Backlog and Delay Reasoning in HARQ System

Abstract

Recently, hybrid-automatic-repeat-request (HARQ) systems have been favored in particular state-of-the-art communications systems since they provide the practicality of error detections and corrections aligned with repeat-requests when needed at receivers. The queueing characteristics of these systems have taken considerable focus since the current technology demands data transmissions with a minimum delay provisioning. In this paper, we investigate the effects of physical layer characteristics on data link layer performance in a general class of HARQ systems. Constructing a state transition model that combines queue activity at a transmitter and decoding efficiency at a receiver, we identify the probability of clearing the queue at the transmitter and the packet-loss probability at the receiver. We determine the effective capacity that yields the maximum feasible data arrival rate at the queue under quality-ofservice constraints. In addition, we put forward non-asymptotic backlog and delay bounds. Finally, regarding three different HARQ protocols, namely Type-I HARQ, HARQ-chase combining (HARQ-CC) and HARQ-incremental redundancy (HARQ-IR), we show the superiority of HARQ-IR in delay robustness over the others. However, we further observe that the performance gap between HARQ-CC and HARQ-IR is quite negligible in certain cases. The novelty of our paper is a general cross-layer analysis of these systems, considering encoding/decoding in the physical layer and delay aspects in the data-link layer.

Effective Capacity in Wireless Networks: A Comprehensive Survey

“…Traditional ARQ [117] Selective Repeat ARQ (SR-ARQ) [160] Network Coded ARQ (NC-ARQ) [226] Two-Mode ARQ [226] Multi-Layer ARQ [226] Traditional HARQ [49] Type-1 HARQ [173] Chase combining HARQ (CC-HARQ) [173] Incremental redundancy HARQ (HARQ-IR) [173], [200], [296] Persistent HARQ [226] Truncated HARQ [226]…”

QoE-Aware Sustainable Throughput for Energy-Efficient Video Streaming

“…Reference [8] considered the sustainable throughput to be the maximal throughput in a WLAN scenario to assure stability. Reference [9] reported the so-called reliable throughput values for mobile channels with focus on automatic repeat-request (ARQ). The latter works have in common that throughput values are obtained from traffic modeling through analytic models, similar to our work.…”

“…The challenge consists in modeling the interdependencies between throughput R and freeze probability p freeze such that the sustainable throughput at a tolerable QoE deviation δ QoE according to (9) can be obtained. The maximal throughput that does not allow the freeze probability to exceed a given bound p freeze,max has to be determined.…”

“…The channel can be perceived as being off due to reasons like coverage issues, scheduling actions, and repair efforts of symbol errors by the underlying ARQ mechanism [9], to ensure the highest-possible degree of completeness and order of packets in the corresponding stream. The buffer used for interconnecting the CBR inlet with the VBR outlet is necessary for scheduling and repair.…”

“…2) The VBR model of the channel can be refined, considering the ARQ behavior at hand [9]. 3) The CBR characteristic at the inlet can be exchanged to a VBR characteristic with two or more states, potentially modulating each other in a multiplicative fashion [33].…”