To support ultra-reliable and low-latency services for mission-critical applications, transmissions are usually carried via short blocklength codes, i.e., in the so-called finite blocklength (FBL) regime. Different from the infinite blocklength regime where transmissions are assumed to be arbitrarily reliable at the Shannon's capacity, the reliability and capacity performances of an FBL transmission are impacted by the coding blocklength. The relationship among reliability, coding rate, blocklength and channel quality has recently been characterized in the literature, considering the FBL performance model. In this paper, we follow this model, and prove the joint convexity of the FBL error probability with respect to blocklength and transmit power within a region of interest, as a key enabler for designing systems to achieve globally optimal performance levels. Moreover, we apply the joint convexity to general use cases and efficiently solve the joint optimization problem in the setting with multiple users. We also extend the applicability of the proposed approach by proving that the joint convexity still holds in fading channels, as well as in relaying networks. Via simulations, we validate our analytical results and demonstrate the advantage of leveraging the joint convexity compared to other commonly-applied approaches.
翻译:为支持对任务至关重要的应用程序的超可靠和低长服务,传输通常通过短长代码,即所谓的有限区长(FBL)制度进行,与假定对香农能力而言传输是任意可靠的无限区长制度不同,FBL传输的可靠性和能力性能受到编织区长的影响。考虑到FBL的性能模式,考虑到FBL的性能模式,可靠性、编码率、区长和频道质量之间的关系最近在文献中已有特征。在本文件中,我们遵循这一模式,并证明FBL在区块长和电源传输方面的联合误差概率,作为设计系统以达到全球最佳性能水平的关键使能。此外,我们将联合连接性适用于一般使用的案件,并有效解决在环境中与多个用户的联合优化问题。我们还扩大了拟议方法的可适用性,证明联合调合性仍然停留在淡化的渠道中,以及在中继网络中。我们验证了联合分析结果并展示了其他优势,共同利用其他优势。