Voltage-controlled oscillator (VCO) having a voltage derived from its output to tune its center frequency
First Claim
1. A tunable voltage-controlled oscillatory (VCO) circuit which produces an electric oscillating signal during operation, and which comprises a means (5) for tuning a center frequency of the tunable VCO circuit based on an electric signal, characterized in that it comprises means (14, 15, RE) for continuously generating, during the operation of said tunable VCO circuit, said electric signal internally within said tunable VCO circuit, on the basis of said electric oscillating signal.
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Accused Products
Abstract
The invention is related to an electrically tunable voltage-controlled oscillatory circuit, wherein the negative bias voltage (-Vcf) of a capacitance diode (5) needed for tuning the center frequency of the oscillatory circuit is generated on the basis of an electric oscillating signal (RFout) produced by the oscillatory circuit itself. Said oscillating signal is used for generating a negative voltage with a clamp/voltage multiplier type circuit (15) and it is adjusted to a desired value with an adjustment circuit (14), in which the values of the components (R2) can be permanently adjusted suitable in the tuning stage. Alternatively, the adjustment circuit (14) may include an active component (Q1) which can have an effect on the value of the negative bias voltage (-Vcf) during the use of the oscillatory circuit.
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Citations
22 Claims
- 1. A tunable voltage-controlled oscillatory (VCO) circuit which produces an electric oscillating signal during operation, and which comprises a means (5) for tuning a center frequency of the tunable VCO circuit based on an electric signal, characterized in that it comprises means (14, 15, RE) for continuously generating, during the operation of said tunable VCO circuit, said electric signal internally within said tunable VCO circuit, on the basis of said electric oscillating signal.
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5. A tunable voltage-controlled oscillatory (VCO) circuit which produces an electric oscillating signal, and which comprises a means (5) for tuning its center frequency using an electric signal, characterized in that it comprises means (14, 15, RE) for generating said electric signal on the basis of said electric oscillating signal, said tuning means comprising a capacitance diode (5), wherein said generating means (14, 15, RE) is for changing the voltage across said capacitance diode on the basis of the operation of said tunable voltage-controlled oscillatory circuit in order to tune said center frequency, said generating means comprising a means (15) for generating a first voltage (-Vcf'"'"') on the basis of said electric oscillating signal and a means (14, RE) for directing said first voltage (-Vcf'"'"') to said capacitance diode (5) for biasing, said first voltage generating means comprising a clamp/voltage multiplier circuit (15;
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C1 to C4) for generating said first voltage (-Vcf'"'"') on the basis of said electric oscillating signal, and wherein said directing means includes a voltage level adjustment circuit (14;
R1, R2, C5) for adjusting the value of said first voltage (-Vcf'"'"').
- D1 to D4;
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9. A tunable voltage-controlled oscillatory (VCO) circuit which produces an electric oscillating signal, and which comprises a means (5) for tuning its center frequency using an electric signal, characterized in that it comprises means (14, 15, RE) for generating said electric signal on the basis of said electric oscillating signal, said generating means comprising a second part (Q1) the electric characteristics of which can be repeatedly adjusted in connection with the use of said tunable voltage-controlled oscillatory circuit for the purpose of tuning the center frequency of said tunable voltage-controlled oscillatory circuit, wherein said second part includes a field-effect transistor (Q1), and wherein the adjustment of said electrical characteristics changes a gate voltage of said second part.
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10. A method for tuning a center frequency of a voltage-controlled oscillator (VCO) device, the VCO device including an input port and a capacitance diode having a first terminal coupled to the input port, the method comprising the steps of:
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applying a control voltage to the input port of the VCO device to cause the VCO device to output a signal of a particular frequency; and tuning the center frequency of the VCO device by continuously generating, during the operation of the VCO device, a tuning signal internally within the VCO device, on the basis of the signal output by the VCO device, and providing the tuning signal to a second terminal of the capacitance diode for biasing the capacitance diode. - View Dependent Claims (11, 12)
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13. A tunable, two-port voltage-controlled oscillator (VCO) device, comprising:
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an input port; an output port; resonating means coupled between said input port and said output port; a first amplifier interposed between an output of said resonating means and said output port; a first, inner, negative feedback loop portion, said first negative feedback loop portion having a first end coupled to an input of said first amplifier and a second end coupled to an output of said first amplifier; and a second, outer, negative feedback loop portion, said second negative feedback loop portion having a first end coupled to an input of said resonating means and a second end coupled to said output port; wherein, during the operation of said VCO device, said VCO device provides an output signal in response to a control voltage being applied to said input port, said output signal having a frequency that is a function of said control voltage, and wherein, during the operation of said VCO device, said second negative feedback loop continuously generates, internally within said VCO device, a tuning signal based on said output signal, said tuning signal for controlling the tuning of a center frequency of said VCO device. - View Dependent Claims (14, 15, 16, 17, 18, 19, 20, 21, 22)
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Specification