In wireless sensor networks (WSNs), traffic flow congestion can reduce network performance. We propose a congestion control method for WSNs that use a cache state with a dual threshold in the router buffer to control congestion. In addition, the congestion is controlled by the channel transmission state that is monitored by the queuing variation tendency and the transmission rate. Based on the active queue management mechanism, a dual threshold with the double index random early detection (DI-RED) model is established to improve network performance. We also present the congestion control algorithm of DI-RED model to ensure the perfect actualization. By solving the DI-RED model, a series of channel indicators is obtained, including packet loss rate, average queue length, delay and throughput. Simulation results show that the proposed DI-RED model is more stable and demonstrates better control, which can overcome the parameter sensitivity of the RED mechanism. The proposed model realises a reasonable tradeoff between network performance and packet dropping probability, which effectively avoids degraded network performance caused by pursuing a lower packet dropping probability. The results are important when selecting a congestion control mechanism and parameter settings for WSNs.

在无线传感器网络（WSN）中，流量拥塞会降低网络性能。我们为WSN提出了拥塞控制方法，该方法使用路由器缓冲区中具有双重阈值的缓存状态来控制拥塞。另外，通过由排队变化趋势和传输速率监视的信道传输状态来控制拥塞。基于主动队列管理机制，建立了具有双索引随机早期检测（DI-RED）模型的双阈值以提高网络性能。我们还提出了DI-RED模型的拥塞控制算法，以确保完美实现。通过求解DI-RED模型，获得了一系列信道指示符，包括丢包率，平均队列长度，延迟和吞吐量。仿真结果表明，所提出的DI-RED模型更稳定，控制效果更好，可以克服RED机制的参数敏感性。该模型实现了网络性能与丢包概率之间的合理权衡，有效避免了由于追求更低的丢包概率而导致的网络性能下降。在为WSN选择拥塞控制机制和参数设置时，结果非常重要。