Abstract: A power supply system capable of supplying power from a power transmitter to a power receiver in an electrically non-contact manner, in which a power transmission module is attached to the power transmitter and a power reception module is attached to the power receiver. The power transmission module has a plurality of transmission-side coils for transmitting power and a plurality of transmission-side switches for turning on/off operation of the transmission-side coils. The power reception module has a plurality of reception-side coils for receiving power, a plurality of reception-side switches for turning on/off operation of the reception-side coils and, further, has a determination circuit for performing control so as to operate any of the transmission-side coils and any of the reception-side coils in a combination realizing highest power transmission efficiency.

Abstract: A read-write processing apparatus communicates with an RFID tag provided with a semiconductor memory to exchange commands and responses through antenna coils. A condition under which only a carrier wave is transmitted is set prior to a communication with the RFID tag and a level from a reception signal obtained under this condition is extracted as noise level. The extracted noise level is displayed or outputted to an output host apparatus.

Abstract: A method and apparatus are provided to generate calibration signals to multiple stages in a receiver channel. The multiple stages are calibrated using multiple calibration circuits, where a controller controls each calibration circuit. The controller is coupled to the output of the final stage in the receiver channel through a single comparison unit. The output from the single comparison unit is used by the controller to calibrate each of the multiple stages.

Abstract: An improved directional coupler that significantly reduces the signal degradation problems associated with distortion caused by circuit elements used to measure the transmitted power. In a selected embodiment, the directional coupler of the present invention comprises a plurality of active elements, such as capacitors, that have values selected to ensure that the distortion created by circuit elements used to measure forward transmitted power. In an embodiment of the invention, capacitors have values selected to minimize in-band distortion signals at the fundamental carrier frequency of the transmitted signal and also at the second and third harmonics of the fundamental carrier frequency.

Abstract: A wireless communication device includes a removable panel (100), a base cover (200) and a latching assembly (300). The removable panel has a first mounting portion (120). The base cover has a second mounting portion (240) corresponding to the first mounting portion of the removable panel. The latching assembly includes a lacking fastener (320) and a coil spring (340), wherein the latching assembly is effective to nail the removable panel into the housing through the first mounting portion and the second mounting portion. Therefore, it is simple, tight and easy for current invention using the latching assembly to fix the removable panel to the base cover, or to disassemble the removable panel away.

Abstract: In a radio communication system having a phase control loop for phase modulation and an amplitude control loop for amplitude modulation and being capable of time divisional transmission and reception under a predetermined time management, when transmission in a first mode is switched to transmission in a second mode or when transmission in the second mode is switched to transmission in the first mode, the output level of the power amplifier is lowered once to a predetermined level higher than the level when transmission related circuits are activated, and thereafter the output level of the power amplifier is again ramped after the settings have been changed but without starting of a transmission oscillator, establishing of the phase control loop and the amplitude control loop.

Abstract: A low-noise differential bias circuit is provided which obtains excellent noise characteristics while ensuring excellent distortion characteristics. A collector of a transistor Q11 is connected to a voltage supply point (Vcc) via a resistor R15. A base of the transistor Q11 is connected to a base of a transistor Q1 via resistors R13, R11 connected in series. A connection point between the resistors R11, R13 is connected to the collector of the transistor Q11. A collector of a transistor Q12 is connected to the voltage supply point at connection point A via a resistor R16. A base of the transistor Q12 is connected to a base of a transistor Q2 via resistors R14, R12 connected in series. A connection point between the resistors R12, R14 is connected to the collector of the transistor Q12. By this configuration, a high frequency ground is performed at the connection point A.

Abstract: A frequency synthesizer for use in a transceiver generates a relatively high reference frequency with fine frequency resolution and low in-band phase noise by using a digital processor to generate a digital reference signal at a finely-tuned reference frequency. A Digital-to-Analog Converter (DAC) converts the digital reference signal to an analog reference signal, and a low pass filter filters the analog reference signal to produce a filtered analog reference signal. The frequency synthesizer further includes a phase locked loop for up-converting the filtered analog reference signal from an IF signal to an RF signal.

Abstract: A Base Station (BS) apparatus for estimating a velocity of a Mobile Station (MS) in a mobile communication system includes a channel estimator for performing channel estimation according to a velocity band, receiving a wireless channel signal from the MS, and performing channel estimation using channel estimation coefficients optimized for individual velocity bands; and a velocity estimator for dividing the velocity band into a plurality of sub-Doppler bands, detecting a sub-Doppler band including a frequency index having a maximum frequency response from among the divided sub-Doppler bands, and transmitting information of the detected sub-Doppler band to the channel estimator such that a channel estimation coefficient corresponding to the information is transmitted.

Abstract: A communication apparatus (100), when synchronization of a received signal is established, performs transmit power control using a transmit power value obtained by closed-loop transmit power control by a transmit power control circuit (201), and when the synchronization of the received signal is out, controls a current transmit power value to gradually return over a predetermined period to a transmit power value determined at a timing closest to the current timing from among past reliable transmit power values determined when the synchronization was established.

Abstract: A communication system for a mobile platform satellite service (MPSS) system includes a receiver subsystem (RS) and a transmitter subsystem (TS). A satellite transponder is in communication with the RS and the TS of the mobile platform. A satellite service ground station includes a transmitter subsystem (TS) and a receiver subsystem (RS). A communication link is established between the MPSS system and the ground station, via the satellite transponder. The communications link includes fixed satellite service (FSS) data superimposed on MPSS data in the same frequency band to thereby maximize both satellite transponder utilization and interference budget usage.

Abstract: A tire air pressure detection system, able to prevent a strong electric field or strong radio interference from affecting transmitters and causing mistaken data relating to tire air pressure to be sent out and a driver from being mistakenly warned, having transmitters with controllers, detection circuits, and sensing units and a receiver, the controllers stopping detection signals from being sent to the receiver at current transmission timings when the detection circuits detect a strong electric field or radio interference in the interval from a previous communication timing to a current communication timing, whereby even if the strong electric field or radio interference affects detection signals from sensors provided at the sensing units, the transmitters can be prevented from sending out mistaken data relating to tire air pressure.

Abstract: A base station having at least one reception antenna generates a reception beam using a previous reception beam weight and a despread signal of a current reception signal, calculates an error value indicating a difference between the current reception signal and a desired reception signal, and calculates a current reception beam weight using the previous reception beam weight, the despread signal and the error value. The base station generates a reception beam weight step value using the error value and an output signal, calculates a difference between the previous reception beam weight and a product of the reception beam weight step value, the despread signal, and a conjugate value of the error value, as the current reception beam weight, and selects the reception beam weight step value such that the current reception beam weight becomes the optimal reception beam.