Water-environment monitoring network (WMN) is a wireless sensor network based real-time system, which collects, transmits, analyzes and processes water-environment parameters in large area. Both cluster selection mech...Water-environment monitoring network (WMN) is a wireless sensor network based real-time system, which collects, transmits, analyzes and processes water-environment parameters in large area. Both cluster selection mechanisms and energy saving strategies play an important role on designing network routing protocols for the WMN. Since those existing routing algorithms can not be used directly in the WMN, we thus propose an improved version of LEACH, a LEACH-Head Expected Frequency Appraisal (LEACH-HEFA) algorithm, for the WMN in this paper. Simulation results show that the LEACH-HEFA can balance the energy consumption of nodes, rationalize the clustering process and prolong the network lifetime significantly in the WMN. It indicates that the LEACH-HEFA is suitable to the WMN.展开更多
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 Repeti...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 with small group size and small link PLR. Our further studies show that better performance can be obtained by combining the HEC-PR scheme with other traditional HEC schemes such as Type I HARQ and Type II HARQ techniques. Based on this idea, in this paper, a novel Adaptive HEC (AHEC) scheme combining the HEC-PR scheme with Type I and Type II HARQ techniques is proposed to satisfy a certain PLR requirement for delay bounded multicast services. Furthermore, the performance of the AHEC scheme is optimized by choosing the scheme with the least needed redundancy information automatically among the three HEC schemes. Finally, by applying the AHEC scheme in a typical wireless DVB scenario, we analyze the performances of the AHEC scheme and compare it with the HEC-PR scheme and an Adaptive Forward Error Correction (AFEC) scheme. The results show that the proposed AHEC scheme outperforms both the AFEC scheme and the HEC-PR scheme.展开更多
文摘Water-environment monitoring network (WMN) is a wireless sensor network based real-time system, which collects, transmits, analyzes and processes water-environment parameters in large area. Both cluster selection mechanisms and energy saving strategies play an important role on designing network routing protocols for the WMN. Since those existing routing algorithms can not be used directly in the WMN, we thus propose an improved version of LEACH, a LEACH-Head Expected Frequency Appraisal (LEACH-HEFA) algorithm, for the WMN in this paper. Simulation results show that the LEACH-HEFA can balance the energy consumption of nodes, rationalize the clustering process and prolong the network lifetime significantly in the WMN. It indicates that the LEACH-HEFA is suitable to the WMN.
文摘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 with small group size and small link PLR. Our further studies show that better performance can be obtained by combining the HEC-PR scheme with other traditional HEC schemes such as Type I HARQ and Type II HARQ techniques. Based on this idea, in this paper, a novel Adaptive HEC (AHEC) scheme combining the HEC-PR scheme with Type I and Type II HARQ techniques is proposed to satisfy a certain PLR requirement for delay bounded multicast services. Furthermore, the performance of the AHEC scheme is optimized by choosing the scheme with the least needed redundancy information automatically among the three HEC schemes. Finally, by applying the AHEC scheme in a typical wireless DVB scenario, we analyze the performances of the AHEC scheme and compare it with the HEC-PR scheme and an Adaptive Forward Error Correction (AFEC) scheme. The results show that the proposed AHEC scheme outperforms both the AFEC scheme and the HEC-PR scheme.
