为了提高LoRa通信系统节点的接入量，对LoRa通信系统的干扰及扩展性进行了详细分析。首先分析了LoRa相同扩频信道间和不同扩频信道间的干扰，得出相同扩频信道干扰严重的原因，以及不同扩频信道存在一定的干扰的情况，进而发现扩频信道间的码片间距越近干扰越严重；其次提出了一种LoRa不同扩频信道间的干扰消除算法，通过仿真验证了该算法能有效消除低扩频信道干扰的可行性；最后从理论上对LoRa原有调制解调算法进行了扩展性分析，结合LoRa技术的特点及干扰仿真结果得到LoRa技术新增扩频信道与相邻扩频信道的码片数之差大于等于128，并仿真验证了4条典型新增扩频信道的抗噪声性能、可行性，系统节点的可接入量能增加36.94%。
In order to improve the access capacity of LoRa communication system nodes, the interference and scalability of LoRa communication system are analyzed in detail. Firstly, this paper analyzes the interference between the same spread spectrum channel and the interference between different spread spectrum channels in LoRa, and obtains the reasons for the serious interference of the same spread spectrum channel and the certain interference of different spread spectrum channels. It is found that the closer the chip spacing between spread spectrum channels, the more serious the interference is. Secondly, an interference cancellation algorithm between different LoRa spread spectrum channels is proposed. Simulation results show that the algorithm can effectively eliminate the interference of low spread spectrum channels and is feasible. Finally, the expansibility of LoRa's original modulation and demodulation algorithm is analyzed through theory. Combined with the characteristics of LoRa technology and interference simulation results, it is concluded that the difference between the number of chips of LoRa's new spread spectrum channel and adjacent spread spectrum channel is greater than or equal to 128. The antinoise performance and feasibility of four typical new spread spectrum channels are verified by simulation, and the accessible capacity of system nodes can be increased by 36.94%.
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