A regional ad hoc network wireless LoRa module relay method

Abstract

The invention discloses a regional self-organizing network wireless LoRa module relay algorithm, which divides the working frequency of the LoRa module into a plurality of sub-channels with an interval of 1MHz, closes the receiving channel N after completing the reception of a data packet, changes the level of the MD0 and MD1 pins of the LoRa module, opens the sending channel M of the module and forwards the data packet, wherein M≠N. The invention solves the problem that the LoRa module does not support the relay function in the prior art.

Description

Technical Field

[0001] The invention belongs to the field of relay algorithms, and in particular relates to a regional ad hoc network wireless LoRa module relay method. Background Art

[0002] LoRa is the physical layer or wireless modulation for creating long-distance communication connections. Compared with traditional FSK technology, LoRa technology based on CSS modulation technology (Chirp Spread Spectrum) can greatly increase the communication range. In addition, CSS technology has been widely used in military and space communications for decades, and has the characteristics of long transmission distance and strong anti-interference.

[0003] Regional self-organizing network geological disaster monitoring requires the use of LoRa modules because the data collected by the collection nodes need to be transmitted over long distances. However, in many cases, due to the large monitoring range, the transmission range of a LoRa module is difficult to cover the collection nodes in a large range, but the existing wireless LoRa modules only support the LoRaWAN protocol and do not support the relay function. Therefore, how to make the LoRa module have a relay function is crucial. Summary of the invention

[0004] The technical problem to be solved by the present invention is: in view of the problem that the LoRa module in the prior art does not support the relay function, the present invention provides a regional ad hoc network wireless LoRa module relay method.

[0005] The technical solution of the present invention is: a regional ad hoc network wireless LoRa module relay method, which divides the operating frequency of the LoRa module into several sub-channels with an interval of 1MHz. After completing the reception of a data packet, the receiving channel N is closed, the levels of the MD0 and MD1 pins of the LoRa module are changed, the sending channel M of the module is opened and the data packet is forwarded, wherein M≠N.

[0006] Furthermore, the subchannel includes n receiving subchannels and n sending subchannels, the operating frequencies of the n receiving subchannels are different, the sending subchannels correspond to the receiving subchannels one by one, and each corresponding sending subchannel has the same operating frequency as the receiving subchannel. Each time the n receiving subchannels receive a data packet signal of the corresponding working frequency of the same LoRa module, the LoRa module converts each data packet into a binary code, and takes the value with the highest frequency of occurrence of the digit corresponding to the binary code of each data packet as the value of this digit, places all digits with the highest probability of occurrence in the corresponding digits to form the optimal data packet received by this LoRa module, and sends the optimal data packet through the n sending subchannels of this LoRa module.

[0007] Furthermore, each data packet has a bit error rate verification area, which is a specified binary sequence. After each receiving sub-channel receives the data packet, it checks the bit error rate verification area. If the bit error rate of the bit error rate verification area is greater than the set value, the data packet received by the corresponding receiving sub-channel is discarded, and the discarded data packet does not participate in the calculation of the optimal data packet.

[0008] Furthermore, when the number of discarded data packets exceeds a set value, the receiving channel of the discarded data packets is made to receive data packets sent by other LoRa modules, where the other LoRa modules are the source LoRa modules of the data packets received by the receiving channel of the data packets that are not discarded. The bit error rate verification areas of all data packets sent by other LoRa modules are verified, and data packets whose bit error rates in the bit error rate verification area are less than the set value are retained. If the number of data packets is still less than the set value, the corresponding receiving channel continues to replace the LoRa module that sends the data packets until the number of data packets exceeds the set value.

[0009] Compared with the prior art, the present invention has the following beneficial effects:

[0010] The present invention divides the operating frequency of the LoRa wireless communication module into several different channels, and uses different channels for sending and receiving data, so that the LoRa wireless communication module supports the relay function. At the same time, since different channels are used for data sending and receiving, there is no need for precise timing control, and the problems of channel blocking, data confusion and data packet loss are avoided. DETAILED DESCRIPTION

[0011] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in combination with the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Generally, the components of the embodiments of the present application described and shown here can be arranged and designed in various different configurations.

[0012] Therefore, the detailed description of the embodiments of the present application is not intended to limit the scope of the present application for protection, but merely represents selected embodiments of the present application. All other embodiments obtained by ordinary technicians in the field without creative work based on the embodiments in the present application are within the scope of protection of the present application.

[0013] Implementation Example 1:

[0014] In order to enable the relay node to have a relay function while avoiding channel blocking, data confusion and data packet loss, a regional ad hoc network wireless LoRa module relay method is provided in this embodiment, in which the operating frequency of the relay node is divided into several sub-channels with an interval of 1MHz. After completing the reception of a data packet, the receiving channel N is closed, the levels of the MD0 and MD1 pins of the relay node are changed, the sending channel M of the module is opened and the data packet is forwarded, where M≠N.

[0015] In order to avoid complex time slot control, this method uses different sub-channels with the same bandwidth (1MHz) to receive and send data packets respectively. After completing the reception of a data packet, the receiving channel N is closed. The system changes the level of the MD0 and MD1 pins of the wireless LoRa module to open the module's sending channel M (M≠N) and forward the data packet. Since different channels are used for transmission and reception, precise timing control is not required, thus avoiding channel blocking, data confusion, data packet loss and other problems. Through the above method, the system realizes the relay function of the wireless LoRa module based on the LoRaWAN protocol, thereby constructing a star-line network topology with relays.

[0016] In order to avoid the increase of bit error rate caused by electromagnetic interference and other factors in the process of forwarding data packets by the LoRa module, especially the increase of bit error rate after multiple forwardings, in this embodiment, further, the subchannel includes n receiving subchannels and n sending subchannels, the operating frequencies of the n receiving subchannels are different, the sending subchannels correspond to the receiving subchannels one by one, and each corresponding sending subchannel has the same operating frequency as the receiving subchannel. After each n receiving subchannel receives the data packet signal of the corresponding working frequency of the same LoRa module, the LoRa module converts each data packet into a binary code, and takes the value with the highest frequency of occurrence of the digit corresponding to the binary code of each data packet as the value of this digit, places the values ​​with the highest probability of occurrence of all digits in the corresponding digits to form the optimal data packet received by this LoRa module, and sends the optimal data packet through the n sending subchannels of this LoRa module.

[0017] The principle is: the error codes generated by data packets are random, so when the number of receiving channels is large enough, the randomly generated error codes can be filtered out by increasing the number of samples, thereby reducing the bit error rate. On the other hand, due to different operating frequencies, the bit error rate of data packets in the face of electromagnetic interference is also different for each operating frequency, and the error codes can also be filtered out through multiple operating frequencies, thereby reducing the bit error rate.

[0018] A specific frequency has a high overall bit error rate due to a long distance or severe interference. At this time, if the data packet received at this working frequency is also used to participate in the calculation of the optimal data packet, it will not only be ineffective, but will increase the noise of the data packet. In order to avoid this problem, in this embodiment, further, each data packet has a bit error rate verification area, and the bit error rate verification area is a string of specified binary sequences. After each receiving sub-channel receives the data packet, the bit error rate verification area is checked. If the bit error rate of the bit error rate verification area is greater than the set value, the data packet received by the corresponding receiving sub-channel is discarded, and the discarded data packet does not participate in the calculation of the optimal data packet.

[0019] If too many data packets are discarded, the number of data packets participating in the optimal data packet calculation will be too small, making the error code filtering effect unobvious. In order to solve this problem, in this embodiment, when the number of discarded data packets exceeds the set value, the receiving channel of the discarded data packets is allowed to receive data packets sent by other LoRa modules. The other LoRa modules refer to the source LoRa modules of the data packets received by the receiving channels of the data packets that have not been discarded. The bit error rate verification areas of all data packets sent by other LoRa modules are verified, and the data packets whose bit error rates in the bit error rate verification areas are less than the set value are retained. If the number of data packets is still less than the set value, the corresponding receiving channel continues to replace the LoRa module that sends the data packets until the number of data packets exceeds the set value.

[0020] Here, on the one hand, by replacing the LoRa module that sends the data packet, the number of modules participating in the optimal data packet calculation is increased, so that the error code filtering effect is improved; on the other hand, the problem of the system being unable to operate due to the high bit error rate caused by the failure of a single LoRa module that sends a data packet can be avoided.

[0021] The above-mentioned embodiments only express the preferred implementation modes of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present invention. It should be pointed out that, for those skilled in the art, several modifications, improvements and substitutions can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention.

Claims

1. A regional ad hoc network wireless LoRa module relay method, characterized in that: The operating frequency of the LoRa module is divided into several sub-channels with an interval of 1MHz. After completing the reception of a data packet, the receiving channel N is closed, and the levels of the MD0 and MD1 pins of the LoRa module are changed to open the module's sending channel M and forward the data packet, where M≠N; The subchannels include n receiving subchannels and n sending subchannels, the operating frequencies of the n receiving subchannels are different, the sending subchannels correspond to the receiving subchannels one by one, and the operating frequency of each corresponding sending subchannel is the same as that of the receiving subchannel. Each time the n receiving subchannels receive a data packet signal of the corresponding working frequency of the same LoRa module, the LoRa module converts each data packet into a binary code, and takes the value with the highest frequency of occurrence of the digit corresponding to the binary code of each data packet as the value of the digit, places all the digits with the highest probability of occurrence in the corresponding digits to form the optimal data packet received by the LoRa module, and sends the optimal data packet through the n sending subchannels of the LoRa module.

2. According to claim 1 regional ad hoc network wireless LoRa module relay method, it is characterized in that, Each data packet has a bit error rate verification area, which is a specified binary sequence. After each receiving sub-channel receives the data packet, it checks the bit error rate verification area. If the bit error rate of the bit error rate verification area is greater than the set value, the data packet received by the corresponding receiving sub-channel is discarded, and the discarded data packet does not participate in the calculation of the optimal data packet.

3. According to claim 2 regional ad hoc network wireless LoRa module relay method, it is characterized in that, When the number of discarded data packets exceeds the set value, the receiving channel of the discarded data packets is made to receive data packets sent by other LoRa modules, where the other LoRa modules are the source LoRa modules of the data packets received by the receiving channel of the data packets that are not discarded. The bit error rate verification areas of all data packets sent by other LoRa modules are verified, and data packets whose bit error rates in the bit error rate verification area are less than the set value are retained. If the number of data packets is still less than the set value, the corresponding receiving channel continues to replace the LoRa module that sends the data packets until the number of data packets exceeds the set value.