School of Electronic and Electrical Engineering, Kyungpook National University, Daegu 41566, Korea.
Sensors (Basel). 2022 May 10;22(10):3609. doi: 10.3390/s22103609.
The millimeter-wave (mmWave) band, which can provide data rates of multi-gigabits per second, could play a major role in achieving the throughput goals of 5G networks. However, the high-bandwidth mmWave signal is susceptible to blockage by various obstacles, which results in very large and frequent degradation in the quality of the received signals. TCP, the most representative transport layer protocol, suffers from significant performance degradation due to the very dynamic channel conditions of the mmWave signal. Therefore, in this paper, we propose a congestion control algorithm that guarantees sufficient throughput in 5G mmWave networks and that does not significantly worsen TCP fairness. The proposed algorithm, which is a modification of Scalable TCP (S-TCP) that is designed for high-speed networks, provides a more stable performance than the existing TCP congestion control algorithm in mmWave networks through simple modifications. In various simulation experiments that considered the actual mobile user environment, the proposed mmWave Scalable TCP (mmS-TCP) algorithm demonstrated throughput up to 2.4 times higher than CUBIC TCP in single flow evaluation, and the inter-protocol fairness index when competing with CUBIC flow significantly improved from 0.819 of S-TCP to 0.9733. Moreover, the mmS-TCP algorithm reduced the number of duplicated ACKs by 1/4 compared with S-TCP, and it improved the average total throughput and intra-protocol fairness simultaneously.
毫米波（mmWave）频段可提供每秒多吉比特的数据速率，在实现 5G 网络的吞吐量目标方面将发挥重要作用。然而，高带宽 mmWave 信号容易被各种障碍物阻挡，从而导致接收信号的质量大幅且频繁下降。TCP 是最具代表性的传输层协议，由于 mmWave 信号的信道条件非常动态，因此其性能会显著下降。因此，在本文中，我们提出了一种拥塞控制算法，该算法可确保在 5G mmWave 网络中实现足够的吞吐量，并且不会显著降低 TCP 的公平性。该算法是为高速网络设计的可扩展 TCP（S-TCP）的一种修改，通过简单的修改，它在 mmWave 网络中提供了比现有 TCP 拥塞控制算法更稳定的性能。在考虑实际移动用户环境的各种仿真实验中，与 CUBIC TCP 相比，所提出的 mmWave 可扩展 TCP（mmS-TCP）算法在单流评估中实现了高达 2.4 倍的吞吐量，并且与 CUBIC 流竞争时的协议间公平性指数从 S-TCP 的 0.819 显著提高到 0.9733。此外，与 S-TCP 相比，mmS-TCP 算法将重复 ACK 的数量减少了 1/4，同时提高了平均总吞吐量和协议内公平性。
