Abstract: A receiving apparatus includes a variable gain unit to change between a first gain and a smaller second gain, and to amplify a received signal to obtain an amplified signal; a comparator to compare a power of the amplified signal with a reference value; and a controller to set a gain to the first gain while in a standby state, to reset a gain to a third gain between the first and second gains if in a standby state the power of the received signal is larger than the reference value, and then to set a gain to the first gain and return to the standby state if the power is equal to or lower than the reference value, or if not, to a fourth gain between the first and third gains.

Abstract: According to one embodiment, a wireless communication apparatus includes a transceiver, an estimator and a controller. The transceiver transmits and receives a frame in a frequency band which is used by a first system executing communication in a first communication range determined by a first transmission power and a first antenna gain. The estimator determines whether an amount of interference in the frequency band from a second system is no less than a threshold, the second system executing communication in a second communication range which is larger than the first communication range and which is determined by a second transmission power and a second antenna gain. The controller increases a transmission power when the amount of interference is no less than the threshold.

Abstract: A stationary proximity wireless communication apparatus has an electromagnetic-wave transmitting and receiving part comprising a first indicator that indicates a zone to place a portable proximity wireless communication apparatus and an antenna that is installed in the zone to emit electromagnetic waves having directivity in a direction of a recommended optimum position suitable to place the portable proximity wireless communication apparatus in the zone from a position different from the recommended optimum position, and a wireless communication part configured to perform modulation and demodulation processes of electromagnetic waves transmitted and received at the antenna.

Abstract: According to one embodiment, a wireless device is provided with a semiconductor chip, a substrate, an antenna, and a sealing material. The chip includes a wireless circuit. The substrate has a plurality of terminals arranged on a first surface and the chip arranged on a second surface. The antenna includes a radiation element and is electrically connected to the chip. The sealing material seals the chip and the antenna. A distance between a first wall of the sealing material substantially parallel to the second surface and the radiation element is equal to or more than a distance between a second wall of the sealing material substantially perpendicular to the second surface and the radiation element.

Abstract: According to one embodiment, a wireless communication apparatus using a first wireless communication scheme includes a transmitter and controller. The controller which controls IFSs so as to set, one of the first IFS and the second IFS as an IFS used during the first period. the controller sets the second IFS to at least a second period when a channel is idle during a period corresponding to a fourth IFS after one of the IFS is switched from the first IFS to the second IFS and when the channel becomes busy after the period corresponding to the fourth IFS is elapsed, the fourth IFS being an IFS before the transmission of a beacon signal, the second period being one of a plurality of first periods and being a period which includes timing for an estimated cycle of the beacon signal.

Abstract: According to an embodiment, a wireless communication device includes first and second wireless units. The first wireless unit includes a first reception antenna and a first transmission antenna in an enclosure, transmits a first wireless signal via the first transmission antenna, and receives a second wireless signal via the first reception antenna. The second wireless unit includes a second reception antenna and a second transmission antenna in the enclosure, transmits the second wireless signal via the second transmission antenna, and receives the first wireless signal via the second reception antenna. The first and second wireless units are disposed such that value of half distance between the first and second transmission antennas is smaller than value of a smaller one among a first shortest distance between the first transmission antenna and an inner wall of the enclosure, and a second shortest distance between the second transmission antenna and the inner wall.

Abstract: According to one embodiment, a wireless communication apparatus has a transmitter, a receiver, and a transmission timing instructor. The transmitter transmits a signal by using a first wireless communication scheme. The receiver receives a signal transmitted by using the first wireless communication scheme. The receiver detects a signal of which a frequency band includes at least a part of a frequency band used in the first wireless communication scheme, which is other than a signal transmitted by using the first wireless communication scheme. The transmission timing instructor instructs the transmitter to transmit a signal by using the first wireless communication scheme if the receiver does not receive a signal over a predetermined time from a detection of a signal other than a signal transmitted by using the first wireless communication scheme.

Abstract: According to one embodiment, a wireless communication apparatus includes a transceiver, an estimator and a controller. The transceiver transmits and receives a frame in a frequency band which is used by a first system executing communication in a first communication range determined by a first transmission power and a first antenna gain. The estimator determines whether an amount of interference in the frequency band from a second system is no less than a threshold, the second system executing communication in a second communication range which is larger than the first communication range and which is determined by a second transmission power and a second antenna gain. The controller increases a transmission power when the amount of interference is no less than the threshold.

Abstract: A wireless communication device has processing circuitry. The processing circuitry measures intensity of a signal received from a communication apparatus, senses whether the intensity is equal to or greater than a first threshold value, performs a connection process with the communication apparatus, performs data communication with the communication apparatus through close-range wireless communication, updates the first threshold value to the intensity and make a first sensor proceed with its process, senses whether a difference between the intensity and the first threshold value becomes larger than a second threshold value, and disconnects the communication with the communication apparatus when being sensed that the difference is larger than the second threshold value.

Abstract: The transmitter includes a first bit generator, a modulator, a second bit generator and a bit converter. The first bit generator generates bits to be transmitted based on the first wireless scheme. The modulator for the first wireless scheme performs at least amplitude modulation of a multiple level on the bits generated by the first bit generator. The second bit generator generates a bit to be transmitted based on the second wireless scheme. The bit converter converts the bit generated by the second bit generator and inputs converted bits to the modulator wherein the bit converter converts the bit generated by the second bit generator so that a signal showing High in the second wireless scheme is modulated to amplitude of a high level in the multiple level in the modulator.

Abstract: A stationary proximity wireless communication apparatus has an electromagnetic-wave transmitting and receiving part comprising a first indicator that indicates a zone to place a portable proximity wireless communication apparatus and an antenna that is installed in the zone to emit electromagnetic waves having directivity in a direction of a recommended optimum position suitable to place the portable proximity wireless communication apparatus in the zone from a position different from the recommended optimum position, and a wireless communication part configured to perform modulation and demodulation processes of electromagnetic waves transmitted and received at the antenna.

Abstract: According to one embodiment, a receiving apparatus includes a variable gain amplifier, comparator, and signal processor. The comparator compares a signal level of the second signal with a first threshold to generate a third signal, a signal level of the third signal being set to a high signal if the signal level of the second signal is greater than the first threshold. The signal processor determines presence of a signal if a rate of high signals in third signals for a period is greater than a second threshold. The second threshold is set to a first value when the control of the gain is performed and set to a second value when the demodulation processing is performed. The first value is greater than the second value.

Abstract: According to one embodiment, a communication device, which performs communication using a first communication method and a second communication method, converts information to be transmitted into information for forming a pulse that is formed depending on the presence and absence of transmission of a radio wave, according to the first communication method. The communication device decides a suppression time, during which communication with a communication device other than a communication partner is suppressed, on the basis of a result of the conversion. The communication device generates an output signal including the transmission suppression signal, in which the suppression time is set for each first element in the pulse, according to the second communication method, the first element transmitting a radio wave. The communication device transmits a radio wave according to the output signal to the communication partner at timing to transmit a radio wave in the pulse.

Abstract: A relay device is provided that includes a reception unit and a transmission unit. The reception unit receives a startup packet including a magic packet, a MAC address of controllable equipment, and a first ID for starting up the controllable equipment. The transmission unit transmits a first electric signal indicating the first ID to all link-downed Ethernet ports.

Abstract: According to one embodiment, a radio apparatus configured to communicate with a second radio apparatus after receiving plural first signals transmitted from the second radio apparatus in a constant cycle, the radio apparatus includes: a communication circuit configured to communicate with the second radio apparatus; a wave detection circuit configured to generate a wave detection signal by envelope-detecting the plural first signals; a bandpass filter having an IIR filter, configured to generate a detection signal form the wave detection signal, the detection signal having amplitude is increased at a frequency corresponding to the constant cycle; and a control unit configured to cause supply of power to the communication circuit if the amplitude is larger than a first threshold value.

Abstract: An electronic system includes: an AC-DC converter to convert an AC voltage into a DC voltage and to supply the DC voltage to a secondary battery; a first detector to detect a remaining amount of the secondary battery; a transmitter to transmit a signal corresponding to the remaining amount of the secondary battery; a receiver to receive the signal transmitted by the transmitter; and a controller to control the AC-DC converter using the signal received by the receiver.

Abstract: A large amount of user information is transmitted with good efficiency by means of a high-speed downlink by making transmission rates of an uplink circuit and a downlink asymmetrical. The radio communication system includes a plurality of base stations, a plurality of terminals, an uplink established between each of the base stations and each of the terminals for the purpose of radio transmission of prescribed information from a terminal to a base station, and a downlink circuit established between each of the terminals and each of the base station for the purpose of radio transmission of prescribed data from a base station to a terminal.

Abstract: A large amount of user information is transmitted with good efficiency by means of a high-speed downlink by making transmission rates of an uplink circuit and a downlink asymmetrical. The radio communication system includes a plurality of base stations, a plurality of terminals, an uplink established between each of the base stations and each of the terminals for the purpose of radio transmission of prescribed information from a terminal to a base station, and a downlink circuit established between each of the terminals and each of the base station for the purpose of radio transmission of prescribed data from a base station to a terminal.

Abstract: A large amount of user information is transmitted with good efficiency by means of a high-speed downlink by making transmission rates of an uplink circuit and a downlink asymmetrical. The radio communication system includes a plurality of base stations, a plurality of terminals, an uplink established between each of the base stations and each of the terminals for the purpose of radio transmission of prescribed information from a terminal to a base station, and a downlink circuit established between each of the terminals and each of the base station for the purpose of radio transmission of prescribed data from a base station to a terminal.

Abstract: A large amount of user information is transmitted with good efficiency by means of a high-speed downlink by making transmission rates of an uplink circuit and a downlink asymmetrical. The radio communication system includes a plurality of base stations, a plurality of terminals, an uplink established between each of the base stations and each of the terminals for the purpose of radio transmission of prescribed information from a terminal to a base station, and a downlink circuit established between each of the terminals and each of the base station for the purpose of radio transmission of prescribed data from a base station to a terminal.