Abstract: There are provided a plurality of radio devices detecting an interference source signal transmitted by an interference source and generating pieces of air time information showing whether the interference source signal exists or not for each predetermined time unit; and an aggregation device estimating air time of the interference source by acquiring the pieces of air time information from the plurality of radio devices and aggregating/integrating the acquired pieces of air time information for each predetermined unit time, matching timings.

Abstract: A plurality of access points configured to communicate with a subordinate wireless LAN terminal, an information collecting device configured to collect a frame respectively transmitted and received between the plurality of access points and the wireless LAN terminal, and extract information on communication quality of an access point of the plurality of access points from a header of the frame, and an information collecting server configured to acquire the information on the communication quality of the access point from the information collecting device, analyze the information to determine whether the communication quality is good or bad for each of the plurality of access points, and execute processing of externally displaying or notifying a result that is determined are included.

Abstract: A biological detection device includes a signal acquirer that acquires a signal including a heartbeat, an analyzer that performs a frequency analysis of the signal to generate a spectrogram, an integrated value calculator that integrates energy of a heartbeat frequency component, which is a frequency component corresponding to the heartbeat, among frequency components of the signal shown by the spectrogram and calculates an integrated value, a peak specifier that specifies peaks, which are maximum values, in the integrated value, a peak set generator that combines, among the peaks, a first peak and a second peak, which occurs in a later time than the first peak, and generates a peak set, and a selector that selects, from the peak set, a sequence having highest likelihood in a maximum likelihood estimation method.

Abstract: A biological detection device includes a signal acquirer that acquires a signal including a respiration component, a filter that attenuates a frequency component other than the respiration component included in the signal and generates a post-processing signal, an analyzer that analyzes the post-processing signal to generate a spectrogram, a variation calculator that calculates variation of energy in a predetermined frequency band in energy of the frequency component indicated by the spectrogram, a first determiner that determines whether the variation is larger than a threshold, a second determiner that, if it is determined by the first determiner that the variation is not larger than the threshold, determines whether a higher harmonic wave with respect to a second peak having energy equal to or more than a predetermined ratio to a first peak where the energy is maximum is present in the predetermined frequency band, and an output unit that outputs a respiration rate based on a frequency of the first peak if

Abstract: An object is to accurately detect abnormality of a living body.

Abstract: A signal representing heartbeat behavior is accurately restored. The present signal restoration system includes: a signal acquirer configured to acquire a first heartbeat signal representing heartbeat behavior; a first band-pass filter configured to generate a first signal by performing first band-pass filter processing on the first heartbeat signal; an integral calculator configured to calculate an integral value by integrating frequency intensity of the heartbeat represented by the first signal; a second band-pass filter configured to generate a third signal by performing second band-pass filter processing on a second signal representing the integral value with respect to time; and a restored signal generator configured to generate a restored signal representing heartbeat behavior based on first data generated by dividing the third signal at intervals of a predetermined time.

Abstract: An object is to accurately determine the presence or absence of a living body. A living body detection device comprises: a signal acquirer that acquires a first signal including a first frequency component that is a frequency component of heartbeat and a second frequency component that is a frequency component of breathing; a filter that attenuates a frequency component higher than the first frequency component based on the first signal to generate a second signal; a frequency analyzer that analyzes a frequency component of the second signal; a variance value calculator that calculates a first variance value of energy of at least one of the first frequency component and the second frequency component based on a result of analysis by the frequency analyzer; a first statistical quantity calculator that calculates a first statistical quantity of the first variance value for a predetermined period; and a determiner that determines presence or absence of a living body based on the first statistical quantity.

Abstract: An activity recognition system for identification of an activity of a subject includes a transmitter configured to transmit a radio wave, a receiver configured to receive the radio wave by an array antenna, a feature quantity extracting part configured to extract a feature quantity from a signal received by the array antenna, and an identifying part configured to identify the activity based on the feature quantity, wherein the feature quantity extracting part is configured to calculate a first feature quantity that represents a change of the signal by using a signal received at an observation start time point as a reference signal and to calculate a second feature quantity that represents a change of the signal by using an immediately preceding signal as a reference signal, and the identifying part is configured to identify the activity based on the first feature quantity and the second feature quantity.

Abstract: An activity recognition system for identification of an activity of a subject includes a transmitter configured to transmit a radio wave, a receiver configured to receive the radio wave by an array antenna, a feature quantity extracting part configured to extract a feature quantity from a signal received by the array antenna, and an identifying part configured to identify the activity based on the feature quantity, wherein the feature quantity extracting part is configured to calculate a first feature quantity that represents a change of the signal by using a signal received at an observation start time point as a reference signal and to calculate a second feature quantity that represents a change of the signal by using an immediately preceding signal as a reference signal, and the identifying part is configured to identify the activity based on the first feature quantity and the second feature quantity.

Abstract: A heartbeat detection system includes a Doppler sensor configured to receive a reflective wave from a subject, to obtain a Doppler signal; and a processor including a memory and a CPU. The processor executes applying a wavelet transform to the Doppler signal based on a plurality of scale factors, to obtain a wavelet coefficient for each of the scale factors; detecting a plurality of peaks of the wavelet coefficient for each of the scale factors; calculating each peak interval between the peaks next to each other, and each difference between the peak intervals next to each other, for each of the scale factors; selecting one of the scale factors that has a minimum variation in the differences of the peak intervals, as an optimal scale factor; and measuring the peak intervals calculated based on the optimal scale factor as heartbeat intervals.

Abstract: Conventionally, if the number of transmission antennas is greater than that of reception antennas, different signals simultaneously transmitted from the transmission antennas cannot be separated from one another at the receiving end, resulting in a significant degradation of received-signal quality. A transmitter and a receiver each have a plurality of antennas. The transmitter transmits a pilot signal. The receiver receives the pilot signal, calculates transmission-related information corresponding to the pilot signal, selects, based on this calculated information, a transmission signal to be used by the transmitter, and notifies the transmitter of the selected signal. The transmitter selects, from the informed transmission signal, transmission antennas and uses the selected antennas to transmit information signals, so that a signal separation can be easily performed at the receiving end.

Abstract: Conventionally, if the number of transmission antennas is greater than that of reception antennas, different signals simultaneously transmitted from the transmission antennas cannot be separated from one another at the receiving end, resulting in a significant degradation of received-signal quality. A transmitter and a receiver each have a plurality of antennas. The transmitter transmits a pilot signal. The receiver receives the pilot signal, calculates transmission-related information corresponding to the pilot signal, selects, based on this calculated information, a transmission signal to be used by the transmitter, and notifies the transmitter of the selected signal. The transmitter selects, from the informed transmission signal, transmission antennas and uses the selected antennas to transmit information signals, so that a signal separation can be easily performed at the receiving end.

Abstract: A radio communication method and apparatus generate a plurality of information signals and transmit the signals to a communication partner from a plurality of antennas. A plurality of combination of signals to be transmitted are selected. A transmission evaluation value is determined based on the signal noise ratio of each signal. After all combinations are evaluated, a transmission format suitable for sending a combination of signals is determined based on a highest evaluation value.

Abstract: Conventionally, if the number of transmission antennas is greater than that of reception antennas, different signals simultaneously transmitted from the transmission antennas cannot be separated from one another at the receiving end, resulting in a significant degradation of received-signal quality. A transmitter and a receiver each have a plurality of antennas. The transmitter transmits a pilot signal. The receiver receives the pilot signal, calculates transmission-related information corresponding to the pilot signal, selects, based on this calculated information, a transmission signal to be used by the transmitter, and notifies the transmitter of the selected signal. The transmitter selects, from the informed transmission signal, transmission antennas and uses the selected antennas to transmit information signals, so that a signal separation can be easily performed at the receiving end.

Abstract: Conventionally, if the number of transmission antennas is greater than that of reception antennas, different signals simultaneously transmitted from the transmission antennas cannot be separated from one another at the receiving end, resulting in a significant degradation of received-signal quality. A transmitter and a receiver each have a plurality of antennas. The transmitter transmits a pilot signal. The receiver receives the pilot signal to calculate transmission-related information corresponding to the pilot signal, and then selects, based on this calculated information, a signal to be sent to and utilized by the transmitter. The receiver then informs the selected signal to the transmitter. The transmitter selects, from the informed signal, transmission antennas and uses them to transmit information signals, so that a signal separation can be easily performed at the receiving end.