In this letter,we first put forward a new basic problem to the famous vector perturbation(VP) precoding that whether the extended constellation of VP could transmit more information bits.Then,we propose an opportunist...In this letter,we first put forward a new basic problem to the famous vector perturbation(VP) precoding that whether the extended constellation of VP could transmit more information bits.Then,we propose an opportunistic vector perturbation(OVP) precoding with superposition signalling scheme,which is aimed at getting the performance of VP closer to capacity limit.The main idea is using subsequent recoverable data symbol vector to perturb currently transmitting data symbol vector opportunistically.Analysis and simulation results show that the proposed OVP can transmit more valid information bits than conventional VP at the same transmit power,modulation order and number of antennas.展开更多
An object segment similarity function is taken into account from the continuous media frames to measure the individual streaming profit of certain segment versions of a media object.Therefore,a new segment version-bas...An object segment similarity function is taken into account from the continuous media frames to measure the individual streaming profit of certain segment versions of a media object.Therefore,a new segment version-based transcoding(SVT)mechanism is derived for a quality of service(QoS)of client-centric media streaming in wireless mobile networks.The derived function utilizes the fuzzy similarity of certain segment versions of an object.This mechanism provides the effectiveness of reduction of the stream startup latency among segment versions,and the average access of each version.Thus,the proposed segment version transcoding mechanism reduces packet loss which in turn increases streaming performance and throughput.The performance of the partitioned segment versions is simulated and some segment versions are completed.The simulation results show that the proposed mechanism outperforms the other mechanisms in average cache hit ratio and in average startup latency ratio.展开更多
基金supported in part by Key Project of National Natural Science Foundation of China(61231008)National Natural Science Foundation of China (61301168,61271176)+1 种基金Natural Science Basic Research Plan in Shaanxi Province of China (2013JQ8001)Fundamental Research Funds for the Central Universities and the 111 Project(B08038)
文摘In this letter,we first put forward a new basic problem to the famous vector perturbation(VP) precoding that whether the extended constellation of VP could transmit more information bits.Then,we propose an opportunistic vector perturbation(OVP) precoding with superposition signalling scheme,which is aimed at getting the performance of VP closer to capacity limit.The main idea is using subsequent recoverable data symbol vector to perturb currently transmitting data symbol vector opportunistically.Analysis and simulation results show that the proposed OVP can transmit more valid information bits than conventional VP at the same transmit power,modulation order and number of antennas.
基金Project(2011)financially supported by Research Funds of Chonbuk National University,Korea
文摘An object segment similarity function is taken into account from the continuous media frames to measure the individual streaming profit of certain segment versions of a media object.Therefore,a new segment version-based transcoding(SVT)mechanism is derived for a quality of service(QoS)of client-centric media streaming in wireless mobile networks.The derived function utilizes the fuzzy similarity of certain segment versions of an object.This mechanism provides the effectiveness of reduction of the stream startup latency among segment versions,and the average access of each version.Thus,the proposed segment version transcoding mechanism reduces packet loss which in turn increases streaming performance and throughput.The performance of the partitioned segment versions is simulated and some segment versions are completed.The simulation results show that the proposed mechanism outperforms the other mechanisms in average cache hit ratio and in average startup latency ratio.
