Abstract: In an input signal power dynamic range compressing circuit, an input signal is distributed by a directional coupler to a linear signal transfer path and a compressing signal generating path, and in the compressing signal generating path a compressing signal, which keeps the peak-to-average-power ratio of the input signal below a predetermined value, is generated from the input signal. The compressing signal is combined by a power combiner with the input signal having passed through the linear signal transfer path.

Abstract: A circuit for extending the dynamic range of an electronic circuit is provided. The circuit includes a first adjustable attenuation circuit having an input and an output and a control input. The control input is adapted to receive a control signal that adjusts the relative gain of the attenuation circuit. The circuit also includes at least one additional attenuation circuit coupled in parallel with the first adjustable attenuation circuit. The at least one additional attenuation circuit has a control input that is adapted to receive a control signal that adjusts the relative gain of the at least one additional attenuation circuit. The first and the at least one additional attenuation circuits are selectively controlled to adjust the level of signals in different frequency bands so as to extend the dynamic range of signals to be processed by the electronic circuit.

Abstract: An apparatus and method for tuning a filter (11) with oscillator alignment for applications where the filter tuning signal (19,27) is generated independently of the local oscillator tuning signal and the tuning range is large, for example such as terrestrial and cable TV broadcasting (40 to 860 MHz). The filter being adapted to a filter tuning modulation signal (25) having a first frequency (F1) and a second frequency (F2). Values of the output signal (28) are measured, a first value (S1) at the first frequency, and a second value (S2) at the second frequency, and a comparison signal (26) is generated in comparing the first value and the second value to adjust filter with the tuning control signal in response to the comparison signal, modulation signal and an approximate filter tuning signal to provide a desired signal at the output signal.

Abstract: A method of tuning individual filters in an assembly of filters connected to a manifold, such as a microwave multiplexer, prior to assembly of the multiplexer, is accomplished by energizing a subject filter to be tuned with an electromagnetic signal provided by a network analyzer. The filter is tuned by adjustment of a tuning component, such as a tuning screw within the filter, while the network analyzer presents the transfer function of the filter during the tuning process. To compensate for tuning effects of the other filters and of the manifold, which are manifested upon a connection of the filters to the manifold, the transfer function of the assembly is loaded into a computer of the network analyzer. Thereby, during a tuning of the filter, the presentation of the filter transfer function by the network analyzer includes the tuning effects of the rest of the assembly.

Abstract: A system and method for filter tuning are presented. The system comprises means for adjusting the components of a filter by coarse adjustments such that the filter is set with an initial cutoff frequency of adequate accuracy to satisfy the requirements of the filter application, and means for adjusting the components of the filter by fine adjustments such that the filter is set to maintain the accuracy of the initial cutoff frequency in response to cutoff frequency drift. The method comprises the steps of adjusting the components of a filter by coarse adjustments such that the filter is set with an initial cutoff frequency of adequate accuracy to satisfy the requirements of the filter application, and adjusting the components of the filter by fine adjustments such that the filter is set to maintain the accuracy of the initial cutoff frequency in response to cutoff frequency drift.

Abstract: A high-frequency filter device includes at least one filter to be connected to a high-frequency stage of a wireless apparatus. The filter includes a voltage-controlled variable frequency resonance element which is made of a resonance element and a voltage-controlled variable impedance element electrically connected to the resonance element. The high-frequency filter device includes a control section for controlling a voltage applied to the variable impedance element, and a signal monitoring section for outputting a control signal, with which the voltage is controlled, to the control section based on frequency data as to an oscillating frequency of a local oscillator of the wireless apparatus. The signal monitoring section controls a band frequency of the at least one filter based on the frequency data in such a manner that the band frequency is adaptively changed.

Abstract: Single and multiple ferrite crystal resonator, oscillator, and filter coupling structures are disclosed. In one embodiment, a single ferrite crystal resonator coupling structure is configured as a single pole YIG-tuned-oscillator (YTO) coupling structure. The YTO coupling structure includes a circuit substrate having an upper and a lower side. The circuit substrate includes an aperture extending through the circuit substrate between first and second openings on the upper and lower sides, respectively. The aperture is configured to permit rotation of a ferrite crystal disposable at least partially therein about a plurality of axes whereby a desirable axis of the ferrite crystal is alignable with a magnetic field within the aperture. At least one coupling line through which an electric current can be directed, which extends between a first end and a second end of the first opening of the aperture across at least a portion of the first opening of the aperture.

Abstract: Tuning method for a combiner filter (2) in an antenna (3) near system for base station equipment is disclosed. Transmitted signals related to the combiner filter are compared with each other. A spectral analysis of each of the transmitted signals is performed. The spectral analysis results regarding magnitudes and/or phases of the signals are compared. The combiner filter (2) is tuned based on the analysis in an iteration procedure until the combiner filter is in accordance with predetermined conditions.

Abstract: An apparatus for collecting RF signal measurement data at signal ports of an RF and microwave device-under-test (DUT). The apparatus comprises means for measuring incident and reflected RF signals at the signal ports of the DUT. Synthesizer means for generating RF signals at a fundamental frequency and higher harmonics. Tuner means arranged for loading the DUT under different impedance conditions for the fundamental frequency and higher harmonics, and means for feeding the RF signals of the synthesizer means to the signal ports of the DUT. The apparatus may form part of a Non-linear Network Measurement System (NNMS).

Abstract: A circuit for providing a control voltage for tunable dielectric devices, the circuit comprising an input for receiving a voltage command signal, a charging circuit for establishing a desired voltage level on a first capacitor in response to the voltage command signal, and a switch for switching voltage on the first capacitor to a tunable dielectric device to control a dielectric constant of tunable dielectric material in the tunable dielectric device. A second capacitor, second charging circuit, and second switch can be used to provide voltage to the tunable dielectric device during charging or discharging of the first capacitor. The method for providing a control voltage for tunable dielectric devices performed by these circuits is also included.

Abstract: The invention relates to a tunable on-chip capacity circuit for a semiconductor chip (10) mounted on a substrate (30) and including a plurality of power supply decoupling capacitors (20-23) which can be selectively activated or deactivated by being switched on or off the power supply system. An on-chip detecting circuit (32) determines a circuit specific load/unload frequency of the on-chip power supply network, and on-chip control means (28, 33) responsive to signals of the detecting circuit increases or decreases the total of the on-chip capacity (CSD) by selectively activating or deactivating power supply decoupling capacitors (20-23). Off-chip path impedances (LMC, RMC), an off-chip capacity (CM) and the total on-chip capacity (CC), including the plurality of power supply decoupling capacitors (20-23) and parasitic on-chip capacities (CP), form a resonance loop (40) which is tunable by changing the total capacity (CSD) of the on-chip power supply decoupling capacitors.

Abstract: A method of tuning a microwave or RF circuit is given which comprises the steps of taking a microwave or RF circuit (20) located in a casing (57), said casing comprising a housing portion (32) and a window portion (50), said window portion (50) being substantially conducting at microwave/RF frequencies, and comprising at least one area that is substantially transparent at optical frequencies and, directing a laser beam (66) onto said microwave or RF circuit through said window portion (50) so as to alter the material properties of selected areas of said microwave or RF circuit (20). This permits microwave and RF circuits, including microwave filters, to be tuned without the need for tuning screws.

Abstract: A tunable resonant system includes an electric element, and a core having a controllable parameter that determines the resonant frequency of the system. In order to tune the resonant system to a desired frequency, a low power, narrowband signal is applied at a selected frequency to the electric element. The reflected or transmitted power is measured and the value of the controllable parameter adjusted to vary the resonant frequency of the system in a closed loop until the reflected power is at a minimum.

Abstract: A tunable resonator is provided. The resonator includes a housing having a cavity. A resonator body is disposed adjacent to a first surface within the cavity. A gap is formed between the resonator body and the first surface. The resonator is tuned by controlling the size of the gap.

Abstract: A circuit for extending the dynamic range of an electronic circuit is provided. The circuit includes a first adjustable attenuation circuit having an input and an output and a control input. The control input is adapted to receive a control signal that adjusts the relative gain of the attenuation circuit. The circuit also includes at least one additional attenuation circuit coupled in parallel with the first adjustable attenuation circuit. The at least one additional attenuation circuit has a control input that is adapted to receive a control signal that adjusts the relative gain of the at least one additional attenuation circuit. The first and the at least one additional attenuation circuits are selectively controlled to adjust the level of signals in different frequency bands so as to extend the dynamic range of signals to be processed by the electronic circuit.

Abstract: A method which is capable of easily obtaining specified filter characteristics in a short time, even in the case of a dielectric filter having complicated relationships between changes in the filter characteristics and the amount that a specified part of a dielectric member or a dielectric film is trimmed. In the dielectric filter, data is obtained in advance showing the relationships between the amounts that specified parts of a conductive film or a dielectric member are trimmed, and the corresponding changes in the values of a center frequency and a coupling coefficient between resonators. Further, adjustment values are obtained from the initial characteristics of the dielectric filter to be adjusted, and then, the targeted amounts of trimming are obtained from the adjustment values, targeted adjustment values, and the aforementioned data concerned so as to perform trimming.

Abstract: The invention relates to trimming of analogue filters (201) in integrated circuits by means of an automatic adjusting circuit. A local oscillator (202) in the automatic adjusting circuit provides a periodic reference signal (R) to an adjustable phase shifter (203), which on basis thereof, produces a periodic phase shifted signal (R*). A phase detector (204) receives both the periodic reference signal (R) and the phase shifted period signal (R*) and produces a test signal (T) in response to a phase difference between the periodic reference signal (R) and the periodic phase shifted signal (R8). A lowpass filter (205) receives the test signal (T) and generates a level signal (TDC) relative a reference level, e.g. representing a zero voltage. A digital signal processor (207) produces a primary control signal (CS), having a serial format, on basis of the observation signal (M). A serial-to-parallel converter (208) converts the primary control signal (CS) into a control signal (CP) having a parallel signal format.

Abstract: An electronic apparatus for automatically detecting the length of network transmission lines. The electronic apparatus essentially comprises a detection device, an analog/digital (A/D) converter, a microprocessor, a frequency compensator and a transmission network line, such as an RJ-45 network transmission line. The electronic apparatus utilizes the detection device to detect a frequency response of the reference signal for generating detection signals and converts the detection signals into digital signal. Thereafter, the microprocessor outputs a control signal so that the frequency compensator, comprising resistors and capacitors, makes up for the video frequency according to the control signal. As a result, the optimum video frequency is generated to display a clear image on a monitor for the benefit of the operation.

Abstract: A point-to-point microwave radio link that operates in a Frequency Division Duplex (FDD) mode using direct digital modulation with a Continuous Phase Shift Keyed (PSK) scheme. The transmit signal is generated by a circuit that uses a Voltage-Control Oscillator (VCO) operating in a microwave radio band to obtain the modulated signal. The VCO output is fed to a phase modulator to obtain the modulated signal. The output of the VCO is then frequency multiplied by the predetermined factor to produce the modulated microwave output signal at the desired band.

Abstract: A circuit for providing a control voltage for tunable dielectric devices, the circuit comprising an input for receiving a voltage command signal, a charging circuit for establishing a desired voltage level on a first capacitor in response to the voltage command signal, and a switch for switching voltage on the first capacitor to a tunable dielectric device to control a dielectric constant of tunable dielectric material in the tunable dielectric device. A second capacitor, second charging circuit, and second switch can be used to provide voltage to the tunable dielectric device during charging or discharging of the first capacitor. The method for providing a control voltage for tunable dielectric devices performed by these circuits is also included.

Abstract: A high-frequency filter device including at least one filter to be connected to a high-frequency stage of a wireless apparatus, in which the filter includes a voltage-controlled variable frequency resonance element which comprises a resonance element and a voltage-controlled variable impedance element electrically connected to the resonance element. In the high-frequency filter device, which is connected to a receiver-side antenna, a signal monitoring section monitors unnecessary interfering signals of a received signal of a receiver of the wireless apparatus and generates a control signal for reception by an adaptive control algorithm, and a control section controls a band elimination filter by a control voltage signal based on the control signal so that an elimination band of the band elimination filter of the receiving filter maximizes a ratio of a desired received signal to interfering waves.

Abstract: An antenna circuit is described which makes it possible to suppress intermodulation products. This antenna circuit includes an antenna connection device to which at least one first antenna can be connected, and the antenna connection device can be connected to an output of the antenna circuit over at least two signal paths. An antenna signal can be transmitted over each signal path. Transmission of a second antenna signal over a second signal path is attenuated by a predetermined attenuation value in comparison with a transmission of a first antenna signal over a first signal path. An analyzer unit is provided to determine the level of a weighting signal which is derived from an antenna signal transmitted to the output of the antenna circuit. An operating device is provided to connect only the first signal path to the output of the antenna circuit when the detected level is below a first predetermined level.

Abstract: A method and an apparatus for exactly and automatically adjusting the characteristics of a dielectric filter in a short time period. The characteristic parameters of a dielectric filter are measured, electric parameters of a designed equivalent circuit of the filter are calculated with the use of characteristic parameters, characteristic adjusting portions of the dielectric filter are adjusted, while at the same time, adjustment functions indicating the variation amounts of electric parameters with respect to adjusting amounts are calculated with the use of the electric parameters and the adjusting amounts which have been changed by the above adjustment. Then, in accordance with simultaneous equations involving adjustment functions, an adjusting amount is calculated with the use of a difference between a present electric parameter and a desired electric parameter, thereby effecting an adjustment which is for example 50%.

Abstract: A tunable resonant system includes an electric element, and a core having a controllable parameter that determines the resonant frequency of the system. In order to tune the resonant system to a desired frequency, a low power, narrowband signal is applied at a selected frequency to the electric element. The reflected or transmitted power is measured and the value of the controllable parameter adjusted to vary the resonant frequency of the system in a closed loop until the reflected power is at a minimum.

Abstract: A system and method for a filter tuner is presented. The system comprises a sequential logic, a register, a comparator, a first and second counter, a synchronizing logic, a first and second oscillator, a control logic, and a first and second combinational logic. The method comprises the steps of executing a calibration cycle of a filter tuner, executing a measurement cycle of the filter tuner, and tuning a filter with the filter tuner dependent on a determined cutoff frequency variation.

Abstract: The invention relates to a bandpass filter that follows the frequency of an input signal especially for reducing the noise on the receive band of mobile communications devices. More specifically the invention relates to a method and arrangement for tuning a resonator (100), where an input signal feeds the resonator in such a manner that the resonator oscillates at, the frequency of the input signal, and where the center frequency of the pass band of the resonator is set substantially to the frequency of the input, signal. In accordance with the invention, there is generated (200) a difference signal (Vc, Ve) proportional to the phase difference (&Dgr;&phgr;) between the input signal voltage (Vi) and resonator voltage (Vo) and the resonance frequency of the resonator is changed using the difference signal in such a manner that said phase difference becomes smaller.

Abstract: A tuning method for filters having multiple coupled resonators isolates the characteristics of each resonator, enabling a specified filter response to be achieved by adjusting the resonators according to response criteria. A target frequency response is defined for the filter and a target time domain response is computed based on the target frequency response. From the time domain response, a gating function is generated for each of the resonators. A stimulus signal is provided to the filter and the response to the stimulus signal is measured. The gating functions are then applied to isolate the characteristics of each resonator. Each resonator is adjusted according to response criteria chosen to achieve a specified filter response when the response criteria are satisfied.

Abstract: A primary winding of a first insulating transformer for balance-to-unbalance transformation is connected between the central electrode and the outer electrode of an input terminal, and windings of a noise eliminating transformer are provided within balanced lines on the side of a secondary winding of the first insulating transformer. A primary winding of a second insulating transformer for balance-to-unbalance transformation is connected between the central electrode and the outer electrode of an output terminal, and balanced lines on the side of the secondary winding of the second insulating transformer is connected to the noise eliminating transformer. One end of each of the primary windings, which is grounded to the ground line, is connected to the middle point of the secondary winding of each insulating transformer.

Abstract: A tuning method for filters having multiple coupled resonators isolates the characteristics of each resonator, enabling a specified filter response to be achieved by adjusting the resonators according to response criteria. A target frequency response is defined for the filter and a target time domain response is computed based on the target frequency response. From the time domain response, a gating function is generated for each of the resonators. A stimulus signal is provided to the filter and the response to the stimulus signal is measured. The gating functions are then applied to isolate the characteristics of each resonator. Each resonator is adjusted according to response criteria chosen to achieve a specified filter response when the response criteria are satisfied.

Abstract: A tuning method for filters having multiple coupled resonators isolates the characteristics of each resonator, enabling a specified filter response to be achieved by adjusting the resonators according to response criteria. A target frequency response is defined for the filter and a target time domain response is computed based on the target frequency response. From the time domain response, a gating function is generated for each of the resonators. A stimulus signal is provided to the filter and the response to the stimulus signal is measured. The gating functions are then applied to isolate the characteristics of each resonator. Each resonator is adjusted according to response criteria chosen to achieve a specified filter response when the response criteria are satisfied.

Abstract: A method and system for tuning a tunable bandpass filter includes a bandpass filter having a passband which is dependant on the value of a tuning signal. A data signal having a dominant frequency component is applied to the filter and the power of the signal passed by the filter is determined. The tuning signal is adjusted until the passed power is maximized, indicating that the filter is tuned to the dominant frequency. The tuning signal can then be applied to other tunable circuits, including an oscillator having an output used as a clock signal to extract data from the data signal applied to the filter.

Abstract: A tunable electronic filter circuit is provided including an input terminal and an output terminal connected to the input terminal with a node therebetween. An inductor, a variable capacitor, and a variable resistor are connected between the node and ground. Coupled to the variable capacitor and the variable resistor is a feedback control circuit. The feedback control circuit is operable to tune the variable capacitor in order to set a predetermined frequency, or center frequency, of the electronic filter circuit. The feedback control circuit is further operable to tune the variable resistor in order to calibrate a quality factor of the electronic filter circuit. In use when an input signal is applied to the input terminal, the electronic filter circuit passes an output signal to the output terminal. Such output signal includes components of the input signal within a predetermined frequency bandwidth set by the predetermined frequency and filters out other components of the input signal.

Abstract: A method for characterizing a frequency response of a tunable filter (11) includes the steps of adjusting a tuning means (12) to a first predetermined position; measuring the resonance frequency of the filter (10); temporary storing the measured resonance frequency and the position; and repeating these steps for a number of different predetermined positions of the tuning means. A mathematical function representing tuning means position as a function of resonance frequency is then determined, whereby several advantages are achieved. Little memory is required and the function provides for rapid and accurate tuning of the filter.

Abstract: A temperature compensated variable attenuator comprising a variable attenuator having at least one diode with temperature variations across the at least one diode producing a temperature offset signal. A bias source coupled to the variable attenuator supplies a biasing signal to the at least one diode through a temperature compensation source. The temperature compensation source is coupled between the bias source and the variable attenuator with the temperature compensation source comprising at least one diode capable of producing a temperature offset signal approximately equivalent to the temperature offset signal produced by the first at least one diode. The approximate temperature offset signal subtracted from the biasing signal produces a temperature compensated bias signal that is supplied to the variable attenuator.

Abstract: Tuning method for a combiner filter (2) in an antenna (3) near system for base station equipment is disclosed. Transmitted signals related to the combiner filter are compared with each other. A spectral analysis of each of the transmitted signals is performed. The spectral analysis results regarding magnitudes and/or phases of the signals are compared. The combiner filter (2) is tuned based on the analysis in an iteration procedure until the combiner filter is in accordance with predetermined conditions.