physical layer optimization of the front-end signal, the multi-mode collaborative control module realizes the timing coordination of the protocol layer, the power supply noise isolation module builds the noise barrier of the power supply system, the anti-interference strategy adaptive module provides real-time environment perception and hardware adjustment capability, and the storage unit and the clock synchronization unit provide data support and timing reference for strategy execution respectively. This hierarchical design architecture not only retains the immediacy of hardware-level anti-interference, but also realizes adaptive adjustment at the system level through algorithm scheduling, effectively coping with the wideband, time-varying electromagnetic interference environment in industrial scenes.

[0137] The benefits of the embodiment are that the independent filtering and impedance matching of different mode signals are realized through the differentiated hardware design of the multi-band signal processing module; the dynamic timing adjustment and phase calibration mechanism of the multi-mode collaborative control module effectively avoids the interactive interference of multi-mode signals; the three-stage decoupling design of the power noise isolation module cuts off the power conduction path of the noise; the real-time monitoring and hardware parameter adjustment of the anti-interference strategy adaptive module improve the response capability of the system to complex interference; the configuration of the storage unit and the clock synchronization unit provides data basis and timing guarantee for the stable execution of the anti-interference strategy, and the hierarchical architecture design of the system level not only enhances the anti-interference performance of the wireless communication circuit, but also improves the communication stability of the rugged industrial tablet computer in the extreme electromagnetic environment.

[0138] Although the present application has been described above with reference to the preferred embodiments, it is to be understood that the application is not limited to the above-described embodiments, and various modifications and changes can be made by those skilled in the art without departing from the spirit of the present application, and such modifications and changes should fall within the scope of the appended claims and their equivalents.

Claims

1. A method for enhancing the wireless communication anti-interference capabilities of a ruggedized industrial tablet PC, characterized by the following steps: include: A multi-stage filtering network is used to perform frequency band-specific filtering and impedance matching on RF_WBT Bluetooth signals and RF_WF_5G wireless signals. The multi-stage filtering network includes an RF_WBT signal filtering branch composed of an L1010 inductor and a C1009 capacitor, a first RF_WF_5G signal filtering branch composed of an L1008 inductor and a C1006 capacitor, and a second RF_WF_5G signal filtering branch composed of an L1007 inductor and a C1006 capacitor, which is used to eliminate frequency band crosstalk and improve signal purity. The control chip U1002 synchronously processes Wi-Fi, Bluetooth, GPS and FM signals. An anti-interference algorithm based on signal strength threshold is used to adjust the data interface interaction timing of Bluetooth and Wi-Fi signals to dynamically calibrate the gain and phase of the signal link in order to avoid parallel interference of multi-mode signals. The circuit is powered through the VCN28_PMU power port, and decoupling capacitors are configured at the AVDD33_WB and AVDD18_WB power nodes for high-frequency noise filtering, voltage stabilization, and reducing the impact of power fluctuations on RF processing. The signal strength of the WBG_ANT and FM_ANT antenna interfaces is monitored in real time. When the frequency band interference exceeds the threshold, the gain mode of the U1004 amplifier in the GPS signal link is dynamically switched through the GPIO_GPS_LNA_EN port, and the GPS signal filtering parameters of the Elec_cn interface are adjusted for stable signal reception in complex environments. The steps of the anti-interference algorithm include: The bit error rate data of Bluetooth signals is collected in real time through the CONN_BT_DATA and CONN_BT_CLK interfaces, and the throughput parameters of Wi-Fi signals are obtained through the CONN_WF_CTRL0 / 1 / 2 interfaces. When the Bluetooth signal bit error rate is detected to exceed the first preset percentage and the Wi-Fi throughput drops by the second preset percentage, the time division multiplexing mechanism is triggered. By adjusting the internal timer of the control chip U1002, the channel occupancy time of the Bluetooth and Wi-Fi signals is staggered by 50μs. Phase synchronization calibration of orthogonal baseband data for Bluetooth and Wi-Fi signals is performed via BT_QP / QN and WF_QP / QN interfaces to eliminate phase noise interference from signals in the same frequency band and avoid channel contention when multiple modes of signals are running concurrently.

2. The method for anti-interference wireless communication of a ruggedized industrial tablet PC as described in claim 1, characterized in that, The first filtering branch performs bandpass filtering on the RF_WBT signal through an LC series network consisting of inductor L1010 and capacitor C1009 to filter out spurious signals outside the 2.4GHz band. The second and third filtering branches are cascaded to form a π-type filtering network, in which inductor L1008 and capacitor C1006 constitute a high-frequency pre-filtering unit, and inductor L1007 and capacitor C1006 constitute a secondary filtering unit. Together, they perform noise suppression and impedance matching on the RF_WF_5G signal in the 5GHz band to ensure that the signal transmission loss is lower than a preset threshold.

3. The method for anti-interference wireless communication of a ruggedized industrial tablet PC as described in claim 1, characterized in that, The decoupling capacitor configuration method includes: connecting a 100nF C1017 capacitor and a 100pF C1011 capacitor in parallel at the AVDD33_WB power port to filter out low-frequency noise below 100kHz and high-frequency noise above 10MHz, respectively; and connecting a 10nH L1001 inductor and a 22μF C1020 capacitor in series at the VCN28_PMU power input to form an LC filter circuit to suppress surge noise at the power input terminal, ensuring that the power supply voltage fluctuation range of the control chip U1002 does not exceed ±1%.

4. The method for anti-interference wireless communication of a ruggedized industrial tablet PC as described in claim 1, characterized in that, The frequency band interference detection steps include: real-time acquisition of FM signal amplitude through a voltage divider network consisting of resistor R1006 and inductor L1008 of the FM_ANT interface; when the amplitude is below 50mV, it is determined to be a strong interference environment; by adjusting the filtering parameters of capacitor C1016 and inductor L1005 in the GPS signal processing link, the passband bandwidth of the GPS signal is reduced from 20MHz to 10MHz, and the low-noise amplification mode of amplifier U1004 is activated to increase the signal gain by 15dB.

5. A wireless communication circuit for implementing the anti-interference method for wireless communication of a ruggedized industrial tablet PC as described in any one of claims 1-4, characterized in that, include: An RF signal processing unit is used to filter and match RF_WBT and RF_WF_5G signals. The RF signal processing unit includes inductors L1010, L1008, L1007 and capacitors C1009 and C1006. An antenna interface unit for receiving and transmitting Wi-Fi and Bluetooth signals, the antenna interface unit including a WBG_ANT interface and an AVDD33_WB power port; An FM receiver unit is used to receive and process FM signals. The FM receiver unit includes an FM_ANT interface, resistors R1006 and R1005, and inductor L1008. A GPS signal processing unit for receiving and processing GPS signals, the GPS signal processing unit includes an Elec_cn interface, an inductor L1005, a capacitor C1016 and an amplifier U1004; A power management unit is used to provide a stable power supply for the entire module. The power management unit includes a VCN28_PMU power port and multiple capacitors. A control chip U1002 is used to process Wi-Fi, Bluetooth, GPS and FM signals and interact with external devices through multiple pins. The control chip U1002 has multiple power ports and data interfaces.

6. The wireless communication circuit as described in claim 5, characterized in that, The RF signal processing unit further includes: The first filtering network, including inductor L1010, capacitor C1009 and resistor 50Ω, is used to filter and match the RF_WBT signal; The second filtering network, including inductor L1008, capacitor C1006 and resistor 50Ω, is used to filter and match the RF_WF_5G signal; The third filtering network, which includes inductor L1007, capacitor C1006 and resistor 50Ω, is also used to filter and match the RF_WF_5G signal.

7. The wireless communication circuit as described in claim 5, characterized in that, The antenna interface unit further includes: Capacitors C1005 and C1007 are connected to both sides of the WBG_ANT interface for filtering. Capacitors C1017 and C1015 are connected to the AVDD33_WB power supply port for power filtering. The FM receiving unit also includes: Inductor L1008 and resistor R1004 are used for impedance matching and filtering of FM signals; Capacitor C1019 and resistor R1005 are used for coupling and filtering the FM signal.

8. The wireless communication circuit as described in claim 5, characterized in that, The GPS signal processing unit further includes: Inductor L1005 and capacitor C1016 are used to filter GPS signals; Amplifier U1004 has an input terminal IN_GND, an output terminal RFOUT, and a reference voltage terminal VCC, and is used to amplify and process the filtered GPS signal. Capacitor C1018 and inductor L1001 are used for filtering and matching GPS signals.

9. A ruggedized industrial tablet PC wireless communication anti-interference system, integrating the wireless communication circuit as described in any one of claims 5-8, characterized in that, include: The multi-band signal processing module is used for multi-band signal filtering and matching, including the RF_WBT signal filtering branch, the RF_WF_5G signal multi-level filtering network and the corresponding inductors L1010 / L1008 / L1007 and capacitors C1009 / C1006, so as to realize independent filtering and impedance matching of signals of different frequency bands. The multi-mode cooperative control module includes the control chip U1002 and its configured CONN_BT_DATA / CLK and CONN_WF_CTRL0 / 1 / 2 data interfaces, which are used to perform multi-mode signal cooperative processing and dynamically adjust the interaction timing and phase calibration parameters of multi-mode signals through a preset anti-interference algorithm. The power supply noise isolation module includes the VCN28_PMU power port, AVDD33_WB / 18_WB power nodes and decoupling capacitors C1017 / C1015 / C1020, which are used to achieve power supply noise filtering and stable power supply. The anti-interference strategy adaptive module includes a signal monitoring circuit for the WBG_ANT / FM_ANT antenna interface, a GPIO_GPS_LNA_EN port, and a U1004 amplifier control unit, which is used to monitor the signal strength in real time and dynamically adjust the filtering parameters and amplification gain. The storage unit is used to store preset anti-interference algorithm parameters, signal threshold configurations, and dynamic adjustment strategies to support real-time access by the control chip U1002. A clock synchronization unit is used to provide a high-precision clock signal to ensure nanosecond-level timing calibration accuracy of Bluetooth and Wi-Fi signals. The clock synchronization unit is electrically connected to a multi-band signal processing module and a multi-mode collaborative control module to realize the steps of the method for strengthening the anti-interference of wireless communication in industrial tablet PCs.

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