On the Throughput Performance of TCP Cubic in Millimeter-Wave Cellular Networks

In this paper, we study a cross-layer analysis framework for the performance evaluation of TCP over millimeter-Wave (mmWave) fading channels in the fifth-generation (5G) cellular networks, when the truncated incremental redundancy hybrid automatic repeat request (IR-HARQ) scheme and adaptive modulation and coding (AMC) are employed. Specifically, the throughput performance of TCP Cubic, which is one of the most widely deployed TCP variants in the Internet, is investigated. For this purpose, the mmWave fading channel, approximated by Nakagami-m distribution, is captured by a finite-state Markov chain (FSMC) to develop a transmission loss model. A loss-based TCP model, which is analyzed based on the transmission loss model, is then used to analytically derive the TCP throughput performance. The numerical results quantitatively show the effect of different parameters/settings of AMC, IR-HARQ, blockages and mmWave fading channels on the TCP performance and support the optimal selection of parameters to maximize the system throughput. Monte Carlo simulations are also performed to validate the analytical results.