摘要:
After checking a status of frequency band usage of a primary system by preliminary sensing, a master node transmits to slave nodes a sensing request containing a target frequency band for cooperative sensing. The slave nodes perform spectrum sensing according to specified parameters and send, as responses, results thereof to the master node. The master node collectively receives these results, comprehensively determines the sensing results of the slave nodes, and makes a final determination on whether or not the target frequency band is available.
摘要:
In cooperative sensing in which a plurality of cognitive radio apparatus collaboratively exchange sensing information on a status of frequency band usage as a secondary system, the sensing information is efficiently exchanged in the secondary system without influencing communication of the primary system. In a radio communication system according to this invention, a first radio communication device includes means for observing a surrounding radio communication environment, means for converting information obtained by the observation into a parameter used for radio communication, and means for performing transmission by using the parameter, and a second radio communication device includes means for receiving a signal transmitted from the first radio communication device and means for extracting, from the received signal, information on the surrounding radio communication environment that is observed on a transmission side.
摘要:
Provided is a radio communication system including a plurality of cognitive radio apparatuses each including at least: a transmission/reception element; and a detection element for detecting a radio wave transmitted from a radio apparatus of another radio communication system, in which the radio communication system further includes a control section for determining a frequency band on which each cognitive radio apparatus of a radio apparatus group including the plurality of cognitive radio apparatuses is to detect the radio wave.
摘要:
Provided is a radio communication system including a plurality of cognitive radio apparatuses each including at least: a transmission/reception element; and a detection element for detecting a radio wave transmitted from a radio apparatus of another radio communication system, in which the radio communication system further includes a control section for determining a frequency band on which each cognitive radio apparatus of a radio apparatus group including the plurality of cognitive radio apparatuses is to detect the radio wave.
摘要:
In cooperative sensing in which a plurality of cognitive radio apparatus collaboratively exchange sensing information on a status of frequency band usage as a secondary system, the sensing information is efficiently exchanged in the secondary system without influencing communication of the primary system. In a radio communication system according to this invention, a first radio communication device includes means for observing a surrounding radio communication environment, means for converting information obtained by the observation into a parameter used for radio communication, and means for performing transmission by using the parameter, and a second radio communication device includes means for receiving a signal transmitted from the first radio communication device and means for extracting, from the received signal, information on the surrounding radio communication environment that is observed on a transmission side.
摘要:
A communication device, a communication method and a communication system that enable an increase in channel capacity at cell edges of a plurality of cells. Data transmission is implemented by transmission stations, which are base stations of adjacent cells, by MIMO transmission. A relay station receives radio waves that are transmitted by both the transmission station and the transmission station, and acquires data transmitted by the transmission station and data transmitted by the transmission station. The relay station transmits data to reception stations in adjacent cells according to multi-user MIMO transmission. The data transmitted by the transmission station is received by the reception station via the relay station, and the data transmitted by the transmission station is received by the reception station via the relay station. The present invention can be used in cellular systems.
摘要:
According to the present invention, a MOSFET for an input/output protective circuit in which a source diffusion layer, a drain diffusion layer and a gate electrode are formed on a semiconductor substrate comprises a high melting point metal silicide layer disposed on the drain diffusion layer through a first insulating film, a metal wire layer disposed on the high melting point metal silicide layer through a second insulating film, at least two first contact holes for electrically connecting the high melting point metal silicide layer and the metal wire layer, and a second contact hole for electrically connecting the high melting point metal silicide layer and the drain diffusion layer, wherein the second contact hole is disposed at a substantial center between the two first contact holes.
摘要:
A dynamic memory circuit which can operate at a high speed and with a reduced amount of current noise is disclosed. The memory circuit includes dynamic type memory cells which necessitate restoring operation for rewritting read out data thereto, a read circuit for performing a read out operation in response to an active level of an externally supplied control signal and a restore circuit for performing the restoring operation in response to change of the externally supplied control signal to its inactive level.
摘要:
A communication device, a communication method and a communication system that enable an increase in channel capacity at cell edges of a plurality of cells. Data transmission is implemented by transmission stations, which are base stations of adjacent cells, by MIMO transmission. A relay station receives radio waves that are transmitted by both the transmission station and the transmission station, and acquires data transmitted by the transmission station and data transmitted by the transmission station. The relay station transmits data to reception stations in adjacent cells according to multi-user MIMO transmission. The data transmitted by the transmission station is received by the reception station via the relay station, and the data transmitted by the transmission station is received by the reception station via the relay station. The present invention can be used in cellular systems.
摘要:
An ink jet recording apparatus is provided with a black head and a plurality of color heads. The black head has a predetermined number of first orifices aligned at predetermined intervals (e.g. 0.0169 mm) in a sub scanning direction (direction in which a print medium travels). The plurality of color heads eject different colored ink drops. Each color head has the predetermined number of second orifices aligned in the sub scanning direction perpendicular to the main scanning direction. The second orifices of adjacent color heads are aligned in a main scanning direction perpendicular to the sub scanning direction.