A Coexistence Transmission Method for WIA-FA Network and Other Wireless Network Protocols

Abstract

The present invention provides a coexistence transmission method for a WIA-FA network and other wireless network protocols, which relates to the field of wireless communication technologies. Before the start of each transmission time slot of the WIA-FA network, a WIA-FA network device sends a CTS-to-Self frame based on the WLAN wireless network protocol standard and sends a coordinated busy tone for channel occupancy indication. The WIA-FA network device performs data transmission during the transmission time slot. After the end of the transmission time slot, a long time slot is reserved for other wireless network protocols to perform data transmission. After receiving the CTS-to-Self frame sent by the WIA-FA network device, the WLAN wireless network device actively backs off to send data, or actively backs off to send data after detecting the coordinated busy tone. The present invention can ensure the reliability and real-time performance of communication when the WIA-FA network coexists and communicates with other CSMA-based wireless protocols such as WLAN in the same frequency band.

Description

Technical Field

[0001] This application relates to the field of wireless communication technologies, and particularly to a coexistence transmission method for a WIA-FA network and other wireless network protocols. Background Art

[0002] WIA-FA (Wireless Industrial Automation - Fieldbus Access) is an industrial wireless network technology specifically developed for the high real-time and high reliability requirements of factory automation. At the data link layer, WIA-FA uses a superframe technology based on the time division multiple access (TDMA) mechanism for data transmission. The time is divided into multiple time slots, and each time slot is allocated to different devices for communication, thereby achieving efficient channel utilization and avoiding collisions.

[0003] However, when a WIA-FA network coexists and communicates with other wireless protocol networks such as WLAN on the same frequency band, it often faces channel competition and interference problems. Due to different communication protocols, the WIA-FA network does not listen to the channel state and perform relevant backoff actions when transmitting data in the preconfigured time slots, resulting in a large number of wireless data collisions in the air, affecting the reliability of communication. Although the WIA-FA network has relevant retransmission algorithms, increasing the number of retransmissions may not fully ensure communication reliability; second, it will reserve a large number of retransmission time slots, occupying a large amount of communication resources, increasing the polling period of data transmission, and reducing the real-time performance of network communication. Summary of the Invention

[0004] In view of this, the present invention provides a coexistence transmission method for a WIA-FA network and other wireless network protocols to ensure the reliability and real-time performance of communication when the WIA-FA network coexists and communicates with other CSMA mechanism-based wireless protocols such as WLAN on the same frequency band.

[0005] To this end, the present invention provides the following technical solutions:

[0006] On the one hand, the present invention discloses a coexistence transmission method for a WIA-FA network and other wireless network protocols, including:

[0007] Before the start of each transmission time slot of the WIA-FA network, a WIA-FA network device sends a CTS-to-Self frame based on other wireless network protocol standards;

[0008] The WIA-FA network device performs data transmission in the transmission time slot; during the period of waiting for the receiving device to reply with an ACK after the transmission of each data frame in the transmission time slot, a coordination busy tone for channel occupancy indication is sent; the coordination busy tone refers to the Gaussian white noise sent by the WIA-FA network device for occupying the channel;

[0009] After the end of the transmission time slot, a long time slot with a preset length is reserved for other wireless network protocols to perform data transmission; the reserved time slot with a preset length refers to reserving a period of time slice for device transmission in the WIA-FA network scheduling for other wireless protocol devices to perform data transmission.

[0010] Furthermore, the WIA-FA network device performs data transmission in the transmission time slot, including:

[0011] After the sending device finishes sending data, it continuously sends a segment of extended data, where the extended data is a segment of data randomly generated by the sending device; the duration of the extended data is less than the short inter-frame spacing time.

[0012] Furthermore, the WIA-FA network device performs data transmission in the transmission time slot, including:

[0013] When the WIA-FA network device is in the receiving state, the radio frequency end detects a wireless signal and directly ignores the signal with a strength less than the signal detection threshold of the radio frequency end without tracking and receiving it.

[0014] The WIA-FA network devices adjust the transmission power according to the signal strength of the received frames of both communication parties, thereby reducing the impact on the transmission of other wireless devices; among them, the adjustment of the transmission power includes: the receiving device adjusts its own device's transmission power by increasing or decreasing 2 dbm each time based on the signal strength of the wireless frame of the sending device received until it meets the signal strength in the wireless frames of the preset communication parties.

[0015] Furthermore, it further includes: the WIA-FA network devices adjust the signal detection threshold and the energy detection threshold according to the signal strength of the received frames of both communication parties.

[0016] Furthermore, the CTS-to-Self frame format includes: 2 bytes of frame control, 2 bytes of backoff time, 6 bytes of receiving workstation address, and 4 bytes of frame check sequence.

[0017] Furthermore, the length of the backoff time indicated in the CTS-to-Self frame is equal to the current time slot length value of the WIA-FA network.

[0018] Furthermore, the duration of the coordinated busy tone is 0 to 16 microseconds.

[0019] On the other hand, the present invention also discloses a coexistence transmission method for a WIA-FA network and other wireless network protocols, including:

[0020] After receiving the CTS-to-Self frame sent by the WIA-FA network device, other wireless network devices actively back off from sending data, or actively back off from sending data after detecting the coordination busy tone; the WIA-FA network device sends a CTS-to-Self frame based on other wireless network protocol standards before the start of each transmission time slot in the WIA-FA network, and sends a coordination busy tone for channel occupancy indication; the coordination busy tone refers to the Gaussian white noise sent by the WIA-FA network device for occupying the channel.

[0021] In another aspect, the present invention also discloses a wireless communication system, which includes a WIA-FA network device and other wireless network devices, and uses the coexistence transmission method of the WIA-FA network and other wireless network protocols as described above for data communication.

[0022] Further, the other wireless network devices include wireless network devices based on the CSMA mechanism.

[0023] Advantages and positive effects of the present invention:

[0024] (1) Improve channel utilization rate: By actively constructing the CTS-to-Self frame and the transmission of the "coordination busy tone", the TDMA network effectively avoids the channel competition between the TDMA network and the WLAN network, and improves the channel utilization rate.

[0025] (2) Solve the drawback that there is a lack of mutual negotiation mechanism for multi-protocols in the same environment for transmission: The original TDMA network immediately sends data when the time slot is triggered, which is not only easily interfered, but also more likely to interfere with the WiFi network transmitting long data frames.

[0026] (3) Improve the coexistence performance of multi-protocol networks: By actively constructing the CTS-to-Self frame and the transmission of the "coordination busy tone", the TDMA network obtains a relatively idle channel environment for itself, improving communication reliability; at the same time, negotiate to occupy the communication time of the WLAN network for the time slot length of the TDMA network, usually in the order of hundreds of microseconds. The transmission target of the WLAN network is large traffic and large bandwidth, and the delay of hundreds of microseconds can be ignored. Moreover, more WLAN service data frames can be aggregated during the channel idle waiting time, and long data frames can be transmitted in an interference-free environment when obtaining the channel occupancy opportunity, improving communication rate and reliability.

[0027] (4) Strong adaptability: The solution of the present invention can dynamically adjust the number and length of transmission time slots according to the environmental interference situation, and has good adaptability and flexibility.

[0028] (5) Based on the characteristics of the WIA-FA network, the present invention designs configurable signal detection and threshold presetting for data transmission between WIA-FA network devices. For example, appropriate energy detection threshold presetting is set according to the fixed distance between devices. When a signal with an energy preset less than its threshold is detected, it is directly discarded. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0030] Figure 1 It is a schematic diagram of a wireless communication system in an embodiment of the present invention;

[0031] Figure 2 It is a flowchart of a method for coexisting and transmitting between a WIA-FA network and other wireless network protocols in an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] In order to enable those skilled in the art to better understand the solution of the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0033] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above drawings are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0034] The present invention provides a method for coexisting and transmitting between a WIA-FA network and other wireless network protocols, which is applied to, for example Figure 1The wireless communication system shown includes WIA-FA network devices and other wireless network devices. The method in the present invention is oriented to industrial control and acquisition scenarios, and the data types transmitted are small data, high concurrency, and frequent transmission.

[0035] As Figure 2 shown, a method for coexisting and transmitting between a WIA-FA network and other wireless network protocols in an embodiment of the present invention is applied to WIA-FA network devices, and specifically includes the following steps:

[0036] S11. Send a CTS-to-Self frame based on other wireless network protocol standards before the start of each transmission time slot in the WIA-FA network;

[0037] Among them, other wireless networks are wireless protocol networks such as WLAN based on other CSMA mechanisms.

[0038] In specific implementation, the CTS-to-Self frame format is as follows:

[0039]

[0040] Among them, Frame Control is a very important part of the 802.11 wireless network protocol frame structure. It is located at the beginning of the frame and is used to define the frame type, subtype, protocol version, frame direction, and some control flags. The following are some key information of Frame Control:

[0041] Protocol Version: Bits 0-1 of the Frame Control field are used to specify the protocol version number. The current 802.11 standard uses version number 00, that is, 0.

[0042] Type: Bits 2-3 of the Frame Control field define the main type of the frame. Specifically: 00: Management Frame, 01: Control Frame, 10: Data Frame, 11: Reserved.

[0043] Subtype: Bits 4-7 of the Frame Control field define the subtype of the frame. Different main types have different subtypes. For example, for management frames, the subtype can be Association Request, AssociationResponse, Beacon, etc.

[0044] The Frame Control field is crucial for understanding the 802.11 frame structure as it determines the type and purpose of the frame, thereby affecting how the frame is processed. For example, control frames are mainly used to assist in the delivery of data frames. They can be used to supervise access to the wireless medium and provide reliability at the MAC layer. In practical applications, the Frame Control field enables network devices to identify and manage different types of frames, ensuring the effectiveness and efficiency of wireless communication.

[0045] RA (Receiving Station Address) is used to identify the intended recipient of the frame, i.e., the MAC address of the receiving station. This field is part of the 802.11 frame header and is very important for frame routing and identification.

[0046] FCS (Frame Check Sequence) is a cyclic redundancy check (CRC) value used to detect whether errors occur during frame transmission. It is usually located at the end of the Ethernet frame. FCS is a 32-bit value calculated by the sending device and appended to the end of the data frame. When the data frame arrives at the receiving device, the receiving device recalculates the CRC value using the same algorithm and compares it with the received FCS. If they match, it is considered that no error occurred during frame transmission; if they do not match, it is considered that an error may have occurred during frame transmission, and the receiving device can choose to discard this frame and may request the sending end to retransmit.

[0047] Duration (backoff time) is used to tell the receiving end and all other devices listening on the same channel how long the sending end expects to occupy the wireless medium. This helps to avoid collisions because other devices can decide whether to delay sending their own frames based on their own needs and the expected usage of the channel. The length of the backoff time indicated in the CTS-to-Self frame is equal to the current time slot length value of the WIA-FA network.

[0048] S12. Send data during the transmission time slot;

[0049] The WIA-FA network is based on a TDMA transmission scheduling mechanism. Each device in the communication system achieves strict time synchronization based on timestamps, and data transmission is based on microsecond-level time slot scheduling.

[0050] S13. During the transmission time slot, after each data frame is transmitted and waiting for the receiving device to reply with an ACK, the sending end sends a coordinated busy tone for channel occupancy indication;

[0051] Among them, the coordination busy tone refers to the Gaussian white noise sent by WIA-FA network devices to occupy the channel. Substantially, it is invalid data information. When other wireless network devices monitor that the channel resources are occupied, they can determine that the current channel is busy and automatically back off.

[0052] After receiving the CTS-to-Self frame, the WLAN device actively backs off to send data, or after detecting the "coordination busy tone", it actively backs off to send data. This ensures that when the WIA-FA network sends data, the surrounding WLAN devices suspend data transmission, avoiding co-channel interference.

[0053] S14. After the sending time slot ends, reserve a time slot of a preset length for other wireless network protocols to perform data transmission.

[0054] Among them, reserving a time slot of a preset length means that in the network scheduling of the WIA-FA network, reserve a time slice for devices in the non-WIA-FA network for other wireless protocol devices to perform data transmission. The length of the time slot ensures that one frame of data of other wireless protocols can be transmitted and interacted.

[0055] In another embodiment, in the WIA-FA network, the network device can configure the function of sending extended data; after the sending device sends data, it needs the receiving party to send an ACK confirmation; in order to prevent collisions in data transmission between different protocol networks, after the sending device finishes sending data, it can continuously send a period of extended data. The duration of the extended data (if it is a WLAN network, that is, the extended data is less than the SIFS (Short Interframe Space) time) is less than the time from when the receiving device finishes receiving the valid data to the time of responding with an ACK frame; other devices continuously monitor that the channel is busy and back off by themselves. Through this method, it can effectively avoid other protocol devices from interfering with each other during the time when the WIA-FA network device waits for the reply ACK frame and transmitting data, resulting in the failure of data transmission for both parties.

[0056] In another embodiment, the WIA-FA network device can continuously monitor the surrounding wireless environment signals, and at the same time, based on the signal strength values obtained from the frame transmission between communication devices, automatically adjust the transmission power and the signal detection threshold value and the energy detection threshold value; directly ignore the signals less than the signal detection threshold value and do not track them; adjust the transmission power according to the distance between WIA-FA network devices to reduce the mutual interference between network devices of different protocols.

[0057] Among them, adjusting the transmission power includes: the receiving device adjusts its own device's transmission power by increasing or decreasing 2 dbm each time based on the wireless frame signal strength received from the sending device until it meets the signal strength in the wireless frames of the preset communication parties.

[0058] For example, a WIA-FA network device detects other wireless network signals around it; when communicating between WIA-FA network devices, the signal strength received by device 1 from device 2 is -32 dBm, and the signal strength received by device 2 from device 1 is -35 dBm. Then, the transmission powers of device 1 and device 2 can be adjusted so that the signal strength of the communication between device 1 and device 2 is -55 dBm. At the same time, the energy detection threshold can be adjusted to (-75 dBm), and the signal monitoring threshold to (-65 dBm).

[0059] Device 1 and device 2 reduce their transmission powers to reduce the impact on other surrounding protocol networks. By increasing the energy detection threshold and the signal detection threshold, the impact of the surrounding networks on the communication of WIA-FA network devices is reduced.

[0060] In another embodiment, a coexistence transmission method for a WIA-FA network and other wireless network protocols, which is applied to other wireless network devices, specifically includes the following steps:

[0061] S21. After receiving a CTS-to-Self frame, other wireless network devices actively back off from sending data, or after detecting a "coordination busy tone", actively back off from sending data.

[0062] This method is for industrial control and acquisition scenarios. The data types transmitted have the characteristics of small data packets. The backoff time length indicated in the CTS-to-Self frame constructed by the TDMA network should not be greater than the time slot length (in the order of hundreds of microseconds), and the "coordination busy tone" is only restricted to 0 to 16 microseconds. After the transmission time slot ends, a long time slot is reserved for other CSMA networks such as WLAN to perform data transmission, without degrading the performance of other communication systems such as WLAN. It effectively avoids the competition and preemption between TDMA networks such as WIA-FA and WLAN networks, and enhances the coexistence communication performance.

[0063] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A coexistence transmission method for a WIA-FA network and other wireless network protocols, characterized in that, Including: The WIA-FA network device sends a CTS-to-Self frame based on other wireless network protocol standards before the start of each transmission time slot in the WIA-FA network; The WIA-FA network device conducts data transmission during the transmission time slot; during the period of waiting for the receiving device to reply with an ACK after the transmission of each data frame within the transmission time slot, a coordinated busy tone for channel occupancy indication is sent; the coordinated busy tone refers to the Gaussian white noise sent by the WIA-FA network device for occupying the channel; After the end of the sending time slot, a time slot with a preset length is reserved for other wireless network protocols to conduct data transmission; the reserved time slot with a preset length means that in the network scheduling of the WIA-FA network, a period of time slice for device transmission in the non-WIA-FA network is reserved for other wireless network devices to conduct data transmission; The other wireless network devices include wireless network devices based on the CSMA mechanism.

2. The coexistence transmission method of a WIA-FA network and other wireless network protocols according to claim 1, wherein The WIA-FA network device conducts data transmission during the transmission time slot, including: After the sending device finishes sending data, an extended data is continuously sent, and the extended data refers to a piece of data randomly generated by the sending device; the duration of the extended data is less than the short inter-frame interval time.

3. A coexistence transmission method for a WIA-FA network and other wireless network protocols according to claim 1, characterized in that, The WIA-FA network device conducts data transmission during the transmission time slot, including: When the WIA-FA network device is in the receiving state and the radio frequency end detects a wireless signal, signals with a strength less than the signal detection threshold value of the radio frequency end are directly ignored and not tracked for reception; The WIA-FA network devices adjust the transmission power according to the signal strength of the received frames between the communication parties, so as to reduce the impact on the transmission of other wireless devices; among them, the adjustment of the transmission power includes: the receiving device adjusts its own device's transmission power by increasing or decreasing 2 dbm each time based on the signal strength of the wireless frame of the sending device until it meets the signal strength in the wireless frames of the preset communication parties.

4. A coexistence transmission method for a WIA-FA network and other wireless network protocols according to claim 3, characterized in that, Also including: The WIA-FA network devices adjust the signal detection threshold value and the energy detection threshold value according to the signal strength of the received frames between the communication parties.

5. A coexistence transmission method for a WIA-FA network and other wireless network protocols according to claim 1, characterized in that The CTS-to-Self frame format includes: 2 bytes of frame control, 2 bytes of backoff time, 6 bytes of receiving workstation address, and 4 bytes of frame check sequence.

6. A coexistence transmission method for a WIA-FA network and other wireless network protocols according to claim 5, characterized in that, The length of the backoff time indicated in the CTS-to-Self frame is equal to the current time slot length value of the WIA-FA network.

7. A coexistence transmission method for a WIA-FA network and other wireless network protocols according to claim 1, characterized in that The duration of the coordinated busy tone is 0 to 16 microseconds.

8. A coexistence transmission method for a WIA-FA network and other wireless network protocols, characterized in that, Including: After receiving the CTS-to-Self frame sent by the WIA-FA network device, the other wireless network devices actively back off from sending data, or actively back off from sending data after detecting the coordinated busy tone; The WIA-FA network device sends a CTS-to-Self frame based on other wireless network protocol standards before the start of each transmission time slot in the WIA-FA network, and sends a coordinated busy tone for channel occupancy indication; the coordinated busy tone refers to the Gaussian white noise sent by the WIA-FA network device for occupying the channel; the other wireless network devices include wireless network devices based on the CSMA mechanism.

9. A wireless communication system, characterized in that, The wireless communication system includes WIA-FA network devices and other wireless network devices, and uses the WIA-FA network and other wireless network protocol coexistence transmission method according to any one of claims 1 to 8 for data communication.

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