In this paper, we propose bit-interleaved multiple access (BIMA) to enable Internet-of-Things (IoT) networks where a massive connection is required with limited resource blocks. First, by providing a true power allocation (PA) constraint for conventional NOMA with practical constraints, we demonstrate that it cannot support massive connections. To this end, we propose BIMA where there are no strict PA constraints, unlike conventional NOMA, thus allowing a high number of devices. We provide a comprehensive analytical framework for BIMA for all key performance indicators (KPIs) (i.e., ergodic capacity [EC], outage probability [OP], and bit error rate [BER]). We evaluate Jain's fairness index and proportional fairness index in terms of all KPIs. Based on the extensive computer simulations, we reveal that BIMA outperforms conventional NOMA significantly, with a performance gain of up to 20-30dB. This performance gain becomes greater when more devices are supported. BIMA provides a full diversity order and enables the implementation of an arbitrary number of devices and modulation orders, which is crucial for IoT networks in dense areas. BIMA guarantees a fairness system where none of the devices gets a severe performance and the sum-rate is shared in a fair manner among devices by guarantying QoS satisfaction. Finally, we provide an intense complexity and latency analysis and demonstrate that BIMA provides lower latency compared to conventional NOMA since it allows parallel computing at the receivers and no iterative operations are required. We show that BIMA reduces latency by up to 350\% for specific devices and 170\% on average.

翻译：本文提出比特交织多址接入（BIMA）技术，以支持在有限资源块下实现大规模连接的物联网（IoT）网络。首先，通过对传统非正交多址接入（NOMA）施加实际约束条件下的真实功率分配（PA）限制，我们证明其无法支撑大规模连接。为此，我们提出BIMA技术，该技术不同于传统NOMA，无严格功率分配约束，从而允许支持大量设备。我们针对BIMA的所有关键性能指标（KPI），即遍历容量（EC）、中断概率（OP）和误比特率（BER），建立了全面的分析框架。同时，基于所有KPI评估了Jain公平性指数和比例公平性指数。通过大量计算机仿真，我们发现BIMA显著优于传统NOMA，性能增益可达20-30dB。当支持更多设备时，该性能增益将进一步扩大。BIMA能够提供满分集阶数，并支持任意数量设备及调制阶数的实现，这对于密集区域物联网网络至关重要。BIMA保证了系统公平性，避免任何设备遭受严重性能损失，并通过保障服务质量（QoS）要求，使总速率在设备间公平分配。最后，我们进行了深入的复杂度与时延分析，证明由于接收端支持并行计算且无需迭代操作，BIMA相比传统NOMA具有更低的时延。实验表明，BIMA可将特定设备的时延降低高达350%，平均降低170%。