In this paper, we study the efficiency-reliability tradeoff issue of hybrid ARQ (HARQ) scheme in noisy long delay network such as satellite-terrestrial hybrid network, where both long wireless round trip time and time-varying error characteristics have to be considered. A new adaptive HARQ scheme is proposed to acquire efficiency-reliability joint optimization. By adjusting coding rate accordin...

The bit error rate (BER) performance of DS-CDMA in a frequency-selective fading channel can be significantly improved by the use of frequency-domain equalization (FDE). However, the presence of a residual inter-chip interference (ICI) after FDE distorts the orthogonality among the spreading codes and the BER performance of the multicode DS-CDMA degrades as the number of multiplex order increase...

Hybrid automatic repeat request (HARQ) is an essential technology that efficiently reduces the transmission error rate. However, for ultra-reliable low latency communications (URLLC) in 5th generation mobile communication systems and beyond, increase due to retransmission must be minimized HARQ. In this paper, we propose a highly-efficient low-latency HARQ method built on non-orthogonal multipl...

The age of information (AoI) has attracted increasing attentions as a new metric and tool to capture the timeliness reception freshness data, which is different from conventional such outage, delay, throughput. While most existing works focused on AoI analysis optimizing method, update system design by utilizing diversity reduce not fully exploited so far. Inspired this fact, novel status desig...

The 5th generation (5G) mobile communication system requires high throughput for high quality user experience. In this paper, a novel Hybrid Automatic Repeat Request (HARQ) scheme based on packet coding is proposed. The idea is that a parity block is transmitted when code block error rate (CBER) of all turbo code blocks of transmission packet is less than or equal to the threshold of P0 and gre...

—Efficiently using scarce energy is more critical for the nodes which are supplied by energy harvesting. However, it is difficult to optimize the transmit energy of each retransmission when future Channel State Information (CSI) and accurate retransmission number cannot be obtained in Hybrid Automatic Repeat Request (HARQ) system. In this paper, we propose a novel HARQ scheme to allocate the b...

This paper studies the potential improvements in terms of energy efficiency and system throughput of a hybrid automatic retransmission request (HARQ) mechanism. The analysis includes both the physical (PHY) and medium access (MAC) layers. We investigate the trade-off provided by HARQ, which demands reduced transmit power for a given target outage probability at the cost of more accesses to the ...

We analyze the opportunistic relaying based on hybrid automatic repeat request (HARQ) transmission over the block-fading channel with absence of channel state information (CSI) at the transmitter nodes. We assume that both the source and the relay are allowed to vary their transmission rate between the HARQ transmission rounds. We solve the problem of throughput maximization with respect to the...

Abstract In the next generation wireless communication systems, high-speed packet services will be in great demand, and hence error control technique is indispensable. Hybrid automatic repeat request (HARQ) is a well-known important error controlling technique. Joint FDE and inter-chip interference (ICI) cancellation based on the minimum mean square error (MMSE) criterion can achieve frequency ...

Abstract In direct sequence code division multiple access (DS-CDMA), frequency-domain equalization (FDE) based on minimum mean square error (MMSE) criterion and inter-chip interference (ICI) cancellation can be applied to exploit the channel frequency-selectivity and therefore, can replace the conventional rake combining while offering a much improved bit error rate (BER) performance. In the ne...