摘要:
There are provided a variable inductor with little degradation in quality factor, and an oscillator and a communication system using the variable inductor. An inductance controller comprising a reactance device with a variable device value, such as, for example, a variable capacitor, is connected to a secondary inductor, magnetically coupled to a primary inductor through mutual inductance. The inductance controller is provided with an inductance control terminal for receiving a control signal for controlling capacitance of the variable capacitor. Inductance of the primary inductor is varied by varying the capacitance by the control signal.
摘要:
There are provided a variable inductor with little degradation in quality factor, and an oscillator and a communication system using the variable inductor. An inductance controller comprising a reactance device with a variable device value, such as, for example, a variable capacitor, is connected to a secondary inductor, magnetically coupled to a primary inductor through mutual inductance. The inductance controller is provided with an inductance control terminal for receiving a control signal for controlling capacitance of the variable capacitor. Inductance of the primary inductor is varied by varying the capacitance by the control signal.
摘要:
There are provided a variable inductor with little degradation in quality factor, and an oscillator and a communication system using the variable inductor. An inductance controller comprising a reactance device with a variable device value, such as, for example, a variable capacitor, is connected to a secondary inductor, magnetically coupled to a primary inductor through mutual inductance. The inductance controller is provided with an inductance control terminal for receiving a control signal for controlling capacitance of the variable capacitor. Inductance of the primary inductor is varied by varying the capacitance by the control signal.
摘要:
A frequency synthesizer comprises: a single-tone signal generator which outputs signals of a single frequency; a frequency multiplier which generates one or more intermediate signals having different frequencies based on frequencies of input signals and outputs the same as output signals; a frequency selector; a mixer; and a frequency synthesizer control circuit which includes a frequency synthesizer control terminal, wherein an output of the single-tone signal generator is set as an input of the frequency multiplier, one or more outputs of the frequency multiplier are set as one or more inputs of the frequency selector, an output of the frequency selector and one output of the outputs of the frequency multiplier are set as first and second inputs of the mixer, and an output of the mixer is set as an output of the frequency synthesizer.
摘要:
The present invention provides a semiconductor integrated circuit including an active mixer circuit that is operated at low voltage, low noise, and low power consumption. It includes a transconductance amplifier, a transformer, and a multiplier, connects a transformer between the transconductance amplifier and the multiplier, and separates between the transconductance amplifier and the multiplier with respect to direct current inside the transformer. Further, each of the tranconductance amplifier and the multiplier is configured of transistors that are single-stacked between the supply voltage terminal and ground terminal.
摘要:
An LC resonant circuit of an oscillator includes a parallel circuit of an inductor, a first fine adjustable capacitor and a first capacitor bank, and a series circuit of a second fine adjustable capacitor and a second capacitor bank. A frequency conversion gain of the oscillator is the sum of a frequency conversion gain of the oscillator based upon the first fine adjustable capacitor which decreases according to increase of a capacitance value of the capacitor bank and a frequency conversion gain based upon the second fine adjustable capacitor which increases according to increase of a capacitance value of the second capacitor bank. Accordingly, an LC resonant circuit for an oscillator with reduced fluctuation of a frequency conversion gain, and an oscillator and a data processing equipment using the same are provided.
摘要:
The present invention provides a voltage-controlled oscillator operating from microwave frequencies to millimeter wave frequencies, which is capable of outputting a large power with an output impedance thereof being set up to a predetermined level at low power consumption, and a communication device using the same. The voltage-controlled oscillator includes: a differential alternating current generator including a resonator capable of varying resonant frequency according to an input control voltage, for generating a pair of differential alternating current each of which having the same frequency with the resonant frequency of the resonator yet being 180 degrees out of phase in mutual; a pair of transformers each of which having a primary inductor and a secondary inductor, for conducting the alternating current to the primary inductor; and an impedance-matching circuit connected to the secondary inductor of the transformers, wherein an output signal is outputted from the secondary inductors of the transformers.
摘要:
The object of the invention is to provide a frequency generator which is composed of an oscillator and a frequency doubler and in which difference in amplitude between differential outputs of the frequency doubler can be equalized at low power consumption without adjustment. To achieve the object, the amplitude of differential outputs of the frequency doubler is detected and the delay time of a variable delay circuit is controlled. Owing to this configuration, in case a frequency of the oscillator varies or in case delay time by the delay circuit used in the frequency doubler varies by process variation and others even if the frequency is fixed, the amplitude of the differential outputs of the frequency doubler can be also equalized in the frequency generator.
摘要:
An optical receiver generates a voltage signal having a predetermined swing from a current signal, and feeds the voltage signal to a decision circuit. An optical receiving element receives the input optical signal, converts the optical signal to a current signal, and provides the current signal to a preamplifier, which converts the input current signal into a voltage signal. The voltage signal is input to an amplifier having a limiting function, which linearly amplifies the voltage signal when the swing of the voltage signal is smaller than a predetermined value, and limitedly amplifies the voltage signal when the voltage signal is greater than the predetermined value. An automatic-gain-control amplifier receives the output from the amplifier with the limiting function, and amplifies the input voltage signal to a voltage signal having a constant swing. The decision circuit receives the output of the automatic-gain-control amplifier and decides the binary nature of the voltage, and thus of the input optical signal.
摘要:
An inter-network connection system wherein a local signaling network including gateway offices of at least two signaling networks to be interconnected is configured between the signaling networks to be interconnected, and the inter-network connection is carried out through the local signaling network.