摘要:
An amplifier circuit includes a high-gain amplifier, and a feedback circuit for extracting an unstable output having a level equal to or less than a threshold level from an amplified signal from the amplifier and for feeding back the unstable signal to the amplifier, so that the amplifier oscillates at a predetermined oscillation frequency. The amplifier circuit also includes a band rejection filter for passing signal components of the amplified signal other than an oscillation output which is obtained at the output terminal of the amplifier when the amplifier oscillates at the predetermined oscillation frequency. The signal components obtained from the band rejection filter are an output signal of the amplifier circuit.
摘要:
A constant-amplitude wave combination type amplifier includes a first amplifier outputting a first amplified output, and a second amplifier outputting a second amplified output. The constant-amplitude wave combination type amplifier also includes a first constant-amplitude wave generating circuit for combining an input wave and the second amplified output from the second amplifier and for generating a first constant-amplitude wave which is input to the first amplifier, and a second constant-amplitude wave generating circuit for combining the input wave and the first amplified output from the first amplifier and for generating a second constant-amplitude wave. Further, the constant-amplitude wave combination type amplifier includes a wave combining circuit for combining the first and second constant-amplitude waves and for generating an output wave.
摘要:
A high frequency amplifier containing: a constant envelope signal generation circuit for transforming an input signal to form two constant envelope signals where phases of the constant envelope signals correspond to an amplitude of an envelope of the input signal; two amplifying circuits for separately amplifying two constant envelope signals; and a power synthesizing circuit for synthesizing the first and second amplified signals to generate an amplified signal of the input electric signal, and reflecting remaining components of the first and second amplified signals which remaining components remain in the above synthesizing operation, toward the first and second amplifying circuits. Further, an input impedance of the power synthesizing circuit may be controlled by shifting phases of the above reflected components by respectively predetermined amounts, or by adaptively shifting phases of the above reflected components responding to an input level, so that a total efficiency of the high frequency amplifier is maximized. The high frequency amplifier may contain, instead of the above two amplifying circuits and the power synthesizing circuit, a circuit for inverting a phase of one of the two constant envelope signals; and a single-ended push-pull amplifier circuit for receiving the other of the two constant envelope signals, and an output of the phase inversion circuit, and synthesizing the received signals to generate an amplified signal of the input electric signal.
摘要:
A linear amplifier for amplifying a composite signal of plural frequency components to improve high efficiency without lowering the efficiency of a power load, includes a nonlinear amplifier circuit to which a signal having plural different frequency components is inputted, a 2nd-order distortion arithmetic circuit for generating and outputting a 2nd-order distortion component of the signal having the plural different frequency components, and an injection unit for injecting the 2nd-order distortion component to the signal having plural different frequency components. The nonlinear amplifier amplifies the signal injected with the 2nd-order distortion component.
摘要:
An apparatus performing wireless communication with a group of a plurality of base station antennas disposed on a wireless base station apparatus side in accordance with a multi-input multi-output wireless communication system includes a group of a plurality of repeater antennas disposed around the body of a user. The apparatus further includes a repeater base apparatus being connected to the group of the repeater antennas, communicating, with a handheld mobile terminal apparatus carried by the user, transmission/reception data in the handheld mobile terminal apparatus in accordance with a short-distance wireless communication system, and communicating, between the group of the plurality of the repeater antennas and the group of the base station antennas, the transmission/reception data in accordance with the multi-input multi-output wireless communication method.
摘要:
An RFID tag having a tag antenna and an LSI chip, comprising: a power-supply pattern on which the LSI chip is mounted; a patch antenna that functions as the tag antenna; and a high-frequency connection section that makes a high-frequency connection between the power-supply pattern and the patch antenna. The high-frequency connection section is formed, for example, by forming a slot in the patch antenna, layering one end of a small dipole antenna that functions as the power-supply pattern over the slot so that it crosses over the slot, and supplying power from the small dipole antenna to the patch antenna.
摘要:
A wireless frequency tag includes a loop-shaped antenna pattern that is electrically connected to a chip connecting section, and a conducting member that electrically couples a part of the antenna pattern.
摘要:
An RFID tag having a tag antenna and an LSI chip, comprising: a power-supply pattern on which the LSI chip is mounted; a patch antenna that functions as the tag antenna; and a high-frequency connection section that makes a high-frequency connection between the power-supply pattern and the patch antenna. The high-frequency connection section is formed, for example, by forming a slot in the patch antenna, layering one end of a small dipole antenna that functions as the power-supply pattern over the slot so that it crosses over the slot, and supplying power from the small dipole antenna to the patch antenna.
摘要:
A wireless tag adapted for mounting inside a hollow electrically conductive pipe, includes: a contact placed in contact with the electrically conductive pipe so as to be electrically connected to the electrically conductive pipe; a lead wire placed inside the electrically conductive pipe along a longitudinal direction of the electrically conductive pipe and spaced a prescribed distance away from an inside wall of the electrically conductive pipe, thereby forming a coaxial line together with the electrically conductive pipe; and a wireless tag circuit, electrically connected at one end to the contact and at the other end to the lead wire, for generating a response signal in response to an interrogation signal transmitted from a reader/writer.
摘要:
A wireless frequency tag includes a loop-shaped antenna pattern that is electrically connected to a chip connecting section, and a conducting member that electrically couples a part of the antenna pattern.