Mobility management is an important aspect of the LEO systems. In terrestrial wireless network, the movement of the user triggers the location updating and determines the paging scheme, while in LEO satellite systems,...Mobility management is an important aspect of the LEO systems. In terrestrial wireless network, the movement of the user triggers the location updating and determines the paging scheme, while in LEO satellite systems, the location updating and paging is mainly based on the movement of satellite. Terrestrial location management techniques must be altered to fit LEO systems. This paper introduces a modified movement based location update and paging scheme in LEO networks. In this scheme we propose the meta cell concept, which includes two spot beams of one satellite. First we present the location management scheme based on the architecture with meta cell location area. Then an analytical model is applied to formulate the cost of location updating and location paging for the and movement meta cell based dynamic location update scheme. The comparison of performance between meta cell architecture method and conventional signal spot cell architecture method is provided to demonstrate the cost effectiveness and robust of the proposed scheme under various parameters. To reduce the impact of meta cell architecture on location paging cost, we present forced location update strategy which used in the cases that the meta cell includes the two spot beams from different satellites.展开更多
The communication in the physical layer between an interrogator and a tag of a passive Radio Frequency Identification (RFID) system operating between 860-960 MHz is defined by the Gen 2 protocol. The tag can be cons...The communication in the physical layer between an interrogator and a tag of a passive Radio Frequency Identification (RFID) system operating between 860-960 MHz is defined by the Gen 2 protocol. The tag can be considered a remote executing unit or a computer that executes instructions from the Gen 2 protocol. The selection of the parameter and command configuration within the protocol limitations is critical especially if the time available for the memory operations in a passive RFID system is limited. An effort is made to map the operation of the tag not in its states of operation as elaborately explained in the protocol but rather in its elementary format. The research reported in this article identifies all the parameters that affect the dynamic operation of the tag. The operation is further divided into singulation, read and write; identifying the significant parameters in each case. The choices of the different commands that can be adopted to perform identical operations on the tag are analyzed. The elements to consider in selecting the optimum command configuration are described. The impact of the different parameter and command configuration on the singulation, read and write time is calculated and recorded using a tested Gen 2 simulator program.展开更多
文摘Mobility management is an important aspect of the LEO systems. In terrestrial wireless network, the movement of the user triggers the location updating and determines the paging scheme, while in LEO satellite systems, the location updating and paging is mainly based on the movement of satellite. Terrestrial location management techniques must be altered to fit LEO systems. This paper introduces a modified movement based location update and paging scheme in LEO networks. In this scheme we propose the meta cell concept, which includes two spot beams of one satellite. First we present the location management scheme based on the architecture with meta cell location area. Then an analytical model is applied to formulate the cost of location updating and location paging for the and movement meta cell based dynamic location update scheme. The comparison of performance between meta cell architecture method and conventional signal spot cell architecture method is provided to demonstrate the cost effectiveness and robust of the proposed scheme under various parameters. To reduce the impact of meta cell architecture on location paging cost, we present forced location update strategy which used in the cases that the meta cell includes the two spot beams from different satellites.
文摘The communication in the physical layer between an interrogator and a tag of a passive Radio Frequency Identification (RFID) system operating between 860-960 MHz is defined by the Gen 2 protocol. The tag can be considered a remote executing unit or a computer that executes instructions from the Gen 2 protocol. The selection of the parameter and command configuration within the protocol limitations is critical especially if the time available for the memory operations in a passive RFID system is limited. An effort is made to map the operation of the tag not in its states of operation as elaborately explained in the protocol but rather in its elementary format. The research reported in this article identifies all the parameters that affect the dynamic operation of the tag. The operation is further divided into singulation, read and write; identifying the significant parameters in each case. The choices of the different commands that can be adopted to perform identical operations on the tag are analyzed. The elements to consider in selecting the optimum command configuration are described. The impact of the different parameter and command configuration on the singulation, read and write time is calculated and recorded using a tested Gen 2 simulator program.