Patent application number | Description | Published |
20080298341 | RADIO COMMUNICATION SYSTEM AND RADIO COMMUNICATION METHOD - A radio communication system having an interference reduction function and enabling random access is constructed without complicating a terminal structure. A base station has an interference signal detection function, performs interference signal detection intermittently and transmits a beacon signal when no interference signal is detected. A terminal starts up from a sleep mode before transmitting data, performs reception waiting, transmits data only immediately after reception of the beacon signal, transits to the sleep mode again if the beacon signal is not received and repeats the abovementioned sequence after a predetermined time elapses. | 12-04-2008 |
20090034650 | SEMICONDUCTOR INTEGRATED CIRCUIT AND METHOD FOR OPERATING ULTRA WIDE BAND-IMPULSE RADIO-TRANSMITTER - Provided is a semiconductor integrated circuit, in which a transmit pulse having an impulse waveform is produced using pull-up and pull-down currents of the charge pumps of pattern-generating cells of the pattern generator. During the first calibrating operation of semiconductor integrated circuit, the variation in amplitude of the transmit pulse is detected. At least one of pull-up and pull-down currents of the charge pumps is controlled according to a first calibration control signal responsive to the result of detection of the amplitude. During the second calibrating operation, the fluctuation in DC level just after producing of a repeat pulse of the transmit pulse is also detected. Imbalance between the pull-up and pull-down currents of the charge pumps are lowered according to a second calibration control signal responsive to the result of detection of the DC level fluctuation. | 02-05-2009 |
20100010690 | Radio Communication System for Controlling a Vehicle - A radio control system for controlling a vehicle includes a transmission node for transmitting vehicle control data, the vehicle control data including at least one of a measured value of a vehicle state or a driver's manipulated variable and a control target value of a control actuator in the vehicle, a reception node for receiving the vehicle control data, and a plurality of radio communication routes between the transmission node and the reception node. A radio communication route that satisfies communication limit time of transmission data including the vehicle control data and satisfies lowest required reliability of the transmission data is selected from among the radio communication routes. | 01-14-2010 |
20100103878 | WIRELESS SENSOR-NETWORK SYSTEM, SENSING TERMINAL NODE, AND BASE STATION - To correct a sensor data acquisition time with a simple hardware configuration, provided is a wireless sensor-network system including: a base station; and a plurality of sensing terminal nodes, the base station transmitting a beacon at predetermined intervals to the plurality of sensing terminal nodes, the plurality of sensing terminal nodes measuring data and transmitting, based on a reception of the beacon transmitted from the base station, the sensor data thus obtained to the base station, in which the plurality of sensing terminal nodes obtain, based on an internal clock, a time at which the beacon is received and transmit the time to the base station, and the base station corrects, based on the reception time transmitted from each of the plurality of sensing terminal nodes, the sensor data acquisition time. | 04-29-2010 |
20100103986 | Receiver - With the objective of enhancing receiving performance of a receiver with respect to pulse signals spread by spread codes, the receiver comprises an RF front-end section which performs amplification, an AD converter section which AD-converts signals outputted from the RF front-end section, a baseband section which inversely spreads the output of the AD converter section and performs signal detection and demodulation thereon, a reception environment measuring section which measures reception environment using the input signals of the baseband section, and a parameter setting section which sets parameters for respective parts on the basis of signals outputted from the reception environment measuring section. The parameter setting section sets the parameters for the respective parts to the optimum according to the environmental condition measured by the reception environment measuring section. | 04-29-2010 |
20100111146 | COMMUNICATION DEVICE AND COMMUNICATION SYSTEM - A communication device with digital and analog circuits mixedly mounted thereon, for which the influence of noise generated in its interface part on the analog circuit part can be reduced, which does not interfere with the downsizing of the communication device. The communication device has a communication part, such as semiconductor communication device, and a control part, such as a semiconductor control device operable to control the communication part. The communication part and control part are operated in asynchronization with each other. The communication part includes an analog circuit. The interface circuit of the communication part, which is interfaced with the control part, receives a clock signal supplied from the communication part and conducts a synchronous interface. The control part stops supplying the clock signal during the time when the communication part operates the analog circuit. | 05-06-2010 |
20100112959 | ELECTRONIC CIRCUIT AND RADIO COMMUNICATIONS SYSTEM - The electronic circuit includes: a micro controller unit; a timer operable to measure a standby time of the micro controller unit; a buffer circuit connected with an output-signal terminal of the timer; a logic circuit controlled by an output signal of the timer and an output signal of the micro controller unit; and a power-on switch controlled by the logic circuit. The buffer circuit has no protection diode connected with an input terminal thereof on a power-source side, and connected to a common power source shared with the micro controller unit. The switch is one for controlling the power source of the micro controller unit and buffer circuit. The micro controller unit is made to transition to an active state to either a standby state or a power-source cutoff state during the standby time. | 05-06-2010 |
20110070909 | Method of communication and base station - There are provided a method of communication which can reliably transmit information from a base station to a wireless terminal in a system which can reduce power consumption by intermittent operation in which the wireless terminal repeats operating state and suspended state by power on and off and the base station used for the method. The method includes the steps of storing base station information such as a command or data supplied to the wireless terminal in the base station, transferring the wireless terminal from the suspended state to the operating state to transmit information from the sensor to the base station, coupling the base station information stored in the base station to a response signal to transmit it to the wireless terminal in the operating state for transmitting the sensor information, and returning the wireless terminal to the suspended state after completing the transmission of the base station information and sensor information. | 03-24-2011 |
20110092223 | Reciever, frequency deviation measuring unit and positioning and ranging system - In a system for measuring a time difference of arrival of signals for positioning, an accurate time difference is measured by a receiver which is reduced in power consumption, size, and cost. The system comprises a node (under measurement) for transmitting a positioning signal, a reference station for transmitting a reference signal, and a plurality of access points for receiving the positioning signal and reference signal, and a server connected to the plurality of access points through a network. Each of the plurality of access points measures a time difference between the reception of the positioning signal and the reception of the reference signal, and a frequency deviation from the reference station, using a clock signal and a signal for shifting the clock signal, and the server calculates the position of the node based on the measured time difference and frequency deviation. | 04-21-2011 |
20110182196 | NETWORK SYSTEMS, NETWORK INTERCONNECTION DEVICES, AND DATA TRANSMISSION SCHEME - A network system includes one or more terminals which transmit acquired data to a first network, a network interconnection device which is connected to the terminal via the first network and which receives the data from the terminal, and a management server which is connected to the network interconnection device via a second network and which receives the data from the network interconnection device; the terminal transmits the same data to the network interconnection device via the first network by a frequency corresponding to redundancy; the data contains the priority according to the contents of the data; and the network interconnection device acquires the communication quality of the second network and instructs the terminal to transmit the data according to redundancy determined based upon the acquired communication quality and the priority. | 07-28-2011 |
20110310748 | COORDINATOR, WIRELESS NODE AND WIRELESS COMMUNICATION SYSTEM - A wireless communication system provides high reliability wireless communications even when large scale interference affecting the entire system has occurred in ad hoc wireless communication systems. The node, access point, and intermediate nodes are each equipped with multiple wireless standards, and notify a wireless communication control device called a coordinator that sets the network communication paths with communication path information obtained by measuring the state of communication paths in the vicinity of their own respective nodes. The coordinator that now knows the communication status, issues instructions for setting plural routes using multiple wireless standards between the node and the access points as well as which wireless standard to use to implement communications between each intermediate zone, and each intermediate node conveys the measurement data while complying with those instructions. | 12-22-2011 |
20120155301 | Wireless Network System and Wireless Communication Device - A wireless communication device includes a sensor processing unit that generates sensor data including a measurement result acquired by a sensor; a communication measurement unit that generates communication quality data including a communication state for transmitting a packet; a compression determination unit that determines compression rates of first sensor data and first communication quality data according to the contents of the first sensor data including the transmitted sensor data and the generated sensor data or the contents of the first communication quality data including the transmitted sensor data and the generated communication quality data; a compression unit that compresses the first sensor data and the first communication quality data according to the determined compression rates; and a wireless communication unit that transmits a packet including the compressed first sensor data and the compressed first communication quality data to another wireless communication device or the access point. | 06-21-2012 |
20130040590 | ELECTRONIC CIRCUIT AND RADIO COMMUNICATIONS SYSTEM - The electronic circuit includes: a micro controller unit; a timer operable to measure a standby time of the micro controller unit; a buffer circuit connected with an output-signal terminal of the timer; a logic circuit controlled by an output signal of the timer and an output signal of the micro controller unit; and a power-on switch controlled by the logic circuit. The buffer circuit has no protection diode connected with an input terminal thereof on a power-source side, and connected to a common power source shared with the micro controller unit. The switch is one for controlling the power source of the micro controller unit and buffer circuit. The micro controller unit is made to transition to an active state to either a standby state or a power-source cutoff state during the standby time. | 02-14-2013 |
20130121238 | RELAY COMMUNICATION APPARATUS AND MULTISTAGE RELAY COMMUNICATION SYSTEM - A multistage relay communication system | 05-16-2013 |
20130214974 | ANTENNA BEAM SCAN MODULE, AND COMMUNICATION APPARATUS USING THE SAME - Signals are maintained to be in phase at beam input ports of a Rotman lens antenna, and thus scanning at non-step antenna beam angles can be realized without increasing the number of input beams. The present invention provides an antenna beam scan module including: a Rotman lens that has plural beam ports and plural antenna ports; plural antenna elements; relative phase detectors that detect a relative phase difference between the signals input to the adjacent beam ports; phase shifters that offset the relative phase difference between the signals supplied to the adjacent beam ports on the basis of the relative phase difference detected by the relative phase detectors; and switches that select routes of the signals supplied to the beam ports through variable amplifiers, wherein the phase shifters are arranged on alternate routes through which the signals are supplied to the plural beam ports. | 08-22-2013 |
20130235905 | GATEWAY WIRELESS COMMUNICATION INSTRUMENT, WIRELESS COMMUNICATION SYSTEM, AND COMMUNICATION CONTROL METHOD - A period is defined to execute the sequences (processes) of communication data acquisition, measuring communication quality, communication quality data acquisition, and channel change. Processing is controlled to execute each process within a time limit set for each process and execute all processes in one cycle. This avoids that a delayed sequence influences and delays other sequences and can suppress delays. If processing fails to finish a sequence, it will resume the same sequence in the next cycle. For communication stations sharing timeslots, there are provided offset periods differing in length before the start of carrier sense in the timeslots for these stations. Consequently, even under a condition in which packet collision may occur, the collision of packets can be avoided by detecting a packet sent to another station by carrier sense. Moreover, by controlling sending priority of packets in the send queue of the gateway, sending delay can be avoided. | 09-12-2013 |
20140078931 | Wireless Communication Device, Wireless Communication System, And Wireless Communication Control Method - A wireless communication system is configured such that, during a period in which wireless communication is being performed between first and second wireless access points, wireless communication in a first wireless communication sub-network and a second wireless communication sub-network is made to stand by, and during the time other than the period in which wireless communication is being performed, wireless communication in at least one of the first wireless communication sub-network and the second wireless communication sub-network is performed. | 03-20-2014 |
20140293855 | WIRELESS COMMUNICATION SYSTEM AND WIRELESS ROUTER - In an ad-hoc wireless communication system, when there occurs a disparity in the remaining amounts of the batteries of wireless routers, it is impossible for each wireless router to change a communication route by itself. As proposed herein, in an invented multi-hop wireless network for communication via a plurality of routers, a wireless router operating intermittently changes its intermittent operation interval depending on its circumstances by its own judgment. | 10-02-2014 |