An incremental redundancy hybrid automatic repeat- request (IR-HARQ)scheme based on irregular repeat-accumulate (IRA)codes is proposed. The design of rate compatible punctured IRA codes suitable for an IR-HARQ sch...An incremental redundancy hybrid automatic repeat- request (IR-HARQ)scheme based on irregular repeat-accumulate (IRA)codes is proposed. The design of rate compatible punctured IRA codes suitable for an IR-HARQ scheme is well formulated and efficiently solved by a linear-programming method, along with a one-dimensional approach for density evolution. Compared to IR-HARQ schemes based on turbo codes, simulation shows that the proposed IR-HARQ schemes based on IRA codes may achieve almost the same performance at a block size of 1 024, but better throughput at a block size of 4 096. The advantages of the proposed scheme in implementation, including decoding complexity and parallelism, make it more attractive in practice than the IR-HARQ schemes based on both turbo and LDPC codes.展开更多
With the increasing development of urban housing construction and the rapid expansion of the number of inhabitants and independent electric energy meter, a variety of tariff systems are launched, meter reading meterin...With the increasing development of urban housing construction and the rapid expansion of the number of inhabitants and independent electric energy meter, a variety of tariff systems are launched, meter reading metering becomes increasingly complex, and the traditional manual meter reading is already hard to adapt to new changes. This thesis studies the design of a centralized meter reading system. This program applies PLC technology for information transfer, which guarantees the stability of system carrier communication. This system is composed of electric energy meter, collector, concentrator and other hardware, as well as communication and management software of collection copies system. It is characterized by functions of power data collection, centralization, remote transmission, distance control, electricity analysis, line loss calculation, integrated query, and time-sharing billing. Its promotion and application will necessarily provide important technical means for power supply, property and urban utilities to improve their modernized and automatic management level.展开更多
基金The National High Technology Research and Develop-ment Program of China(863Program)(No.2006AA01Z263)the National Natural Science Foundation of China(No.60672081)+1 种基金the Natural Science Foundation of Jiangsu Province(No.BK2006502)the Open Research Fund of National Mobile Communications Research Laboratory of Southeast Uni-versity(No.2008N01)
文摘An incremental redundancy hybrid automatic repeat- request (IR-HARQ)scheme based on irregular repeat-accumulate (IRA)codes is proposed. The design of rate compatible punctured IRA codes suitable for an IR-HARQ scheme is well formulated and efficiently solved by a linear-programming method, along with a one-dimensional approach for density evolution. Compared to IR-HARQ schemes based on turbo codes, simulation shows that the proposed IR-HARQ schemes based on IRA codes may achieve almost the same performance at a block size of 1 024, but better throughput at a block size of 4 096. The advantages of the proposed scheme in implementation, including decoding complexity and parallelism, make it more attractive in practice than the IR-HARQ schemes based on both turbo and LDPC codes.
文摘With the increasing development of urban housing construction and the rapid expansion of the number of inhabitants and independent electric energy meter, a variety of tariff systems are launched, meter reading metering becomes increasingly complex, and the traditional manual meter reading is already hard to adapt to new changes. This thesis studies the design of a centralized meter reading system. This program applies PLC technology for information transfer, which guarantees the stability of system carrier communication. This system is composed of electric energy meter, collector, concentrator and other hardware, as well as communication and management software of collection copies system. It is characterized by functions of power data collection, centralization, remote transmission, distance control, electricity analysis, line loss calculation, integrated query, and time-sharing billing. Its promotion and application will necessarily provide important technical means for power supply, property and urban utilities to improve their modernized and automatic management level.