Abstract:
Die Erfindung betrifft eine Vorrichtung mit einstellbarem Kapazitätswert zum Abstimmen eines ersten schwingfähigen Systems (10), das zur Kopplung mit einem zweiten schwingfähigen System (20) mit nicht bekanntem, schwachen Kopplungsfaktor vorgesehen ist. Die Vorrichtung umfasst einen ersten Kondensator (C var ), dessen Kapazität abhängig von einer Spannung ist, und eine Gleichspannungsquelle (DC var ), deren an ihren Klemmen anliegende Spannung steuerbar ist, wobei die Serienschaltung aus der Gleichspannungsquelle (DC var ) und einem Entkoppelelement (L entk ) parallel zu den Klemmen des Kondensators geschaltet ist, um den ersten Kondensator (C var ) mit einer variablen Vorspannung zu beaufschlagen. Die an den Klemmen der Gleichspannungsquelle (DC var ) anliegende Spannung wird in Abhängigkeit einer Arbeitsfrequenz des ersten schwingfähigen Systems (10) eingestellt.
Abstract:
Exemplary embodiments are directed to a programmable varactor device. A varactor device may include an input device configured to receive a tuning voltage and generate a bias voltage at least partially dependent on the tuning voltage. The varactor device may also include a varactor pair coupled to the input device and having a first variable capacitor and a second variable capacitor, wherein each of the first variable capacitor and a second variable capacitor are configured for operable coupling to each of the bias voltage and the tuning voltage.
Abstract:
Exemplary embodiments are directed to a programmable varactor device. A varactor device may include an input device configured to receive a tuning voltage and generate a bias voltage at least partially dependent on the tuning voltage. The varactor device may also include a varactor pair coupled to the input device and having a first variable capacitor and a second variable capacitor, wherein each of the first variable capacitor and a second variable capacitor are configured for operable coupling to each of the bias voltage and the tuning voltage.
Abstract:
Methods and means related to an electronic circuit having an inductor and a memcapacitor are provided. Circuitry is formed upon a substrate such that an inductor and non-volatile memory capacitor are formed. Additional circuitry can be optionally formed on the substrate as well. The capacitive value of the memcapacitor is adjustable within a range by way of an applied programming voltage. The capacitive value of the memcapacitor is maintained until reprogrammed at some later time. Oscillators, phase-locked loops and other circuits can be configured using embodiments of the present teachings.
Abstract:
A signal having a substantially uniform spectral distribution, e.g., a flat noise signal such as a signal ground, is provided at the input of a bandpass filter such as an IF filter of a receiver circuit, to thereby produce an output signal at the output of the bandpass filter. The output signal is processed in a limiter to produce a limited signal. An average frequency of the limited signal is determined, and the bandpass filter is adjusted based on the determined average frequency. According to one embodiment of the present invention, the bandpass filter comprises a Gm-C filter having a transconductance, and the filter is adjusted by adjusting the transconductance of the Gm-C filter based on the determined average frequency. According to another aspect of the present invention, a desired center frequency for the bandpass filter is identified. A resolution and a desired confidence interval are also identified. The number of samples of the limited signal needed to achieve the identified desired resolution and confidence interval is determined based on the identified desired center frequency. An average frequency is determined by sampling the limited signal to obtain a plurality of samples, the number of the plurality of samples being at least as great as the determined number of samples of the limited signal to achieve the identified desired resolution and confidence level, and determining the average frequency from the plurality of samples. The bandpass filter is adjusted based on the determined average frequency to achieve a center frequency for the bandpass filter that is within a predetermined range with respect to the desired center frequency. Related apparatus are also discussed.