Abstract: A wireless circuit (100) which is capable of simultaneously outputting a plurality of transmission signals, including: a transmission signal selection circuit (31) which selectively outputs a detecting object signal out of a plurality of transmission signals; and a detection circuit (33) which detects a power of the detecting object signal thus outputted. This enables to provide, by use of a compact configuration, a technique for individually detecting transmission signals which are simultaneously generated by a respective plurality of transmission circuits.

Abstract: A wireless circuit (100) which is capable of simultaneously outputting a plurality of transmission signals, including: a transmission signal selection circuit (31) which selectively outputs a detecting object signal out of a plurality of transmission signals; and a detection circuit (33) which detects a power of the detecting object signal thus outputted. This enables to provide, by use of a compact configuration, a technique for individually detecting transmission signals which are simultaneously generated by a respective plurality of transmission circuits.

Abstract: A dual-mode cellular telephone system which is capable of suppressing a narrow-band disturbing signal appearing in a mobile station of a dual-mode cellular telephone system adapted for both an analog system and a digital CDMA system. A CDMA signal from a CDMA base station, and a narrow-band signal from an analog system are received through an antenna by a receiver, whereby they are amplified, subjected to frequency conversion, and input to a variable notch filter. A disturbing signal detection circuit supplies the variable notch filter with a control signal for varying its frequency. Namely, the disturbing signal detection circuit detects a case that an output level of the variable notch filter is at a minimum by changing the notch frequency via a series of sweeping control signals. A control signal at which the output level of the variable notch filter is at a minimum is then fed to the variable notch filter, thereby effectively suppressing any intermodulation distortions present in the mobile station.

Abstract: A transponder used in a remote identification system requiring an interrogator and a transponder. The transponder which is thin and compact includes a transmit/receive antenna which is thin for receiving an interrogating signal and a rewrite signal emitted from the interrogator, and for emitting a response signal towards the interrogator. There is a modulator/demodulator for modulating a signal according to a code inherent in the transponder to emit the same from the antenna as the response signal without newly applying energy to the interrogating signal, and for demodulating the rewrite signal. A controller for applying a modulating signal generated according to the inherent code to the modulator/demodulator and for storing a signal demodulated by the modulator/demodulator. A liquid crystal display is used for displaying data including bar codes which can be read by a bar code reader. The bar code can be rewritten.

Abstract: A detachable IC card applicable to a portable data processing device referred to as an "electronic organizer" is disclosed. The IC card is formed of microstrip lines formed on a dielectric substrate. An antenna receives an externally applied unmodulated carrier signal and guides the received signal to microstrip lines for impedance conversion. Cathode potential of a diode is varied in response to a data signal outputted from a CPU, so that the barrier capacitance of the diode varies. Accordingly, the carrier is reflected according to the data signal and radiated toward the electronic organizer main body through the antenna. An oscillator for data transmission is not required in the IC card, so that an internal battery having a large capacitance is not required, either. As a result, without increasing the size and weight of the device, radio transmission of data from the IC card can be accomplished.

Abstract: The SSB modulator according to the present invention is comprised of a driving voltage generator, a diode, a bias supply circuit, an impedance transformation circuit and an input/output terminal. The SSB modulator is arranged such that the impedance of the diode is changed by changing the driving voltage impressed across the diode, resulting in the mismatching of the impedance, which leads to generation of a reflected wave. Therefore, by changing the amplitude and the phase of the above-obtained reflected wave, SSB modulation is effected. Accordingly, the SSB modulator of the present invention, requiring no particular side band filter, is compact in size, light in weight and low in manufacturing cost, with a simple structure of the circuit.