摘要:
A radio (102) in a sensor network and powered by electricity includes a data communicating unit (114) performing data communication; and a pulse interval demodulating unit (111) configured to (i) detect, from a signal (11c) with signals for corresponding frequency channels overlapped, a frequency channel indicated by a time interval between two pulses in a wake-up signal (1R) included in one of the frequency channels and (ii) cause the data communicating unit (114) to perform the data communication over the detected frequency channel.
摘要:
A radio (102) in a sensor network and powered by electricity includes a data communicating unit (114) performing data communication; and a pulse interval demodulating unit (111) configured to (i) detect, from a signal (11c) with signals for corresponding frequency channels overlapped, a frequency channel indicated by a time interval between two pulses in a wake-up signal (1R) included in one of the frequency channels and (ii) cause the data communicating unit (114) to perform the data communication over the detected frequency channel.
摘要:
An AGC unit starts a gain control of the variable gain amplifying unit when a bit saturation occurs in the digital baseband signal output from the A/D converting unit, and starts a gain control of the variable gain amplifying unit when a detection of STS from the digital baseband signal output from the A/D converting unit is started. The AGC unit performs the gain control of the variable gain amplifying unit once when the detection of STS is started, and performs the gain control of the variable gain amplifying unit twice when the bit saturation occurs, namely a larger number of times than when the detection of STS is started.
摘要:
A base station includes: an estimation section estimating transmission condition of each of frequency channels used for communication; a reception section receiving a data signal from each communication terminal through any of the frequency channels; a measurement section measuring received signal power of the received data signal for each frequency channel; a determination section determining, for each frequency channel, whether the received data signal is demodulated errorlessly; and a control section assigning frequency channels estimated as being in good transmission condition by the estimation section, to communication terminals the data signals of which are determined as not being errorlessly demodulated by the determination section, such that a frequency channel in a better transmission condition is assigned preferentially to a communication terminal having larger received signal power detected by the detection section, and transmitting retransmission request signals requesting the communication terminals to retransmit the data signals using the assigned frequency channels.
摘要:
A transmission-reception device includes a radio frequency section that performs a frequency conversion on a signal which is modulated using a single carrier transmission system, a correction coefficient multiplier that multiplies a frequency domain signal by a distortion correction coefficient in the frequency conversion of the radio frequency section to correct a distortion, a first transformer that converts a time domain signal into a frequency domain signal at a time of reception, and converts the frequency domain signal which is distortion-corrected by the correction coefficient multiplier into a time domain signal at a time of transmission, and a second transformer that converts a time domain signal into a frequency domain signal at a time of transmission, and converts the frequency domain signal which is distortion-corrected by the correction coefficient multiplier into a time domain signal at a time of reception.
摘要:
The communication device (10) which performs, when attached to the first region of the moving body, wireless communication with the communication partner device (20) attached to the second region of the moving body includes: a motion obtaining unit (11) which obtains motion information indicating a motion of at least one region of the moving body; a parameter determining unit (12) which determines a parameter corresponding to the motion of the region of the moving body indicated by the motion information obtained by the motion obtaining unit (11), using parameter information in which the motion and a parameter indicating a communication mode for successful wireless communication are associated with each other; and a wireless communication unit (13) which performs wireless communication with the communication partner device (20) according to the parameter determined by the parameter determining unit (12).
摘要:
A transmission power controller turns on a power supply to a transmitter at a given time taking a power rise time into account before a start time of transmission processing in the transmitter, and turns off the power supply to the transmitter when the transmission processing is finished. A reception power controller turns on a power supply to a receiver at a given time taking a power rise time into account before a time at which an ACK is assumed to be arrival from a wireless communication device on a receiver side responsive to data transmitted from the transmitter, and turns off the power supply to the receiver when the reception processing of the ACK in the receiver is finished.
摘要:
In a wireless communication system according to the present invention: a control device and a communication terminal communicate in an active period. The control device: generates a first beacon packet including one or more candidate channels; transmits the first beacon packet at the beginning of the active period; determines whether or not a use channel is to be changed based on a communication state, and generates a second beacon packet including information of a determination result; transmits the second beacon packet at the end of the active period; and, when it is determined that the use channel is to be changed, changes the use channel after the active period ends and before a next active period starts. The communication terminal: receives the first and second beacon packets; and, based on the second beacon packet, changes the use channel after the active period ends and before a next active period starts.
摘要:
A correlation unit (32) sequentially obtains correlation values between a baseband signal and a reference signal and outputs the obtained reference signal to a section division unit (33). The output of the correlation unit (32) is divided into symbol time periods by the section division unit (33). A section position detection unit (34) detects a largest correlation value in each of sections resulting from the division by the correlation unit (32) and outputs, to a synchronization judgment unit (35), first position information that indicates a relative position of each detected largest correlation value. The synchronization judgment unit (35) detects an arrival of a packet signal and estimates a symbol timing based on the first position information of the sections.
摘要:
A base station includes: an estimation section estimating transmission condition of each of frequency channels used for communication; a reception section receiving a data signal from each communication terminal through any of the frequency channels; a measurement section measuring received signal power of the received data signal for each frequency channel; a determination section determining, for each frequency channel, whether the received data signal is demodulated errorlessly; and a control section assigning frequency channels estimated as being in good transmission condition by the estimation section, to communication terminals the data signals of which are determined as not being errorlessly demodulated by the determination section, such that a frequency channel in a better transmission condition is assigned preferentially to a communication terminal having larger received signal power detected by the detection section, and transmitting retransmission request signals requesting the communication terminals to retransmit the data signals using the assigned frequency channels.