摘要:
A plurality of wireless communication methods are combined, networks to be used are dynamically selected by evaluating each network quality, and a packet format is changed adaptively to realize necessary reliability. The wireless communication apparatus has a network interface, a data interface, a quality interface, an allocation control part, a quality database, a quality update part, communication units and antennas. The wireless communication apparatus receives data and a requested quality from an application apparatus, selects the communication unit and communication method suitable for the requested quality, and transmits the data and requested quality. The communication unit receives a communication quality of the communication partner, and the quality update part updates the communication quality state in the quality database.
摘要:
In the construction of a wireless network in a building, structure conditions such as the floor plan of the building and the shape of the floor, material conditions such as materials for structures, and the like have a great effect on radio wave propagation characteristics. This causes a problem that unless these pieces of information are taken into consideration, an accurate layout design of wireless base stations cannot be made. In the construction of a new wireless network in a building, a wireless network similar to structure conditions of a newly constructed building is extracted from structure conditions of past buildings in which a wireless network is constructed. The layout positions of wireless base stations used in the extracted wireless network are regarded as the layout positions of wireless base stations in the new wireless network.
摘要:
In the construction of a wireless network in a building, structure conditions such as the floor plan of the building and the shape of the floor, material conditions such as materials for structures, and the like have a great effect on radio wave propagation characteristics. This causes a problem that unless these pieces of information are taken into consideration, an accurate layout design of wireless base stations cannot be made. In the construction of a new wireless network in a building, a wireless network similar to structure conditions of a newly constructed building is extracted from structure conditions of past buildings in which a wireless network is constructed. The layout positions of wireless base stations used in the extracted wireless network are regarded as the layout positions of wireless base stations in the new wireless network.
摘要:
A multistage relay communication system 100 includes a trunk network 1 and branch networks 2 (2a, 2b), each of which includes one or more communication apparatuses 4. The communication apparatus 4 can switch between a trunk mode to operate in the trunk network 1 and a branch mode to operate in the branch network 2. In the trunk network 1, the communication apparatus 4 carries out fixing of a communication path and redundancy of data based on a path table in order to achieve real-timeness and a data arrival rate. Meanwhile, in the branch network 2, when a communication failure occurs, the communication apparatus 4 autonomously searches for a communication path and constructs a path table, in order to at least secure a data arrival rate even if real-timeness is impaired within an allowable range.
摘要:
A method for measuring a radio wave propagation environment includes installing radio signal transmission and reception apparatuses where a radio network system is to be constructed and obtaining an electromagnetic wave measured value of a signal between transmission and reception apparatuses; estimating an electromagnetic wave propagation state of the signal using an electrical property and information on a three-dimensional structure at the site to obtain an electromagnetic wave estimated value; making a comparison between measured and estimated values for each time of day to determine when errors between measured and estimated values exceed a reference value; obtaining an electromagnetic path between transmission and reception apparatuses; and modifying structure information in the wave path to re-obtain the estimated value; and comparing the measured re-obtained estimated value to modify the three-dimensional structure information so that the error value becomes smaller.
摘要:
A method for measuring a radio wave propagation environment includes installing radio signal transmission and reception apparatuses where a radio network system is to be constructed and obtaining an electromagnetic wave measured value of a signal between transmission and reception apparatuses; estimating an electromagnetic wave propagation state of the signal using an electrical property and information on a three-dimensional structure at the site to obtain an electromagnetic wave estimated value; making a comparison between measured and estimated values for each time of day to determine when errors between measured and estimated values exceed a reference value; obtaining an electromagnetic path between transmission and reception apparatuses; and modifying structure information in the wave path to re-obtain the estimated value; and comparing the measured re-obtained estimated value to modify the three-dimensional structure information so that the error value becomes smaller.
摘要:
A communication device reduces a processing time required at the time of mutually converting different wireless or wired communication protocol and improves a real-time property. The communication device includes two or more communication units which communicate with two or more external devices and a communication controller which processes communication data. The communication controller has table information that associates a communication path, a type of the communication unit, and conversion-info, and an input and output unit that inputs and outputs the table information. According to the added conversion-info, a conversion unit sequentially performs various conversion processes (protocol conversion, routing, communication quality evaluation, fragmentation/integration of communication interface, fragment/defragment process, frame multiplication/integration, and frequency setting).
摘要:
A multistage relay communication system 100 includes a trunk network 1 and branch networks 2 (2a, 2b), each of which includes one or more communication apparatuses 4. The communication apparatus 4 can switch between a trunk mode to operate in the trunk network 1 and a branch mode to operate in the branch network 2. In the trunk network 1, the communication apparatus 4 carries out fixing of a communication path and redundancy of data based on a path table in order to achieve real-timeness and a data arrival rate. Meanwhile, in the branch network 2, when a communication failure occurs, the communication apparatus 4 autonomously searches for a communication path and constructs a path table, in order to at least secure a data arrival rate even if real-timeness is impaired within an allowable range.
摘要:
A communication device reduces a processing time required at the time of mutually converting different wireless or wired communication protocol and improves a real-time property. The communication device includes two or more communication units which communicate with two or more external devices and a communication controller which processes communication data. The communication controller has table information that associates a communication path, a type of the communication unit, and conversion-info, and an input and output unit that inputs and outputs the table information. According to the added conversion-info, a conversion unit sequentially performs various conversion processes (protocol conversion, routing, communication quality evaluation, fragmentation/integration of communication interface, fragment/defragment process, frame multiplication/integration, and frequency setting).
摘要:
A wireless communication system includes a wireless communication apparatus (fixed terminal) resided in a fixed station side providing a wireless antenna, a wireless communication unit, a server processing unit, a task list, a data communication unit, a buffer management unit and a buffer, and a wireless data transport apparatus (mobile terminal) resided in a mobile station side providing the wireless antenna, the wireless communication unit, a server determination unit, a task list I/O unit, the task list, a client processing unit and the buffer, thereby, the mobile terminal receives the task list from the fixed terminal to communicate data with another fixed terminal and transports not only the data but also a data acknowledgement, and the fixed terminal creates the acknowledgement to use the acknowledgement to thereby control a creation and deletion of bulk data appropriately.