Coexistence transmission method for WIA-FA network and other wireless network protocols

Abstract

The invention provides a coexistence transmission method for a WIA-FA network and other wireless network protocols, and relates to the technical field of wireless communication, WIA-FA network equipment sends a CTS-to-Self frame based on a WLAN wireless network protocol standard before each transmission time slot of the WIA-FA network starts, and sends a coordination busy tone for channel occupation indication; the WIA-FA network equipment performs data transmission in the transmission time slot; and after the sending time slot is finished, reserving a long time slot for other wireless network protocols to carry out data transmission. And the WLAN wireless network equipment actively withdraws to send data after receiving the CTS-to-Self frame sent by the WIA-FA network equipment, or actively withdraws to send data after detecting a coordination busy tone. According to the invention, the reliability and real-time performance of communication can be ensured when a WIA-FA network and other wireless protocols based on a CSMA mechanism, such as a WLAN, coexist and communicate on the same frequency band.

Description

Technical Field

[0001] The present application relates to the field of wireless communication technology, and in particular to a method for transmitting a WIA-FA network coexisting with other wireless network protocols. Background Art

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

[0003] However, when WIA-FA networks coexist and communicate with other wireless protocol networks such as WLAN on the same frequency band, they often face channel competition and interference problems. Due to different communication protocols, WIA-FA networks do not monitor the channel status and perform relevant backoff actions during data transmission in pre-configured time slots, resulting in a large amount of wireless data collision in the air, affecting the reliability of communication. Although the WIA-FA network has a relevant retransmission algorithm, increasing the number of retransmissions may not completely ensure communication reliability; secondly, it will reserve a large number of retransmission time slots, occupy a large amount of communication resources, increase the polling cycle of data transmission, and reduce the real-time performance of network communication. Summary of the invention

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

[0005] To this end, the present invention provides the following technical solutions: In one aspect, the present invention discloses a WIA-FA network and other wireless network protocols coexisting transmission method, comprising: 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 performs data transmission in the transmission time slot; during the period of waiting for the receiving device to reply ACK after each data frame transmission is completed in the transmission time slot, a coordination busy tone for channel occupation indication is sent; the coordination busy tone refers to the Gaussian white noise sent by the WIA-FA network device to occupy the channel; After the sending time slot ends, a long time slot of a preset length is reserved for data transmission by other wireless network protocols; the time slot of the preset length reserved means that in the network scheduling of the WIA-FA network, a transmission time slice of a device in a non-WIA-FA network is reserved for data transmission by other wireless protocol devices.

[0006] Furthermore, the WIA-FA network device performs data transmission in the transmission time slot, including: After the sending device completes sending data, it continues to send a section of extended data, where the extended data refers to a section of data randomly generated by the sending device; the duration of the extended data is less than the short inter-frame interval.

[0007] Furthermore, the WIA-FA network device performs data transmission in the transmission time slot, including: When the WIA-FA network device is in the receiving state, the wireless radio frequency end detects the wireless signal and directly ignores the signal that is smaller than the signal detection threshold value of the radio frequency end, and does not perform tracking reception; The WIA-FA network devices adjust the transmission power according to the signal strength of the received frames of the communicating parties, thereby reducing the impact on the transmission of other wireless devices; wherein, the said adjustment of the transmission power includes: the receiving device adjusts the transmission power of its own device by 2dbm each time based on the signal strength of the wireless frame received from the sending device, until it meets the preset signal strength in the wireless frame of the communicating parties.

[0008] Furthermore, the method further includes: adjusting a signal detection threshold value and an energy detection threshold value between WIA-FA network devices according to signal strengths of frames received by both communicating parties.

[0009] 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.

[0010] Further, the backoff time length indicated in the CTS-to-Self frame is equal to the current time slot length value of the WIA-FA network.

[0011] Furthermore, the duration of the coordinated busy tone is 0 to 16 microseconds.

[0012] In another aspect, the present invention further discloses a WIA-FA network and other wireless network protocols coexisting transmission method, comprising: Other wireless network devices actively back off from sending data after receiving the CTS-to-Self frame sent by the WIA-FA network device, 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 of the WIA-FA network, and sends a coordination busy tone for channel occupancy indication; the coordination busy tone refers to Gaussian white noise sent by the WIA-FA network device to occupy the channel.

[0013] In another aspect, the present invention further discloses a wireless communication system, which includes a WIA-FA network device and other wireless network devices, and uses the above-mentioned WIA-FA network and other wireless network protocol coexistence transmission method for data communication.

[0014] Furthermore, the other wireless network devices include wireless network devices based on the CSMA mechanism.

[0015] Advantages and positive effects of the present invention: (1) Improving channel utilization: The TDMA network actively constructs CTS-to-Self frames and sends "coordinated busy tones", effectively avoiding channel competition between the TDMA network and the WLAN network and improving channel utilization.

[0016] (2) It solves the problem of lack of mutual negotiation mechanism when multiple protocols are transmitted in the same environment: the original TDMA network sends data immediately when the time slot is triggered, which is not only easy to be interfered with, but also more likely to interfere with the WiFi network that transmits long data frames.

[0017] (3) Improving the coexistence performance of multi-protocol networks: The TDMA network actively constructs CTS-to-Self frames and sends "coordinated busy tones" to allow itself to obtain a relatively idle channel environment and improve communication reliability. At the same time, the communication time for negotiating the occupation of the WLAN network is the length of the TDMA network's time slot, which is usually in the order of hundreds of microseconds. The WLAN network transmission target is large traffic and large bandwidth, and the delay of hundreds of microseconds can be ignored. In addition, more WLAN service data frames can be aggregated during the channel idle waiting time. When the channel occupation opportunity is obtained, long data frames can be transmitted in an interference-free environment, thereby improving communication rate and reliability.

[0018] (4) Strong adaptability: The solution of the present invention can dynamically adjust the number and length of transmission time slots according to environmental interference conditions, and has good adaptability and flexibility.

[0019] (5) Based on the characteristics of the WIA-FA network, the present invention designs a configurable signal detection and capability detection threshold preset for data transmission between WIA-FA network devices. For example, a suitable energy detection threshold preset is set according to a fixed distance between devices. When a signal with an energy preset smaller than the threshold is detected, it is directly discarded. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0021] Figure 1 A schematic diagram of a wireless communication system in an embodiment of the present invention; Figure 2 The present invention is a flowchart of a WIA-FA network and other wireless network protocols coexistence transmission method. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0023] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0024] The present invention provides a WIA-FA network and other wireless network protocols coexistence transmission method, which is applied to Figure 1The wireless communication system shown includes WIA-FA network equipment and other wireless network equipment. The method in the present invention is oriented to industrial control and acquisition scenarios, and the data type transmitted is small data, high concurrency, and frequent transmission.

[0025] like Figure 2 As shown, a WIA-FA network and other wireless network protocols coexistence transmission method in an embodiment of the present invention is applied to a WIA-FA network device, and specifically includes the following steps: S11, sending a CTS-to-Self frame based on other wireless network protocol standards before the start of each transmission time slot of the WIA-FA network; The other wireless networks are other wireless protocol networks based on the CSMA mechanism, such as WLAN.

[0026] In specific implementation, the CTS-to-Self frame format is as follows:

[0027] 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 is some key information of Frame Control: 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, which is 0.

[0028] Frame 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.

[0029] Subtype: Bits 4-7 of the Frame Control field define the subtype of the frame. Different main types have different subtypes. For example, for a management frame, the subtype can be Association Request, Association Response, Beacon, etc.

[0030] The Frame Control field is crucial to understanding the 802.11 frame structure because it determines the type and purpose of the frame, which affects 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 level. 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 communications.

[0031] RA (Receiving Station Address) is used to identify the destination of the frame, that is, 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.

[0032] FCS (Frame Check Sequence) is a cyclic redundancy check (CRC) value used to detect whether errors occurred during the transmission of a frame. It is usually located at the end of an Ethernet frame. FCS is a 32-bit value calculated by the sending device and attached 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 the two match, it is considered that no error occurred during the transmission of the frame; if they do not match, it is considered that an error may have occurred during the transmission of the frame. The receiving device can choose to discard the frame and may request the sender to retransmit it.

[0033] Duration (backoff time) is used to tell the receiver and all other devices listening to the same channel how long the transmitter expects to occupy the wireless medium. This helps avoid conflicts because other devices can decide whether to delay sending their frames based on their needs and the expected use 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.

[0034] S12, sending data in the transmission time slot; The WIA-FA network is based on the TDMA transmission scheduling mechanism. Each device in the communication system implements strict time synchronization based on timestamps, and data transmission is based on microsecond-level time slot scheduling.

[0035] S13, in the transmission time slot, after each data frame transmission is completed and while waiting for the receiving device to reply ACK, the transmitting end sends a coordination busy tone for channel occupancy indication; The coordinated busy tone refers to the Gaussian white noise sent by the WIA-FA network device to occupy the channel, which is essentially 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.

[0036] After receiving the CTS-to-Self frame, the WLAN device actively backs off sending data, or actively backs off sending data after detecting the "coordination busy tone". This ensures that the surrounding WLAN devices suspend data transmission when the WIA-FA network sends data, avoiding co-channel interference.

[0037] S14. After the sending time slot ends, a time slot of a preset length is reserved for data transmission using other wireless network protocols.

[0038] Among them, reserving a time slot of a preset length means reserving a transmission time slice of a device in a non-WIA-FA network in the network scheduling of the WIA-FA network for other wireless protocol devices to transmit data. The time slot length ensures that one frame of data of other wireless protocols can be transmitted and interacted.

[0039] In another embodiment, in a WIA-FA network, the network device can be configured to send extended data function; after the sending device sends data, the receiving party needs to send ACK confirmation; in order to prevent data transmission collision between different protocol networks, after the sending device completes data transmission, it can continue to send a section of extended data, and the duration of the extended data (if it is a WLAN network, that is, the extended data is less than SIFS (Short Interframe Space) time) is less than the time from the receiving device receiving the valid data to responding to the ACK frame; other devices continue to monitor that the channel is busy and retreat on their own. Through this method, other protocol devices can be effectively prevented from transmitting data while the WIA-FA network device is waiting for the reply ACK frame, causing mutual interference, resulting in data transmission failure on both sides.

[0040] In another embodiment, the WIA-FA network device can monitor the surrounding wireless environment signals in real time, and automatically adjust the transmission power, signal detection threshold value and energy detection threshold value based on the signal strength value obtained by frame transmission between communication devices; 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 mutual interference between network devices with different protocols.

[0041] The adjusting of the transmission power includes: the receiving device adjusts the transmission power of its own device by 2dbm each time based on the wireless frame signal strength received from the transmitting device, until it meets the preset signal strength in the wireless frame of the two communicating parties.

[0042] For example, a WIA-FA network device monitors other wireless network signals around it; when the WIA-FA network devices communicate, the signal strength of device 1 receiving device 2 is -32dBm, and the signal strength of device 2 receiving device 1 is -35dBm. Then the transmission power of device 1 and device 2 can be adjusted to make the signal strength of device 1 and device 2 communication at -55dBm. At the same time, the energy detection threshold value can be adjusted to (-75dBm) and the signal monitoring threshold value can be (-65dBm).

[0043] Device 1 and Device 2 reduce the transmission power to reduce the impact on other protocol networks around them. By increasing the energy detection threshold and signal detection threshold, the impact of surrounding networks on the communication of WIA-FA network devices is reduced.

[0044] In another embodiment, a WIA-FA network and other wireless network protocols coexistence transmission method is applied to other wireless network devices, specifically including the following steps: S21. Other wireless network devices actively back off from sending data after receiving the CTS-to-Self frame, or actively back off from sending data after detecting a "coordination busy tone".

[0045] This method is aimed at industrial control and acquisition scenarios. The data type transmitted has the characteristics of small data packets. The backoff time indicated in the CTS-to-Self frame constructed by the TDMA network should not be longer than the time slot length (hundreds of microseconds), and the "coordinated busy tone" is limited to 0~16 microseconds. After the sending time slot ends, a long time slot is reserved for data transmission in other CSMA networks such as WLAN, without reducing the performance of other communication systems such as WLAN. It effectively avoids competition and preemption between TDMA networks such as WIA-FA and WLAN networks, and enhances the coexistence communication performance.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A WIA-FA network and other wireless network protocols coexistence transmission method, characterized in that: include: 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 performs data transmission in the transmission time slot; during the period of waiting for the receiving device to reply ACK after each data frame transmission is completed in the transmission time slot, a coordination busy tone for channel occupation indication is sent; the coordination busy tone refers to the Gaussian white noise sent by the WIA-FA network device to occupy the channel; After the sending time slot ends, a time slot of preset length is reserved for data transmission by other wireless network protocols; the time slot of preset length reserved means that in the network scheduling of the WIA-FA network, a transmission time slice of a device in a non-WIA-FA network is reserved for data transmission by other wireless protocol devices.

2. The coexistence transmission method of a WIA-FA network and other wireless network protocols according to claim 1, characterized in that: WIA-FA network devices transmit data in the transmission time slot, including: After the sending device completes sending data, it continues to send a section of extended data, where the extended data refers to a section of data randomly generated by the sending device; the duration of the extended data is less than the short inter-frame interval.

3. The coexistence transmission method of a WIA-FA network and other wireless network protocols according to claim 1, characterized in that: WIA-FA network devices transmit data in the transmission time slot, including: When the WIA-FA network device is in the receiving state, the wireless radio frequency end detects the wireless signal and directly ignores the signal that is smaller than the signal detection threshold value of the radio frequency end, and does not perform tracking reception; The WIA-FA network devices adjust the transmission power according to the signal strength of the received frames of the communicating parties, thereby reducing the impact on the transmission of other wireless devices; wherein, the said adjustment of the transmission power includes: the receiving device adjusts the transmission power of its own device by 2dbm each time based on the signal strength of the wireless frame received from the sending device, until it meets the preset signal strength in the wireless frame of the communicating parties.

4. The coexistence transmission method of a WIA-FA network and other wireless network protocols according to claim 3, characterized in that: Also includes: The WIA-FA network devices adjust the signal detection threshold and energy detection threshold according to the signal strength of the frames received by both communicating parties.

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

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

8. A WIA-FA network and other wireless network protocols coexistence transmission method, characterized in that: include: Other wireless network devices actively back off sending data after receiving the CTS-to-Self frame sent by the WIA-FA network device, or actively back off 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 each transmission time slot of the WIA-FA network starts, and sends a coordination busy tone for channel occupancy indication; the coordination busy tone refers to Gaussian white noise sent by the WIA-FA network device to occupy the channel.

9. A wireless communication system, characterized in that: The wireless communication system includes WIA-FA network equipment and other wireless network equipment, and uses the coexistence transmission method of the WIA-FA network and other wireless network protocols as described in any one of claims 1 to 8 to perform data communication.

10. The wireless communication system according to claim 9, characterized in that: The other wireless network devices include wireless network devices based on the CSMA mechanism.

Images