LoRa, due to its advantage of long-range communication capability, is promising for Internet of Things (IoT) and space-air-ground communications. However, the conventional MAC protocol used with LoRa is classified as an Aloha-based algorithm, which leads to drastic decrease in throughput when a huge amount of end-devices try to access the network. To achieve stable and high throughput of LoRa, we propose a design to combine the distributed queueing (DQ) and in-band-full-duplex (IBFD) technologies. The usage of DQ mechanism is benefit for fast collision resolution, while the IBFD-enabled gateway helps to reduce the heavy control overhead of DQ. The designs of access procedure and frame structure are discussed in detail. The outage probability and average throughput are evaluated under imperfect self-interference cancelation. Also, a mathematical programming method is developed to optimize the spreading factor and code rate. Numerical results show that our proposal gains an extra enhancement of 1.83-fold in throughput.

LoRa由于具有远距离通信能力的优势，在物联网（IoT）和天空地通信方面大有可为。然而，与 LoRa 一起使用的传统 MAC 协议被归类为基于 Aloha 的算法，当大量终端设备尝试访问网络时，这会导致吞吐量急剧下降。为了实现 LoRa 的稳定和高吞吐量，我们提出了一种结合分布式排队 (DQ) 和带内全双工 (IBFD) 技术的设计。使用 DQ 机制有利于快速解决冲突，而启用 IBFD 的网关有助于减少 DQ 的繁重控制开销。详细讨论了接入流程和帧结构的设计。中断概率和平均吞吐量是在不完美的自干扰消除下评估的。还，开发了一种数学规划方法来优化扩频因子和码率。数值结果表明，我们的提议在吞吐量上获得了 1.83 倍的额外增强。