A method of wireless signal processing

Abstract

The present application relates to the technical field of wireless signal processing, and particularly relates to a wireless signal processing method, which comprises the following steps: a sending end of a first wireless network acquires an original baseband signal comprising an in-phase component and a quadrature component; an interchange process is performed on the in-phase component and the quadrature component to generate an interchanged signal; the interchanged signal is sent; an inverse interchange process is performed on the recovered signal obtained after a receiving end of the first wireless network receives the wireless signal to obtain communication data. The interchange process can be realized by using a cache exchange, symbol inversion or frequency domain exchange mode. The signal structure is changed through the interchange process, so that the first wireless network can normally communicate, while the second wireless network device cannot demodulate the signal due to not performing the corresponding inverse interchange process, thereby realizing network isolation. The present application also supports mode switching and configuration information synchronization, enhances device compatibility, effectively solves the problem of co-channel interference, and improves the communication reliability of industrial internet of things.

Description

Technical Field

[0001] This invention relates to the field of wireless signal processing technology, and more particularly to a method for wireless signal processing. Background Technology

[0002] In industrial IoT applications, there is a risk of mutual interference between the first wireless network (e.g., industrial wireless network WIA) and the second wireless network (e.g., commercial WiFi wireless LAN). The preamble sequence, as the synchronization signal part of the wireless frame, has a specific pattern used for device identification and frame synchronization. By modifying the preamble sequence to design unique sequences for the first and second wireless networks, the device can distinguish the signal source based on the difference in sequence characteristics, thereby processing only frames with matching sequences and ignoring other network signals, achieving effective isolation between networks, reducing interference and improving communication reliability.

[0003] Existing technologies for isolating the first and second wireless networks in modified preamble sequences have the following technical drawbacks. Specifically, in industrial IoT applications, when the first and second wireless networks operate on the same frequency band, their signals overlap in the airspace due to similar protocol formats, resulting in co-channel interference and decreased communication reliability. For example, in a smart manufacturing environment, the first wireless network (e.g., Industrial Wireless Networking (WIA)) is used for real-time transmission of industrial robot control commands, while the second wireless network is simultaneously used for data transmission from employee mobile devices. When the two networks coexist, the second wireless network signal interferes with the first wireless network control signal, causing command loss or delay, thereby affecting production line stability and efficiency. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a wireless signal processing method that solves the technical problem of signal interference and decreased communication reliability caused by the coexistence of a first wireless network and a second wireless network in the same frequency band. Here, the first wireless network and the second wireless network refer to two different wireless communication protocols or network types. For example, in an industrial IoT scenario, the first wireless network could be an industrial wireless network, and the second wireless network could be a commercial WiFi network. However, this invention is not limited to these and is applicable to any wireless communication scenario requiring network isolation.

[0005] To solve the above-mentioned technical problems, the specific technical solution of the present invention is as follows:

[0006] The present invention provides a method for wireless signal processing, comprising:

[0007] Step 1: The transmitting end of the first wireless network acquires the original baseband signal, which is a time-domain signal and includes in-phase and quadrature components.

[0008] Step 2: Based on the original baseband signal, perform a swapping process on the in-phase component and the quadrature component to generate a swapped signal; wherein, the swapping process includes time-domain swapping or frequency-domain swapping.

[0009] Step 3: Send the exchanged signals into the airspace;

[0010] Step 4: The receiver of the first wireless network receives wireless signals from the airspace as received signals;

[0011] Step 5: Perform inverse swapping processing on the received signal. The inverse swapping processing is the reverse of the swapping processing to obtain the recovered signal.

[0012] Step 6: Demodulate the recovered signal to obtain communication data. Specifically, when the transmitting end of the first wireless network performs the swapping process and the receiving end of the first wireless network performs the corresponding reverse swapping process, communication is completed within the first wireless network. When the transmitting end of the first wireless network performs the swapping process, but the receiving end of the second wireless network does not perform the corresponding reverse swapping process, the second wireless network cannot demodulate the signal from the first wireless network. Alternatively, when the transmitting end of the second wireless network does not perform the swapping process, but the receiving end of the first wireless network performs the reverse swapping process, the first wireless network cannot demodulate the signal from the second wireless network.

[0013] Furthermore, in the wireless signal processing method of the present invention, step 2 involves performing a swapping process on the in-phase component and the quadrature component to generate a swapped signal, including:

[0014] Based on the original baseband signal, the first numerical sequence of the in-phase component and the second numerical sequence of the quadrature component are separated;

[0015] Write the first numerical sequence into the first buffer area, and write the second numerical sequence into the second buffer area;

[0016] Read the first numerical sequence from the first buffer area and use the read first numerical sequence as a new orthogonal component;

[0017] Read the second numerical sequence from the second buffer area and use the read second numerical sequence as a new in-phase component;

[0018] The new in-phase component is combined with the new quadrature component to generate an interchanged signal.

[0019] Furthermore, in the wireless signal processing method of the present invention, step 2 involves performing a swapping process on the in-phase component and the quadrature component to generate a swapped signal, including:

[0020] Based on the original baseband signal, the first numerical sequence of the in-phase component and the second numerical sequence of the quadrature component are separated;

[0021] The first numerical sequence is sent to the first data processing process, and the second numerical sequence is sent to the second data processing process;

[0022] In the first data processing process, the sign of the first numerical sequence is reversed to obtain the first processed sequence;

[0023] The second numerical sequence is obtained from the second data processing procedure, and the second numerical sequence is used as a new in-phase component.

[0024] The first processed sequence is used as a new orthogonal component;

[0025] The new in-phase component is combined with the new quadrature component to generate an interchanged signal.

[0026] Furthermore, in the wireless signal processing method of the present invention, step 2 involves performing a swapping process on the in-phase component and the quadrature component to generate a swapped signal, including:

[0027] Perform a Fast Fourier Transform (FFT) on the original baseband signal to convert the original time-domain baseband signal into a frequency-domain signal, generating a frequency-domain signal, which includes a frequency-domain in-phase component sequence and a frequency-domain quadrature component sequence.

[0028] The values ​​of the in-phase component sequence in the frequency domain are exchanged with the values ​​of the quadrature component sequence in the frequency domain to generate the exchanged frequency domain signal.

[0029] Perform an inverse fast Fourier transform (IFFT) on the swapped frequency domain signal to convert the frequency domain signal back to the time domain signal, generating the swapped signal.

[0030] Furthermore, in the wireless signal processing method of the present invention, step 5 involves performing an inverse interchange process on the received signal to obtain a recovered signal, including:

[0031] Perform a Fast Fourier Transform (FFT) on the received signal to convert the time-domain received signal into a received frequency-domain signal, generating a received frequency-domain signal, which includes a received frequency-domain in-phase component sequence and a received frequency-domain quadrature component sequence.

[0032] The values ​​of the received frequency domain in-phase component sequence and the values ​​of the received frequency domain quadrature component sequence are swapped to generate the frequency domain signal after inverse swapping.

[0033] Perform an inverse fast Fourier transform (IFFT) on the frequency domain signal after the inverse exchange to convert the frequency domain signal back to the time domain signal.

[0034] Furthermore, in the wireless signal processing method of the present invention, step 3 further includes:

[0035] The interchanged signal is transmitted and processed; the interchanged signal is a time-domain signal.

[0036] Perform pulse shaping filtering on the interchanged signals to obtain the shaped signal;

[0037] The shaped signal is digitally up-converted to shift the baseband spectrum to the intermediate frequency spectrum to generate a digital intermediate frequency signal;

[0038] The digital intermediate frequency signal is converted from digital to analog to generate an analog transmission signal for transmission.

[0039] Furthermore, in the wireless signal processing method of the present invention, step 5 further includes:

[0040] The received signal is processed: the received signal is an analog signal;

[0041] The received signal is converted from analog to digital to generate a digital received signal, which is a time-domain signal;

[0042] The digital received signal is digitally down-converted to shift the intermediate frequency spectrum back to the baseband spectrum, generating a down-converted signal, which is a time-domain signal.

[0043] Perform matched filtering on the down-converted signal to obtain the inverted interchange signal, which is a time-domain signal;

[0044] The reverse interchange process on the received signal is to perform the reverse interchange process on the signal to be reverse interchanged to obtain the recovered signal.

[0045] Furthermore, the wireless signal processing method of the present invention further includes:

[0046] Receive mode switching commands including mode identifiers;

[0047] Parse the pattern identifier to obtain the current pattern indication;

[0048] If the current mode indicates the first mode, then the control signal processing path performs the swapping process and the reverse swapping process;

[0049] If the current mode indicates the second mode, the control signal processing path skips the swapping process and the reverse swapping process.

[0050] Furthermore, in the wireless signal processing method of the present invention, if the current mode indicates a first mode, the control signal processing path performs the swapping process and the reverse swapping process, including:

[0051] In the transmission path, the baseband signal is directed to the swapping process, and the result of the swapping process is directed to the subsequent transmission processing steps;

[0052] In the receiving path, the signal after receiving and processing is directed to the inverse interchange process, and the recovered signal obtained from the inverse interchange process is directed to the demodulation process.

[0053] Furthermore, the wireless signal processing method of the present invention further includes:

[0054] At the transmitting end, the configuration information indicating the current mode is encoded into a bit sequence, and the bit sequence is carried in the physical layer frame structure and transmitted.

[0055] At the receiving end, the bit sequence is decoded from the received physical layer frame structure;

[0056] The current mode indication used by the sending end is determined based on the decoded bit sequence;

[0057] Based on the determined current mode indication, the corresponding reverse swapping process is set at the receiving end.

[0058] The beneficial effects of this invention are:

[0059] This invention transforms the in-phase and quadrature components of the original baseband signal through a swapping process to generate a swapped signal. At the receiving end, a corresponding inverse swapping process is performed to recover the signal, enabling normal communication between the first wireless network devices. However, the second wireless network device, lacking the inverse swapping process, cannot demodulate the swapped signal, thus effectively isolating co-channel interference. This method directly manipulates signal components without modifying the preamble sequence, simplifying the implementation process and reducing processing overhead. It also supports mode switching and configuration information synchronization, enhancing device compatibility and network adaptability, and improving communication reliability in industrial IoT scenarios. Attached Figure Description

[0060] To more clearly illustrate the technical solution of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on the drawings without creative effort.

[0061] Figure 1 This is a flowchart illustrating the wireless signal processing method of the present invention. Detailed Implementation

[0062] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention. The technical solutions provided by various embodiments of this invention will be described in detail below with reference to the accompanying drawings.

[0063] To better understand the purpose of this invention, the invention will now be described in further detail.

[0064] Please see Figure 1 This invention provides a wireless signal processing method applied to a communication system comprising a first wireless network and a second wireless network. The first and second wireless networks are two wireless networks employing different communication protocols or signal processing methods. For example, in an industrial IoT scenario, the first wireless network may be an industrial control network requiring high reliability, while the second wireless network may be a commercial wireless local area network (WLAN). However, this invention is not limited to these. The core of this method lies in achieving reliable communication within the first wireless network and signal isolation between it and the second wireless network through specific processing of baseband signal components. The method includes the following steps:

[0065] Step 1: The transmitting end of the first wireless network acquires the original baseband signal, which is a time-domain signal and includes in-phase and quadrature components.

[0066] Step 2: Based on the original baseband signal, perform a swapping process on the in-phase component and the quadrature component to generate a swapped signal; wherein, the swapping process includes time-domain swapping or frequency-domain swapping.

[0067] Step 3: Send the exchanged signals into the airspace;

[0068] Step 4: The receiver of the first wireless network receives wireless signals from the airspace as received signals;

[0069] Step 5: Perform inverse swapping processing on the received signal. The inverse swapping processing is the reverse of the swapping processing to obtain the recovered signal.

[0070] Step 6: Demodulate the recovered signal to obtain communication data; wherein, when the transmitting end of the first wireless network performs the swapping process and the receiving end of the first wireless network performs the corresponding reverse swapping process, communication is completed within the first wireless network; when the transmitting end of the first wireless network performs the swapping process but the receiving end of the second wireless network does not perform the corresponding reverse swapping process, the second wireless network cannot demodulate the signal from the first wireless network; or, when the transmitting end of the second wireless network does not perform the swapping process but the receiving end of the first wireless network performs the reverse swapping process, the first wireless network cannot demodulate the signal from the second wireless network.

[0071] At the transmitting end of the first wireless network, the acquisition of the raw baseband signal typically originates from communication data generated by the digital signal processing module. This baseband signal includes in-phase and quadrature components, which exist in the form of numerical sequences, representing the real and imaginary parts of the signal, respectively. For example, in a smart manufacturing scenario, control commands are converted into baseband signals by an encoder, laying the foundation for subsequent processing.

[0072] Based on the original baseband signal, the interchange processing achieves signal transformation by manipulating the in-phase and quadrature components. One specific implementation involves separating the first numerical sequence of the in-phase component and the second numerical sequence of the quadrature component. The first numerical sequence is written to a first buffer region, and the second numerical sequence is written to a second buffer region. Then, the first numerical sequence is read from the first buffer region as the new quadrature component, and the second numerical sequence is read from the second buffer region as the new in-phase component. Finally, these are combined to generate the interchanged signal. This method utilizes buffer swapping to perform component interchange simply and efficiently, making it suitable for industrial environments with high real-time requirements. Another approach is to perform a Fast Fourier Transform (FFT) in the frequency domain to obtain the frequency domain signal, swap the values ​​of the in-phase and quadrature component sequences in the frequency domain, and then generate the interchanged signal through an inverse FFT. This method leverages the characteristics of the frequency domain to enhance processing flexibility. The core of the interchange processing lies in changing the signal structure, making subsequent transmissions unique.

[0073] The exchanged signals then enter the transmission phase. First, pulse shaping filtering is performed to optimize spectral efficiency and reduce inter-symbol interference. Next, digital up-conversion is executed to shift the baseband spectrum to the intermediate frequency spectrum, generating a digital intermediate frequency signal. Finally, an analog transmission signal is generated through digital-to-analog conversion and radiated into the airspace via an antenna. This series of processes ensures the integrity and anti-interference capability of the signal during transmission. For example, in the control link of industrial robots, shaping filtering can adapt to channel characteristics.

[0074] The receiver of the first wireless network captures wireless signals from the airspace as received signals. These signals may include mixed interference from the first or second wireless network, thus demonstrating the application of the communication system. The receiving process includes analog-to-digital conversion to convert the analog signal into a digital received signal, followed by digital down-conversion to shift the intermediate frequency spectrum back to the baseband spectrum, generating a down-converted signal. This down-converted signal is then subjected to matched filtering to obtain the signal to be inverted, preparing for inverse processing.

[0075] The inverse swapping process is performed on the received signal. As the reverse of the swapping process, it involves, for example, performing a Fast Fourier Transform (FFT) on the received signal in the frequency domain to generate a received frequency domain signal, swapping the values ​​of the in-phase and quadrature component sequences in the received frequency domain, and then generating the recovered signal through an inverse FFT. This inverse operation restores the original signal characteristics, ensuring that only the first matched wireless network receiver can correctly demodulate it, thus corresponding to the aforementioned definition. The recovered signal is finally sent to the demodulation module, where standard demodulation algorithms are used to extract communication data, completing the communication link.

[0076] When the transmitting end of the first wireless network performs a swapping process and the receiving end performs the corresponding reverse swapping process, the signal flows seamlessly within the first wireless network, achieving reliable communication. Conversely, if the signal after the swapping process at the transmitting end of the first wireless network is received by the receiving end of the second wireless network, but the receiving end of the second wireless network has not performed the reverse swapping process, the signal structure mismatch will lead to demodulation failure. Similarly, if the standard signal from the transmitting end of the second wireless network is received by the receiving end of the first wireless network and the reverse swapping process is performed, it will also fail to demodulate due to signal distortion, thus clearly illustrating the isolation principle.

[0077] At the transmitting end of the first wireless network, after the in-phase and quadrature components of the original baseband signal are separated, the first numerical sequence is written to the first buffer area, and the second numerical sequence is written to the second buffer area. The buffer areas employ a double-buffering mechanism, such as a first-in-first-out queue, to ensure continuous data flow. The write operation is controlled by the memory management unit of the digital signal processor, and the sequence is stored in the sampling order. When reading the first numerical sequence from the first buffer area, the read pointer and write pointer are synchronized to avoid data conflicts, and the read data is used as the new quadrature component. Similarly, the second numerical sequence is read from the second buffer area as the new in-phase component. Buffer swapping realizes the physical interchange of components, and the combination process merges the new in-phase component and the new quadrature component into a complex signal, forming the swapped signal. This process is implemented based on a hardware description language, deployed in an FPGA, and is suitable for high real-time industrial scenarios.

[0078] In another interchange processing method, the separated first numerical sequence is sent to the first data processing process, and the second numerical sequence is sent to the second data processing process. The first data processing process performs numerical sign inversion, for example, by inverting each sample value through binary two's complement operations to obtain the first processed sequence. The second data processing process directly outputs the second numerical sequence without modification. The first processed sequence serves as the new quadrature component, and the second numerical sequence serves as the new in-phase component. The combination stage integrates the two to generate the interchanged signal. Sign inversion introduces phase shift, enhancing the diversity of signal transformation and effectively distinguishing network sources in an industrial IoT environment.

[0079] Frequency domain swapping converts the original baseband signal into a frequency domain representation by performing a Fast Fourier Transform (FFT). The frequency domain signal consists of a sequence of in-phase components and a sequence of quadrature components, with the real and imaginary parts of the corresponding frequency points. The swapping operation iterates through each frequency point, interchanging the values ​​of the in-phase and quadrature components, for example, through array index swapping. The swapped frequency domain signal is then restored to the swapped time domain signal by an Inverse Fast Fourier Transform (IFT). Frequency domain processing leverages spectral symmetry to improve signal integrity in factory environments with severe multipath interference.

[0080] The inverse swapping process at the receiving end corresponds to the frequency domain approach, performing a Fast Fourier Transform (FFT) on the received signal to generate the received frequency domain signal. The values ​​of the received frequency domain in-phase component sequence and the received frequency domain quadrature component sequence are swapped, and the frequency domain signal after the inverse swap is converted into a recovered signal through an inverse FFT. This inverse operation restores the swapping effect at the transmitting end, ensuring that only the first matched network device can correctly demodulate. In the industrial robot control link, this process is synchronized with the transmitting end to maintain communication reliability.

[0081] At the transmitting end of the first wireless network, pulse shaping filtering is performed on the swapped signal to generate a shaped signal. Pulse shaping filtering uses a root-raised cosine filter to convolve the swapped signal, limiting the signal bandwidth and suppressing inter-symbol interference. For example, in industrial robot control scenarios, pulse shaping filtering optimizes the signal waveform to adapt to multipath propagation environments. The shaped signal then enters the digital up-conversion stage, where a digital mixer shifts the baseband spectrum to the intermediate frequency (IF) spectrum. The digital mixer multiplies the shaped signal with a sinusoidal signal generated by a local numerically controlled oscillator, achieving spectrum shifting and outputting a digital IF signal. The digital IF signal is converted into an analog transmission signal via a digital-to-analog converter (DAC). The DAC reconstructs the discrete digital sequence into a continuous-time analog waveform at a fixed sampling rate. The analog transmission signal is then sent to the RF front-end for power amplification and antenna radiation. The transmission processing chain ensures signal integrity and anti-interference capability during transmission. Pulse shaping filtering first optimizes the signal shape, digital up-conversion completes the frequency domain conversion, and the DAC achieves the transition from digital to analog.

[0082] At the receiving end, the received signal undergoes analog-to-digital conversion to generate a digital received signal. The analog-to-digital converter samples and quantizes the analog wireless signal captured by the antenna, converting it into a discrete digital sequence. The digital received signal enters the digital down-conversion stage, where a digital mixer shifts the intermediate frequency spectrum back to the baseband spectrum. The digital mixer multiplies the digital received signal with a cosine signal generated by a local numerically controlled oscillator, filtering out high-frequency components and outputting the down-converted signal. The down-converted signal undergoes matched filtering. The matched filter uses coefficients matched to the pulse shaping filter at the transmitting end, performing convolution operations to maximize the signal-to-noise ratio, resulting in the inverse-transformation signal. The inverse-transformation process directly applies to the inverse-transformation signal, restoring the original signal characteristics through the inverse operation. Analog-to-digital conversion digitizes the signal, digital down-conversion restores the frequency domain, matched filtering optimizes signal detection, and the sequence of steps ensures accurate recovery of the received signal.

[0083] The mode switching function is implemented by receiving a mode switching command that includes a mode identifier. The mode switching command comes from the network management entity or the user configuration interface, and the mode identifier is encoded as a fixed-length bit sequence. When parsing the mode identifier, the embedded processor reads the bit sequence and decodes the current mode indication. When the current mode indication is the first mode, the signal processing path enables interchange and reverse interchange processing. When the current mode indication is the second mode, the signal processing path bypasses interchange and reverse interchange processing. The mode switching command dynamically adjusts the device behavior through control logic to adapt to different network environments. The parsing process ensures accurate mode recognition and consistent execution of control commands.

[0084] In the first mode, the control signal processing path performs interchange and inverse interchange processing. In the transmit path, the baseband signal is guided to the interchange processing module via a multiplexer, and the interchange processing result is sent to subsequent transmit processing steps. In the receive path, the matched-filtered signal is guided to the inverse interchange processing module via a multiplexer, and the recovered signal output from the inverse interchange processing is guided to the demodulation module. The multiplexer is controlled by the mode indication signal to achieve path switching. The transmit path selection ensures that the signal undergoes interchange transformation, and the receive path selection ensures inverse transformation matching. Path control and mode indication are synchronized to maintain communication consistency.

[0085] Configuration information encoding is completed at the transmitting end, with the configuration information indicating the current mode encoded as a bit sequence. This bit sequence is carried in reserved fields within the physical layer frame structure, such as specific bits in the frame control field. The transmitting end inserts the bit sequence into the physical layer frame header and transmits it along with the wireless signal. The receiving end decodes the bit sequence from the received physical layer frame structure; the decoding process involves frame parsing circuitry to extract reserved field values. Based on the decoded bit sequence, the receiving end determines the current mode indication used by the transmitting end, such as identifying the mode type. The receiving end then performs the corresponding inverse switching process, loading mode parameters through the configuration register. These encoding and decoding steps ensure mode synchronization between the transmitting and receiving ends, and the transmission of configuration information guarantees mode matching, enhancing system compatibility.

[0086] In a smart manufacturing scenario, the transmitter of the first wireless network acquires the raw baseband signal, such as industrial robot control commands, which are converted into digital signals including in-phase and quadrature components by an encoder. The in-phase component of the raw baseband signal is represented by a first numerical sequence, and the quadrature component by a second numerical sequence. The transmitter performs a swapping process on the in-phase and quadrature components to generate a swapped signal. One implementation of the swapping process involves separating the first numerical sequence of the in-phase component and the second numerical sequence of the quadrature component, writing the first numerical sequence into a first buffer area, and the second numerical sequence into a second buffer area. Subsequently, the first numerical sequence is read from the first buffer area as a new quadrature component, and the second numerical sequence is read from the second buffer area as a new in-phase component. Finally, the new in-phase component and the new quadrature component are combined to form the swapped signal. This buffer swapping mechanism utilizes a double-buffered structure to ensure data flow continuity and is suitable for high real-time industrial environments.

[0087] Another swapping process is performed in the frequency domain. A Fast Fourier Transform (FFT) is performed on the original baseband signal to generate a frequency domain signal, which includes a sequence of in-phase components and a sequence of quadrature components. The values ​​of the in-phase and quadrature components are swapped to generate the swapped frequency domain signal, which is then converted back to the swapped signal using an Inverse Fast Fourier Transform (IFFT). Frequency domain processing leverages spectral characteristics to enhance signal transformation flexibility and improves processing reliability in factory environments with severe multipath interference. The swapping process also includes a sign inversion operation. For example, the first numerical sequence of the in-phase components is fed into the first data processing step to perform sign inversion, resulting in a first processed sequence. The second numerical sequence of the quadrature components is fed into the second data processing step and directly output as a new in-phase component. The first processed sequence is used as a new quadrature component, and the combination generates the swapped signal. Sign inversion introduces phase shift, increasing signal diversity.

[0088] The exchanged signals undergo transmission processing, first performing pulse shaping filtering to optimize spectral efficiency, and then employing a root-raised cosine filter to suppress inter-symbol interference. After shaping, the signal undergoes digital up-conversion, with a digital mixer shifting the baseband spectrum to the intermediate frequency (IF) spectrum to generate a digital IF signal. This digital IF signal is then converted into an analog transmit signal by a digital-to-analog converter for antenna radiation into the airspace. In industrial IoT applications, this processing chain adapts to channel characteristics, ensuring the integrity of control command transmission.

[0089] The receiver of the first wireless network captures wireless signals from the airspace as the received signal. The received signal may include mixed interference from either the first or second wireless network. The receiver performs analog-to-digital conversion on the received signal to generate a digital received signal, and then performs digital down-conversion to shift the intermediate frequency spectrum back to the baseband spectrum, generating the down-converted signal. The down-converted signal undergoes matched filtering, with the matched filter coefficients matching the pulse shaping filter at the transmitting end to maximize the signal-to-noise ratio, resulting in the signal to be inversely swapped. The inverse swapping process is the reverse of the swapping process. For example, it performs a Fast Fourier Transform on the received signal to generate a received frequency domain signal, swaps the values ​​of the in-phase and quadrature components in the received frequency domain, and then uses an inverse Fast Fourier Transform to generate the recovered signal. The inverse operation restores the original signal characteristics, ensuring that only the matched first network device can correctly demodulate it.

[0090] The mode switching function is implemented by receiving a mode switching command, including a mode identifier, from the network management entity. The mode identifier is parsed to obtain the current mode indication. If the current mode indication is mode one, the control signal processing path performs interchange and reverse interchange processing. In the transmission path, the baseband signal is guided to the interchange processing module via a multiplexer, and the processing result is sent to the transmit processing step. In the reception path, the matched-filtered signal is guided to the reverse interchange processing module via a multiplexer, and the recovered signal is output to the demodulation module. If the current mode indication is mode two, the signal processing path skips the interchange and reverse interchange processing and directly performs standard signal processing. Mode switching dynamically adapts to the network environment, improving device compatibility.

[0091] Configuration information encoding is completed at the transmitting end. The configuration information indicating the current mode is encoded as a bit sequence, which is carried in a reserved field of the physical layer frame structure. The transmitting end inserts the bit sequence into the frame header and transmits it with the signal. The receiving end decodes the bit sequence from the received frame structure, determines the current mode indication used by the transmitting end based on the decoding result, and sets the corresponding inverse swapping process. The encoding and decoding steps achieve synchronization between transmission and reception, ensuring matching of processing modes.

[0092] When the transmitting end of the first wireless network performs a swapping process and the receiving end performs a reverse swapping process, the devices in the first wireless network can communicate normally. If the transmitting end of the first wireless network performs a swapping process but the receiving end of the second wireless network does not perform a reverse swapping process, the second wireless network device cannot demodulate the signal from the first wireless network. Conversely, if the transmitting end of the second wireless network does not perform a swapping process but the receiving end of the first wireless network performs a reverse swapping process, the first wireless network device cannot demodulate the signal from the second wireless network.

[0093] In an Industrial Internet of Things (IIoT) environment, a first wireless network and a second wireless network often operate on the same frequency band, leading to signal interference. For example, in a smart manufacturing plant, the first wireless network transmits motion control commands for industrial robots, while the second wireless network supports data transmission from employee mobile devices. When robot control signals and data packets from the second wireless network overlap in the airspace, co-channel interference can cause command loss or delay, impacting production line efficiency. To address this issue, this invention proposes a wireless signal processing method that achieves network isolation by processing the in-phase and quadrature components of the baseband signal.

[0094] Embodiment 1 of this invention relates to a time-domain swapping process. At the transmitting end of the first wireless network, the original baseband signal is generated by a digital signal processor, including a first numerical sequence of in-phase components and a second numerical sequence of quadrature components; for example, these sequences are generated after robot control instructions are encoded. The transmitting end of the first wireless network writes the first numerical sequence into a first buffer area and the second numerical sequence into a second buffer area, using a double buffering mechanism to ensure continuous data flow. Subsequently, the first numerical sequence is read from the first buffer area as a new quadrature component, and the second numerical sequence is read from the second buffer area as a new in-phase component; the read operation is synchronized with the write pointer to avoid conflicts. The new in-phase component and the new quadrature component are combined to form a swapped signal, completing the swapping process. The swapped signal is pulse-shaping filtered to suppress inter-symbol interference, then digitally up-converted to an intermediate frequency, and transmitted by the antenna after digital-to-analog conversion. At the receiving end, the device of the first wireless network captures the wireless signal and performs analog-to-digital conversion to generate a digital received signal; digital down-conversion brings the signal back to baseband, and matched filtering yields the swapped signal to be reversed. The reverse swapping process performs the same buffer swapping: it separates the in-phase and quadrature sequences of the received signal, swaps them, and combines them into a recovered signal, which is then demodulated to obtain the communication data. When both the transceiver and receiver of the first wireless network enable this process, internal communication is normal; if the transmitter of the first wireless network swaps the signals but the receiver of the second wireless network does not perform the reverse swapping, the second wireless network device cannot demodulate the signal, thus achieving isolation.

[0095] Embodiment 2 of this invention employs frequency domain processing and introduces sign inversion. In the industrial robot control link of the first wireless network, the transmitting end performs a Fast Fourier Transform (FFT) on the original baseband signal to generate a frequency domain signal including a sequence of in-phase components and a sequence of quadrature components. The interchange process swaps the values ​​of these two sequences, for example, by iterating through each frequency point and swapping the array index; subsequently, an Inverse Fast Fourier Transform (IFFT) is performed on the swapped frequency domain signal to generate the swapped signal. Furthermore, sign inversion enhances isolation: the first numerical sequence of the in-phase components is fed into the first data processing process, and each sample value is inverted to obtain the first processed sequence; the second numerical sequence of the quadrature components is directly used as the new in-phase component, and the first processed sequence is used as the new quadrature component, combined and output. The transmission processing includes pulse shaping and up-conversion, while the receiving end performs corresponding inverse frequency domain swapping: the received signal is subjected to an IFFT, the frequency domain sequences are swapped, and then an inverse IFFT is performed to recover the signal. The mode switching function dynamically controls the processing path by parsing network commands; if the first mode is indicated, the transmitting path is directed to swapping processing, and the receiving path is directed to inverse swapping processing; the second mode skips these steps. Configuration information is encoded as a bit sequence carried in the physical layer frame, enabling synchronization mode settings for both the transmitter and receiver, thus enhancing flexibility. Frequency domain processing utilizes spectral characteristics to optimize signal integrity in multipath factory environments, while symbol inversion increases signal diversity, further reducing interference risks.

Claims

1. A method of wireless signal processing applied to a communication system comprising a first wireless network and a second wireless network, wherein the first wireless network and the second wireless network are two different wireless communication networks, characterized in that, include: Step 1: The transmitting end of the first wireless network acquires the original baseband signal, which is a time-domain signal and includes in-phase and quadrature components. Step 2: Based on the original baseband signal, perform a swapping process on the in-phase component and the quadrature component to generate a swapped signal; wherein, the swapping process includes time-domain swapping or frequency-domain swapping; Step 2, performing a swapping process on the in-phase component and the quadrature component to generate a swapped signal, includes: Based on the original baseband signal, the first numerical sequence of the in-phase component and the second numerical sequence of the quadrature component are separated; The first numerical sequence is sent to the first data processing process, and the second numerical sequence is sent to the second data processing process; In the first data processing process, the sign of the first numerical sequence is reversed by performing a two's complement operation on each sampled value to obtain the first processing sequence. The second numerical sequence is obtained from the second data processing procedure, and the second numerical sequence is used as a new in-phase component. The first processed sequence is used as a new orthogonal component; The new in-phase component is combined with the new quadrature component to generate an interchanged signal; the sign inversion introduces a phase shift. Step 3: Send the exchanged signals into the airspace; Step 4: The receiver of the first wireless network receives wireless signals from the airspace as received signals; Step 5: Perform inverse swapping processing on the received signal. The inverse swapping processing is the reverse of the swapping processing to obtain the recovered signal. Step 6: Demodulate the recovered signal to obtain communication data.

2. The wireless signal processing method according to claim 1, characterized in that, Step 2 involves swapping the in-phase component and the quadrature component to generate a swapped signal, including: Perform a fast Fourier transform on the original baseband signal to convert the original time-domain baseband signal into a frequency-domain signal, generating a frequency-domain signal, which includes a frequency-domain in-phase component sequence and a frequency-domain quadrature component sequence. The values ​​of the in-phase component sequence in the frequency domain are exchanged with the values ​​of the quadrature component sequence in the frequency domain to generate the exchanged frequency domain signal. Perform an inverse fast Fourier transform on the swapped frequency domain signal to convert the frequency domain signal back to the time domain signal, generating the swapped signal.

3. The wireless signal processing method according to claim 2, characterized in that, Step 5 involves performing an inverse swapping process on the received signal to obtain the recovered signal, including: Perform a Fast Fourier Transform on the received signal to convert the time-domain received signal into a received frequency-domain signal, generating a received frequency-domain signal, which includes a received frequency-domain in-phase component sequence and a received frequency-domain quadrature component sequence. The values ​​of the received frequency domain in-phase component sequence and the values ​​of the received frequency domain quadrature component sequence are swapped to generate the frequency domain signal after inverse swapping. Perform an inverse fast Fourier transform on the frequency domain signal after the inverse exchange to convert the frequency domain signal back to the time domain signal.

4. The wireless signal processing method according to claim 1, characterized in that, Step 3 also includes: The interchanged signal is transmitted and processed; the interchanged signal is a time-domain signal. Perform pulse shaping filtering on the interchanged signals to obtain the shaped signal; The shaped signal is digitally up-converted to shift the baseband spectrum to the intermediate frequency spectrum to generate a digital intermediate frequency signal; The digital intermediate frequency signal is converted from digital to analog to generate an analog transmission signal for transmission.

5. The wireless signal processing method according to claim 4, characterized in that, Step 5 also includes: The received signal is processed, and the received signal is an analog signal; The received signal is converted from analog to digital to generate a digital received signal, which is a time-domain signal; The digital received signal is digitally down-converted to shift the intermediate frequency spectrum back to the baseband spectrum, generating a down-converted signal, which is a time-domain signal. Perform matched filtering on the down-converted signal to obtain the inverted interchange signal, which is a time-domain signal; The reverse interchange process on the received signal is to perform the reverse interchange process on the signal to be reverse interchanged to obtain the recovered signal.

6. The wireless signal processing method according to claim 1, characterized in that, Also includes: Receive mode switching commands including mode identifiers; Parse the pattern identifier to obtain the current pattern indication; If the current mode indicates the first mode, then the control signal processing path performs the swapping process and the reverse swapping process; If the current mode indicates the second mode, the control signal processing path skips the swapping process and the reverse swapping process.

7. The wireless signal processing method according to claim 6, characterized in that, If the current mode indicates the first mode, the control signal processing path performs the swapping process and the reverse swapping process, including: In the transmission path, the baseband signal is directed to the swapping process, and the result of the swapping process is directed to the subsequent transmission processing steps; In the receiving path, the signal after receiving and processing is directed to the inverse interchange process, and the recovered signal obtained from the inverse interchange process is directed to the demodulation process.

8. The wireless signal processing method according to claim 7, characterized in that, Also includes: At the transmitting end, the configuration information indicating the current mode is encoded into a bit sequence, and the bit sequence is carried in the physical layer frame structure and transmitted. At the receiving end, the bit sequence is decoded from the received physical layer frame structure; The current mode indication used by the sending end is determined based on the decoded bit sequence; Based on the determined current mode indication, the corresponding reverse swapping process is set at the receiving end.

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