We investigate the coexistence of massive and critical Internet of Things (IoT) services in the context of the unsourced multiple access (UMA) framework introduced by Polyanskiy (2017), where all users employ a common codebook and the receiver returns an unordered list of decoded codewords. This setup is suitably modified to introduce heterogeneous traffic. Specifically, to model the massive IoT service, a standard message originates independently from each IoT device as in the standard UMA setup. To model the critical IoT service, we assume the generation of alarm messages that are common for all devices. This setup requires a significant redefinition of the error events, i.e., misdetections and false positives. We further assume that the number of active users in each transmission attempt is random and unknown. We derive a random-coding achievability bound on the misdetection and false positive probabilities of both standard and alarm messages on the Gaussian multiple access channel. Using our bound, we demonstrate that orthogonal network slicing enables massive and critical IoT to coexist under the requirement of high energy efficiency. On the contrary, we show that nonorthogonal network slicing is energy inefficient due to the residual interference from the alarm signal when decoding the standard messages.

翻译：在Polyanskiy(2017年)推出的无源多重访问框架(UMA)背景下,我们调查了大规模和关键的事件互联网(IoT)服务的共存情况,在这个框架下,所有用户都使用一个共同的代码簿,接收者返回一个未排序的解码编码词列表。这个设置适当修改,以引入多种交通。具体地说,为了模拟巨大的 IoT 服务,一个标准信息从每个IoT 设备独立产生,就像UMA 标准设置一样。为了模拟关键的IoT 服务,我们假设生成了所有装置都常见的警报信息。这个设置需要大大重新定义错误事件,即错误检测错误和错误阳性。我们进一步假设,每次传输尝试中活动用户的数量是随机和未知的。我们从一个随机编码中得出一个连接错误检测和错误正面概率的信息,在Gausian 多重访问频道上,标准信号和警示信号的概率。我们用我们的绑定,我们展示了这个或多调网络使大规模和关键的IoT 信号能够大规模和关键的信号在高水平的能量干扰网络下共存。