Vehicle-to-vehicle (V2V) communication is a technology that can wirelessly exchange information on the speed and position of nearby vehicles, helping to avoid collisions, alleviate traffic congestion, improve environment. The 3rd Generation Partnership Project (3GPP) has specified methods reliability V2V sidelink (SL) by implementing hybrid automatic repeat request (HARQ) in casting strategy co...

In this paper, the parameters of the LTE system in DL are investigated. These parameters include the effect of the Hybrid Adaptive Repeat and Request henceforth (HARQ) on the Signal to Noise Ratio (SNR), Block Error Rate (BLER), and throughput. The paper deals with three cases of Channel Quality Indicator (CQI): 3,7 and 15.The results showed that the HARQ procedure can improve the BLER and the ...

Incremental Redundancy Hybrid Automatic Repeat Request (HARQ-IR) retransmission protocol was developed to reduce the transmission errors over fading channels through multiple retransmissions. In this paper, we implement HARQ-IR for Single User MIMO systems with Successive Interference Canceling (SIC) receiver. We perform the throughput and reliability analysis for the MIMO system with Closed Lo...

Real-time applications usually not only have a certain Packet Loss Ratio (PLR) requirement but also can have strict delay constraints. In the past, we proposed a Hybrid Error Correction (HEC) scheme with Packet Repetition (PR) technique for guaranteeing a certain PLR requirement under strict delay constraints. Unfortunately, the HEC-PR scheme can only work efficiently in multicast scenarios wit...

Next generation cellular networks will present challenging interference scenarios due to the difficulty of centralized planning and continued support of mobility. In this context, modeling and analytical study is still required for time-varying inter-cell interference and imperfect resolution of the channel state at the transmission end. In this paper, we first present a mathematical framework ...

In data packet communication systems over multipath frequency-selective channels, hybrid automatic repeat request (HARQ) protocols are usually used in order to ensure data reliability. For single-carrier packet transmission in slow fading environment, an identical retransmission of the same packet, due to a decoding failure, does not fully exploit the available time diversity in retransmission-...

In this paper, we propose novel Hybrid Automatic Repeat re-Quest (HARQ) strategies used in conjunction with hybrid relaying schemes, named as H-ARQ-Relaying. The strategies allow the relay to dynamically switch between amplify-andforward/compress-and-forward and decode-and-forward schemes according to its decoding status. The performance analysis is conducted from both the spectrum and energy e...

In this paper, the combination of packet level Space-Time Block Coding (STBC) with an adaptive Hybrid Automatic Repeat reQuest (HARQ) algorithm for efficient and reliable multicast transmission in UMTS networks is proposed. The aim of this paper is to provide a cross-layer design of packet-data transmissions in Multiple-Input Multiple-Output (MIMO) systems employing orthogonal STBC over Rayleig...

あらまし 最近,限られた帯域幅での高速伝送技術として MIMO 多重が注目されている.このうちの 1 つとして固有モード MIMO 多重(E-SDM: Eigenbeam-Space Division Multiplexing)が知られている.E-SDM では MIMO チャネル情報を送受信 間で共有し,複数の直交したチャネルを形成して異なる信号を同時に送信する.直交チャネル状態に応じて電力配分と適 応変調を行うことで高い伝送効率を実現できる.ところで,今後の移動無線通信ではパケット伝送が主流になると予想され, 誤り訂正符号化と自動再送要求(ARQ)を組み合わせたハイブリット ARQ(HARQ)が重要な技術となる.そこで本論文では, ターボ符号化 HARQ を用いた E-SDM のスループット特性を計算機シミュレーションにより明らかにしている. キーワード MIMO 多重,E-SDM...

LTE networks have been rapidly commercialized for 4G cellular communications systems in all over the world as well as Korea. Because many internet applications use TCP as their transport layer protocol, TCP throughput measurements and its performance improvements in LTE networks is very important. In this paper, we analyze the impact of “in-sequence delivery” in LTE link layer on TCP RTT increm...