论文标题
基于赠款的访问协议中光谱效率，用户密度和能量的相互作用
The Interplay of Spectral Efficiency, User Density, and Energy in Grant-based Access Protocols
论文作者
论文摘要
我们采用基于赠款的访问权限，可为多个有效载荷的多个用户进行重新启动，尤其是在低频谱效率（SE）下。无线电资源在当时通过NOMA分配给$ t $插槽和频率尺寸，并衡量了非正交性$η$。重传存储在具有有限尺寸$ c _ {\ sf buf} $的接收器缓冲区中，并使用chase组合（CC）和增量冗余（IR）合并。我们确定了SE（位/rdoF）和用户密度$ j/n $的最佳缩放，对于给定数量的用户$ j $和blocklength $ n $，而snr（$ρ$）每位，即对总和结果的比率$ e_b/n_0 $，用于总和最佳制度，以及分析nose a nosise（fiter A nosise（fiter A），使用A nose（TIFIN）。将经典方案（无重传）与CC-NOMA，CC-SOMA和IR-homa策略中的CC-NOMA和SUM-rate最佳案例中的策略进行了对比，SE的数值结果表明，CC-Noma几乎在所有方案中都胜过其他方法，其他方法是其他方法。在总和最佳制度中，$ j/n $对$ e_b/n_0 $ a $ t $的量表以$ t $恶化，但从最少的降级到最少的，该方案的顺序如（i）经典，（ii）cc-oma，（ii）cc-oma，（iii）ir-soma和（iiv）ir-soma和（iv）cc-noma cc-noma，表现强大的cc-cc-cc-cc-nosa。对比$ρ$的锡型模型对比，基于CC的模型的$ J/N $的尺度提高了最佳状态，而在高$ρ$的情况下，CC-NOMA的缩放率由于较高的干扰而较差，并且CC-SOMA由于重新投入的结合而变得突出，因此变得突出。缩放结果适用于$η$，$ t $，$ c _ {\ sf buf} $和$ j $的范围内。所提出的分析框架为基于赠款的访问和特定的5G用例中的资源分配提供了见解，以进行大规模的URLLC上行链路访问。
We employ grant-based access with retransmissions for multiple users with small payloads, particularly at low spectral efficiency (SE). The radio resources are allocated via NOMA in the time into $T$ slots and frequency dimensions, with a measure of non-orthogonality $η$. Retransmissions are stored in a receiver buffer with a finite size $C_{\sf buf}$ and combined via HARQ, using Chase Combining (CC) and Incremental Redundancy (IR). We determine the best scaling for the SE (bits/rdof) and for the user density $J/n$, for a given number of users $J$ and a blocklength $n$, versus SNR ($ρ$) per bit, i.e., the ratio $E_b/N_0$, for the sum-rate optimal regime and when the interference is treated as noise (TIN), using a finite blocklength analysis. Contrasting the classical scheme (no retransmissions) with CC-NOMA, CC-OMA, and IR-OMA strategies in TIN and sum-rate optimal cases, the numerical results on the SE demonstrate that CC-NOMA outperforms, almost in all regimes, the other approaches. In the sum-rate optimal regime, the scalings of $J/n$ versus $E_b/N_0$ deteriorate with $T$, yet from the most degraded to the least, the ordering of the schemes is as (i) classical, (ii) CC-OMA, (iii) IR-OMA, and (iv) CC-NOMA, demonstrating the robustness of CC-NOMA. Contrasting TIN models at low $ρ$, the scalings of $J/n$ for CC-based models improve the best, whereas, at high $ρ$, the scaling of CC-NOMA is poor due to higher interference, and CC-OMA becomes prominent due to combining retransmissions and its reduced interference. The scaling results are applicable over a range of $η$, $T$, $C_{\sf buf}$, and $J$, at low received SNR. The proposed analytical framework provides insights into resource allocation in grant-based access and specific 5G use cases for massive URLLC uplink access.
