Abstract: A detection device configured to detect an object includes a first light source configured to emit infrared as first light in a first direction, a second light source configured to emit second light in a second direction different from the first direction, a shield to shield a portion of an optical path from the second light source, to allow a portion of the second light to pass, a light-receiving device configured to receive the first light reflected from the object and the portion of the second light reflected from the object, and circuitry configured to detect presence or absence of the object based on reception of reflected light by the detector. The second light is different from the first light.

Abstract: A detection apparatus for detecting an object, the detection apparatus includes a housing having an inner surface whose reflectance is equal to or lower than a certain value; an emitter configured to emit infrared rays into the housing; a sensor configured to detect infrared rays; and one or more processors configured to adjust an intensity of reflected infrared rays according to a result of detection by the sensor.

Abstract: A detection device configured to detect an object includes a first light source configured to emit infrared as first light in a first direction, a second light source configured to emit second light in a second direction different from the first direction, a shield to shield a portion of an optical path from the second light source, to allow a portion of the second light to pass, a light-receiving device configured to receive the first light reflected from the object and the portion of the second light reflected from the object, and circuitry configured to detect presence or absence of the object based on reception of reflected light by the detector. The second light is different from the first light.

Abstract: A communication apparatus for performing communication of a plurality of pieces of data includes a plurality of communication units configured to perform communication at frequencies different from each other; and a selection unit configured to select a physical position of electromagnetic wave radiation for each of the communication units, and switch the physical position to be selected to another one of the physical positions of the communication units at predetermined intervals.

Abstract: A wireless communications device includes an intent value storage configured to store therein an intent value indicating a level of intention to serve as an access point specified based on a certain criterion; a power supply status information storage configured to store therein a piece of power supply status information indicating whether power is supplied to the wireless communications device from an alternating-current power supply; and an access point determination unit configured to determine, between the wireless communications device and another wireless communications device forming the wireless network, one of the wireless communications devices as the access point. The determination unit is configured to acquire the intent value and the piece of power supply status information of the another wireless communications device, and determine the access point based on both of the intent values and both of the pieces of power supply status information.

Abstract: A wireless communication terminal includes an antenna selecting unit that selects, for each packet, an antenna for use in receiving signals from among a plurality of a plurality of antennas; a packet-destination judging unit that judges whether a packet obtained by demodulating a signal received by the receiving antenna selected by the antenna selecting unit is destined for the wireless communication terminal; and a stand-by-antenna determining unit that determines a stand-by antenna for use in receiving a packet to be received next based on a result of selection made by the antenna selecting unit and a result of judgment made by the packet-destination judging unit.

Abstract: A communication apparatus for performing communication of a plurality of pieces of data includes a plurality of communication units configured to perform communication at frequencies different from each other; and a selection unit configured to select a physical position of electromagnetic wave radiation for each of the communication units, and switch the physical position to be selected to another one of the physical positions of the communication units at predetermined intervals.

Abstract: A communication device is provided with a partial Fourier transformation circuit that calculates a correction parameter for quadrature errors correction. The partial Fourier transformation circuit is programmed to calculate a single one of frequency bins.

Abstract: A wireless communications device includes an intent value storage configured to store therein an intent value indicating a level of intention to serve as an access point specified based on a certain criterion; a power supply status information storage configured to store therein a piece of power supply status information indicating whether power is supplied to the wireless communications device from an alternating-current power supply; and an access point determination unit configured to determine, between the wireless communications device and another wireless communications device forming the wireless network, one of the wireless communications devices as the access point. The determination unit is configured to acquire the intent value and the piece of power supply status information of the another wireless communications device, and determine the access point based on both of the intent values and both of the pieces of power supply status information.

Abstract: A wireless communication terminal includes an antenna selecting unit that selects, for each packet, an antenna for use in receiving signals from among a plurality of a plurality of antennas; a packet-destination judging unit that judges whether a packet obtained by demodulating a signal received by the receiving antenna selected by the antenna selecting unit is destined for the wireless communication terminal; and a stand-by-antenna determining unit that determines a stand-by antenna for use in receiving a packet to be received next based on a result of selection made by the antenna selecting unit and a result of judgment made by the packet-destination judging unit.

Abstract: Orthogonal converters perform orthogonal conversion on the N time-series data extracted from a received radio signal. Multi-user detectors extract transmitted signals from respective transmission devices, from the time-series data which has been subjected to the orthogonal conversion. Inverse orthogonal converters perform inverse orthogonal conversion on the extracted transmitted signal. Rectangular filter circuits remove Mh time-series data at the front end and Mt time-series data at the rear end, from the transmitted signal which has been subjected to the inverse orthogonal conversion, so as to extract Nw time-series data. Deinterleaver circuits deinterleave the aforementioned time-series data. Decoders decode the time-series data for output.

Abstract: Orthogonal converters perform orthogonal conversion on the N time-series data extracted from a received radio signal. Multi-user detectors extract transmitted signals from respective transmission devices, from the time-series data which has been subjected to the orthogonal conversion. Inverse orthogonal converters perform inverse orthogonal conversion on the extracted transmitted signal. Rectangular filter circuits remove Mh time-series data at the front end and Mt time-series data at the rear end, from the transmitted signal which has been subjected to the inverse orthogonal conversion, so as to extract Nw time-series data. Deinterleaver circuits deinterleave the aforementioned time-series data. Decoders decode the time-series data for output.

Abstract: A communication device is provided with a partial Fourier transformation circuit that calculates a correction parameter for quadrature errors correction. The partial Fourier transformation circuit is programmed to calculate a single one of frequency bins.

Abstract: A DSSS and OFDM two-way waiting reception method is disclosed. The reception method includes the steps of (a) maintaining a two-way waiting state if none of an RSSI trigger, an OFDM search trigger, and a DSSS search trigger is generated; (b) switching to an RSSI-activated OFDM reception state if the RSSI trigger is generated in the two-way waiting state; (c) switching to a DSSS reception state if an OFDM synchronization loss trigger is generated in the RSSI-activated OFDM reception state; (d) switching to an OFDM search-activated OFDM reception state if the OFDM search trigger is generated in the two-way waiting state; (e) switching to the DSSS reception state if the DSSS search trigger is generated and the OFDM synchronization loss trigger is generated in the OFDM search-activated OFDM reception state; and (f) switching to the DSSS reception state if the DSSS search trigger is generated in the two-way waiting state.

Abstract: A wireless LAN apparatus is disclosed that includes a module group section that is connected to an upper level CPU of an upper level apparatus, an RF processing part that is connected to the module group section, a power reduction instruction dispatching section for dispatching a power reduction instruction, a power reduction instruction receiving section for receiving the power reduction instruction dispatched from the power reduction instruction section, and a power reduction sequence controlling section for controlling power of the module group section in a predetermined order in accordance with the power reduction instruction dispatched by the power reduction instruction dispatching section.

Abstract: An echo canceller includes: an echo cancellation part canceling echo included in a near-end input signal; a noise suppression part employing a low-pass filter having a variable cut-off frequency adaptive to power of an input signal, the noise suppression part removing a residual echo component from an output of the echo canceller part; a threshold generation part generating a variable threshold varying in accordance with a power level of a far-end input signal; a determination part making a determination based on a comparison between a power level of the output of the echo cancellation part and the variable threshold; and a processing part performing noise suppression using the low-pass filter on the output of the echo cancellation part when the determination part determines that the power level of the output of the echo cancellation part is lower than or equal to the variable threshold.

Abstract: A DSSS and OFDM two-way waiting reception method is disclosed. The reception method includes the steps of (a) maintaining a two-way waiting state if none of an RSSI trigger, an OFDM search trigger, and a DSSS search trigger is generated; (b) switching to an RSSI-activated OFDM reception state if the RSSI trigger is generated in the two-way waiting state; (c) switching to a DSSS reception state if an OFDM synchronization loss trigger is generated in the RSSI-activated OFDM reception state; (d) switching to an OFDM search-activated OFDM reception state if the OFDM search trigger is generated in the two-way waiting state; (e) switching to the DSSS reception state if the DSSS search trigger is generated and the OFDM synchronization loss trigger is generated in the OFDM search-activated OFDM reception state; and (f) switching to the DSSS reception state if the DSSS search trigger is generated in the two-way waiting state.

Abstract: In a wireless communication system formed by a plurality of access points constituting a wireless network, through which user terminals make accesses, and at least one control station configured to control the access points, public access points are systematically set up by a manager of the control station, while user's personal access points to be freely set up by users at desired locations according to needs of users are accommodated by operating the control station to measure a utilization level of each user's personal access point and charge an owner of each user's personal access point according to a measured utilization level and set up relay routes using the public access points and the user's personal access points.

Abstract: A wireless LAN apparatus is disclosed that includes a module group section that is connected to an upper level CPU of an upper level apparatus, an RF processing part that is connected to the module group section, a power reduction instruction dispatching section for dispatching a power reduction instruction, a power reduction instruction receiving section for receiving the power reduction instruction dispatched from the power reduction instruction section, and a power reduction sequence controlling section for controlling power of the module group section in a predetermined order in accordance with the power reduction instruction dispatched by the power reduction instruction dispatching section.

Abstract: An echo canceller includes: an echo cancellation part canceling echo included in a near-end input signal; a noise suppression part employing a low-pass filter having a variable cut-off frequency adaptive to power of an input signal, the noise suppression part removing a residual echo component from an output of the echo canceller part; a threshold generation part generating a variable threshold varying in accordance with a power level of a far-end input signal; a determination part making a determination based on a comparison between a power level of the output of the echo cancellation part and the variable threshold; and a processing part performing noise suppression using the low-pass filter on the output of the echo cancellation part when the determination part determines that the power level of the output of the echo cancellation part is lower than or equal to the variable threshold.