Abstract:
A power amplifier includes amplifier elements to amplify input signals of different frequencies. The amplifier also includes a power supply circuit that includes a common power supply path including an end connected to a power supply input terminal connected to a DC power supply. The amplifier further includes individual power supply paths each including an end connected to the other end of the common power supply path, and the other end connected to the main electrode of a corresponding one of the amplifier elements. The individual power supply paths have different impedances.
Abstract:
A filter circuit includes a plurality of resonators connected in parallel and each having loaded Q deviation equal to allowable deviation of a group delay, a divider to divide an input signal to the resonators, a combiner to combine output signals of the resonators, and an opposite phase unit for making signals passing two resonators of the resonators an approximately opposite phase in an output of the combiner, the two resonators having resonance frequencies adjacent to each other, respectively.
Abstract:
In a radio apparatus, the band of a loop filter of a synthesizer in a blank channel searching state is narrower than the band in a communicating state. In addition, a radio wave environment is measured. A characteristic necessary for the radio apparatus is determined corresponding to the measured radio wave environment. The power is controlled corresponding to the performance of the radio apparatus. Thus, the power consumption is decreased. In addition, the efficiency of the output power is improved. In the radio apparatus, the current consumption of a power amplifier PA is measured. A matching circuit (LNA or MIX) of the antenna is adjusted with the measured result so as to decrease an antenna loss. In the radio apparatus, a DC offset is removed from the transmitted power and the reflected wave. When the DC offset is removed using an AC coupling capacitor, the deterioration of the frequency characteristic of the receiving portion is compensated with a capacitor in a digital signal process. In the radio apparatus, a transmission power detecting portion is structured as an IC chip. The transmission power detecting portion detects the transmission power corresponding to leakage currents in the power supply of the IC chip and the ground. Thus, when the power is detected, a power loss is suppressed. Consequently, the power consumption of the radio apparatus can be decreased.
Abstract:
A first electrically conductive layer whose thickness is equal to or smaller than the skin depth of the radio wave used for communication, a dielectric layer whose permittivity is changed by application of electric field, and a second electrically conductive layer whose thickness is equal to or smaller than the skin depth of the radio wave used for communication are sequentially stacked near a resonance element which is formed on the front surface of a dielectric substrate having a ground layer formed on the rear surface thereof. The effective permittivity of the dielectric layer is changed in a wide range by changing a voltage applied between the first and second electrically conductive layers to change the electric field applied to the dielectric layer. As a result, the impedance of the resonance element is changed, and when a plurality of resonance elements are arranged closely to each other to construct a filter, the coupling degree between the resonance elements is changed. Therefore, characteristics such as the resonance frequency of the resonator and the pass-band frequency of the filter are controlled by controlling a voltage to be applied.
Abstract:
According to one embodiment, there is provided a reporter gene construct. The reporter gene construct comprises a transcriptional regulatory sequence and a reporter gene that is functionally bound to downstream of the transcriptional regulatory sequence. The reporter gene construct is activated dependently of environment and the reporter gene codes for a protein producible of producing a free radical by the activation of the transcriptional regulatory sequence.
Abstract:
One embodiment of a high-frequency filter includes a band-rejection filter including a plurality of reflection-type resonance elements and a filter circuit element provided between the reflection-type resonance elements, wherein an electrical length between the reflection-type resonance elements between which the filter circuit element is provided is an odd multiple of 90 degrees in a rejection band of the band-rejection filter.
Abstract:
According to one embodiment, there is provided a reporter gene construct. The reporter gene construct comprises a transcriptional regulatory sequence and a reporter gene that is functionally bound to downstream of the transcriptional regulatory sequence. The reporter gene construct is activated dependently of environment and the reporter gene codes for a protein producible of producing a free radical by the
Abstract:
In resonant elements 102 to 105 constituting a resonant circuit, an uncontrolled cross coupling which exists between two resonant elements is controlled by using a coupling element 106 which is newly arranged between the resonant elements, whereby it is possible to create a state where two resonant elements are not coupled with each other or a state where the amount of the coupling is reduced, which states are difficult to be realized on a plane. As a result, it is possible to improve characteristics of a planar filter.
Abstract:
The present invention provides a resonator and a filter that reduce the resonator radiation loss so as to achieve a high Q value that is inherent to a low-loss material while maintaining high power handling capability. In this manner, both high power handling capability and a high Q value can be achieved at the same time. The resonator is a microstripline structure and includes a line structure formed with resonance lines in which current standing waves are generated in a resonant state in a line, and currents in each two adjacent lines flow in the opposite directions from each other, and a connection line that connects the resonance lines at the portions having in-phase voltages among the nodes of the current standing waves of the resonance lines in the resonant state. The filter includes resonators of the same type as the above resonator.
Abstract:
The present invention provides a filter circuit that can achieve both sharp bandpass characteristics and high power handling capability. The filter circuit includes: an input terminal that has a signal input; a four-port device that divides input signals; a band stop filter that has the center frequency of the input signals within the stopband, and causes the out-of-stopband signals among the input signals to pass; two bandstop resonators circuits that cause the signals passing through the band stop filters to pass, and reflect the signals; open ends that are connected in parallel to the two bandstop resonators circuits; and an output terminal that outputs the signals reflected by the band stop filters and the bandstop resonators circuits and combined at the four-port device.