94results about "Continuous tuning" patented technology

A phase-locked loop frequency synthesizer has a charge pump, phase-locked loop filter, voltage-controlled oscillator, and a bandwidth calibration circuit. The bandwidth calibration circuit measures the gain of the voltage-controlled oscillator and uses the measured voltage-controlled oscillator gain to adjust the charge pump level. The charge pump level is adjusted so that a product of the voltage-controlled oscillator gain and the measured charge pump level results in a constant phase-locked loop bandwidth.

A method for assigning a single frequency sub-channel to a plurality of MSs (Mobile Stations) in an OFDM (Orthogonal Frequency Division Multiplexing) system utilizing SDM (Spatial Division Multiplexing) with multiple transmit / receive antennas. In the method, a BS (Base Station) can effectively assign a pilot channel to estimate a downlink channel. The BS divides the single frequency sub-channel into a plurality of spatial channels, and sequentially assigns the plurality of spatial channels to the MSs having the maximum communication capacity, thereby transmitting signals of the MSs through the single frequency sub-channel.

A phase-locked loop frequency synthesizer has a charge pump, phase-locked loop filter, voltage-controlled oscillator, and a bandwidth calibration circuit. The bandwidth calibration circuit measures the gain of the voltage-controlled oscillator and uses the measured voltage-controlled oscillator gain to adjust the charge pump level. The charge pump level is adjusted so that a product of the voltage-controlled oscillator gain and the measured charge pump level results in a constant phase-locked loop bandwidth.

A filter circuit arrangement for filtering of a radio-frequency signal has a first tunable filter and a phase regulation loop in order to hold the first tunable filter to a transmission phase constant relative to the frequency of the radio-frequency signal. The filter circuit arrangement has a second tunable filter arranged parallel to the first tunable filter in the phase regulation loop. The first tunable filter and the second tunable filter exhibit different attenuation characteristics and are fashioned and connected within the phase regulation loop so that: a capture range of the filter circuit arrangement, in which a tuning of the phase regulation loop to a radio-frequency signal to be filtered is possible is dominated by the attenuation characteristic of the second tunable filter, and so that the transmission behavior of the filter circuit arrangement in operation is dominated by the attenuation characteristic of the first tunable filter, given a tuned phase regulation loop. A circuit arrangement for generation of a local oscillator signal has an oscillation generator and a filter circuit arrangement as described above arranged downstream of the oscillation generator.

Disclosed is a display apparatus including a front cover, a rear cover coupled the front cover and forming an accommodating space, a display panel disposed inside the accommodating space, a main PCB having a signal processor and transmitting a video signal to the display panel, and a PCB supporting member supporting the main PCB. The display apparatus includes a TV tuner unit having a TV tuner receiving the TV video signal, a casing accommodating the TV tuner, and a connector electrically connected with the TV tuner, a tuner unit accommodating part accommodating the TV tuner unit, and a connection port provided at the tuner unit accommodating part for transmitting the TV video signal from the TV tuner unit to the signal processor.

In a tuner unit, a metal shielding plate standing upright on a circuit board is provided between circuit blocks formed on the circuit board so as to electrically shield the circuit blocks from each other. A metal bridge that connects the shielding plate and a frame is provided between some circuit blocks and at a distance from the circuit board so that an electrical component can be mounted on a portion of the circuit board opposing the bridge. This makes it possible to reduce the mounting space for the electrical component and to achieve a small tuner unit.

There is provided a resonance circuit using piezoelectric vibrator such as a quartz resonator, a coil, a capacitor, or an element equivalent to them in combination. When two resonance circuits having different resonance frequencies are combined, it is possible to configure an oscillation circuit and a filter capable of freely adjusting the frequency characteristic by utilizing the phenomenon that by changing the excitation current or voltage of the respective resonance circuits independently from each other, antiresonance frequency of the entire composite resonance circuit can be changed.

A circuit and method for adjusting the operating characteristics of a tuner in accordance with information derived from the signals being processed by the tuner. Depending upon signal type and / or signal strength, the power levels of certain components are adjusted and / or certain components are added to (or subtracted from) the tuner.

A communication module is provided in which its characteristic of separation between its first and second tuner units is improved. The module is equipped with circuit board (21) having a first main surface, and a second main surface opposite to the first main surface; a first amplifier arranged on the first main surface, for amplifying a first signal; a first mixer arranged on the first main surface, for converting a signal supplied from the first amplifier to an intermediate-frequency signal; and a second amplifier for amplifying a second signal; and a mixer for converting a signal supplied from the second amplifier to an intermediate-frequency signal, both arranged on the second main surface of circuit board (21).

In a data processing method of converting (n×m−1)-bit data to multi-level data of m symbols of n bits per symbol, n and m being integers satisfying n≧2 and m≧2, respectively, the m symbols each comprising n-bit data are arranged in m columns in an n×m matrix, with a value of each of the m symbols being set to an even or odd number, by creating the m symbols each including (n−1)-bit data of the (n×m−1)-bit data, arranging the m symbols in the m columns so that the {(n−1)×m}-bit data is arranged in upper-side {(n−1)×m} bits of the n×m matrix, and converting the remaining (m−1)-bit data of the (n×m−1)-bit data to m-bit data so that the m-bit data is arranged in a row in lower-side m bits of the n×m matrix.

A system includes a filter and a tuner formed on an integrated circuit. The filter receives an input signal comprising a first number of channels and communicates an intermediate output signal comprising a second number of channels less than the first number of channels. The tuner is coupled to the filter and receives the intermediate output signal and communicates an output signal comprising a third number of channels less than the second number of channels.

A three-phase voltage-fed AC / DC converter includes a conversion circuit which converts power from a DC voltage source to three-phase AC power. The converter further includes a UM conversion circuit which carries out dq conversion of the three-phase output voltage, a superior voltage control circuit which outputs a voltage reference vector based on a superior reference vector and an output voltage vector obtained by the UM conversion circuit, an inferior voltage control circuit which outputs a PWM reference based on the voltage reference vector and the output voltage vector, and a frequency control circuit which synchronizes a value generated based on a q-axis component from the UM conversion circuit with a rotation angle of a conversion matrix in the UM conversion circuit.

In a radio-controlled timepiece, a tuning unit outputs a signal corresponding to a radio signal. An amplifier unit amplifies a signal output from the tuning unit. A receiving unit that extracts the time code from the amplified signal has a filter unit that selectively allows one of frequency signals to pass therethrough. A time-correcting unit acquires current time information from the extracted time code to correct a current time clocked by a clock unit. A control unit detects a voltage level of a signal output from the amplifier unit at two or more points while changing a capacitance value of a variable-capacitance unit of the tuning unit, uses, as a tuning point, a point meeting a given requirement among the points where the voltage level has been detected, and sets the capacitance value of the variable-capacitance unit at the tuning point as a capacitance value to receive the time code when it is judged that a time code has been output from the receiving unit at the tuning point. When it is judged that no time code is output from the receiving unit at the tuning point, the control unit controls the filter unit so as to change the frequency that the filter unit allows a signal to pass therethrough.

There are provided a single package television tuning apparatus and a television receiver including the apparatus. The apparatus includes: a printed circuit board; a switching part installed on the printed circuit board and selecting one of a first radio frequency signal and a second radio frequency signal inputted; a tuner part installed on the printed circuit board and down-converting one of the first radio frequency signal and the second radio frequency signal, the one selected by the switching part; first and second input connectors receiving the first radio frequency signal and the second radio frequency signal; and a chassis supporting the first and second input connectors, covering the printed circuit board, the switching part, and the tuner part, and electrically connected to grounds of the switching part and the tuner part.

A wideband Voltage Controlled Oscillator (VCO) uses a resonant circuit tunable over a wide range of resonant frequencies. The resonant circuit includes voltage variable elements such that the resonant frequency, and thus the frequency of oscillation, may be electronically tuned. The voltage variable elements are arranged such that multiple control voltages determine the resonant frequency. A first control voltage is applied to a first set of tuning elements and operates as a coarse control of the resonant frequency. A second control voltage is applied to a second set of tuning elements and operates as a fine control of the resonant frequency. Using multiple control voltages on multiple elements allows for a wideband VCO while maintaining a low VCO gain.

A tuner module is characterized by: a chassis formed with lateral surfaces wrapping four corners to open both sides; an upper cover covering one opened side of the chassis to be provided with an elastic fixation end that is fixed at the lateral surface; and a lower cover applying pressure to an external surface of the elastic fixation end to cover the other opened side of the chassis whereby another elastic hitching end that is fixed at the lateral surface is provided.

An energy saving device that is adapted to be connected to a power outlet and further connected to at least one electrical device, said electrical devices drawing power through the energy saving device, the energy saving device including testing means adapted to perform at least one installation verification test and communication means adapted to communicate a validation signal to a monitoring entity when a result of the installation verification test indicates that a correct installation has occurred.

A design structure for an impedance matcher that automatically matches impedance between a driver and a receiver. The design structure for an impedance matcher includes a phase-locked loop (PLL) circuit that locks onto a data signal provided by the driver. The impedance matcher also includes tunable impedance matching circuitry responsive to one or more voltage-controlled oscillator control signals within the PLL circuit so as to generate an output signal that is impedance matched with the receiver.

A method and apparatus for varactor bank switching for a voltage controlled oscillator is disclosed. Varactor bank switching involves generating a negative bias voltage signal as a control signal for a varactor bank switch in an off-state, the varactor bank switch comprising a pass-gate circuit including switching transistors. Generating the negative bias voltage signal includes employing an active rectifier circuit running at the speed of an oscillation signal, the negative bias voltage signal maintaining the gate-source voltage of the pass-gate circuit below a threshold voltage to prevent said switching transistors from becoming conductive in an off-state.

A circuit is proposed by means of which a ceramic component having two electrodes can be provided with a uniform, but periodically alternating BIAS voltage. The component has properties dependent on the level of the BIAS voltage and, for the purpose of an increased service life, is connected to a generator for generating a BIAS voltage and to means for periodically reversing the polarity of the BIAS voltage present at the electrodes. In a method for operating the component having variable properties, a uniform BIAS voltage, the polarity of which is periodically reversed, however, is applied to the electrodes, and the service life of the component is thus increased.

A new slide-screw impedance tuner structure uses multi-segment, disc-shaped, rotating metallic probes. This ensures probes covering multiple frequency bands to be served using a single vertical control mechanism, instead of multiple axes, motors, motor control and double or triple carriages. Additional benefits are high resolution in the area where the gap between center conductor and probe is small (high GAMMA), smooth increase of proximity between probe and center conductor (basic anti-corona discharge form) and the possibility to compensate for the negative phase slope at higher GAMMA, native to traditional slide screw tuners.

A tunable high-order Bessel low pass filter which is applied to a multi-rate duobinary generation system of an optical communication system. The tunable Bessel low pass filter comprises a variable inductor circuit including a plurality of variable inductors connected in series between an input signal terminal and an output signal terminal and controlled respectively by corresponding inductance control signals, a variable capacitor circuit including a plurality of variable capacitors connected respectively between corresponding connection nodes of the plurality of variable inductors of the variable inductor circuit and a ground terminal and controlled respectively by corresponding capacitance control signals, and a variable capacitor / inductor controller for outputting the corresponding capacitance control signals to the variable capacitors of the variable capacitor circuit and the corresponding inductance control signals to the variable inductors of the variable inductor circuit on the basis of preset values according to a given data rate, respectively. When the data rate of an application system is changed, the tunable Bessel low pass filter controls its filtering characteristics most appropriately to the changed data rate, so as to extend its application range and enhance performance and efficiency of the application system.

The level of the harmonics of oscillation signals for synchronous detection to be inputted to a mixer circuit for converting frequencies is suppressed low. A first integrated circuit component formed with a first mixer circuit for converting frequencies; a second integrated circuit component formed with a second mixer circuit for synchronously detecting intermediate frequency signals and an oscillator transistor circuit; a resonant circuit coupled to the oscillator transistor circuit and forming an oscillator circuit for synchronous detection; an intermediate frequency tuning circuit interposed between the first mixer circuit and the second mixer circuit; and a circuit board for mounting the first integrated circuit component, the second integrated circuit component the intermediate frequency tuning circuit and the resonant circuit in a predetermined block area are provided, wherein the resonant circuit is mounted on the side opposite to the side where the first integrated circuit component and the intermediate frequency tuning circuit are mounted as the second integrated circuit component is sandwiched.

A mounting structure of an electronic circuit unit includes a circuit board provided with a high frequency circuit, a metallic casing mounted on the circuit board to cover the high frequency circuit, an F type connector fixed to the casing and protruding approximately perpendicularly to the circuit board, and a flexible cable having one end portion connected to the circuit board. In a state in which the F type connector passes through a mounting hole formed through a set-side panel to protrude outward, at least one of the casing and the F type connector is fixed to the set-side panel by a fixing member, and the other end portion of the flexible cable is connected to a mother board.

The invention relates to a tuner for converting a RF signal (110) into an IF output signal (202), said tuner comprising a mixer (111) for generating a first IF signal (201), processing means (114) for filtering said first IF signal (201) so as to generate said IF output signal (202). The tuner according to the invention is characterized in that said processing means (114) comprise: a voltage follower circuit (203) receiving said first IF signal (201) for generating a second IF signal (204) at a low impedance, control means (205) for controlling the value of the bias current of said voltage follower circuit (203), a filter (206) having the double resonance frequency for filtering said second IF signal (204) and generating said IF output signal (202). The tuner according to the invention has a strong selectivity for eliminating the residues of frequency components of channels adjacent to the selected channel, as well as a linear frequency response.

A tuner block in which a modulator and an IF / demodulator circuit are integrally formed. The tuner block has a casing for accommodating a tuner, the IF / demodulator circuit and the modulator, and sixteen pins consecutively disposed at an outside of the casing. A number of the pins is reduced as compared with a conventional tuner block by supplying an electrical power to the modulator and the tuner through a common pin, dispensing with pins carrying unnecessary signals and pins which carry no signal and rearranging other pins. Potential for noise and interference between signals is reduced by maximizing displacements of connector pins which carry signals which are likely to interact. A switching arrangement provides for utilizing either a conventional tuner block or a tuner block according to the present invention on a circuit board.

In a receiver, provision is made of a tuneable switchable bandpass filter comprising a primary resonant circuit and a first secondary resonant circuit. A second secondary resonant circuit can be switched into a part of the first primary resonant circuit, thereby producing a second primary resonant circuit. By virtue of the embodiment of the primary resonant circuit, the bandpass filter is switchable in terms of frequency range with little outlay on circuitry and, on account of the individual embodiment of a first and second secondary resonant circuit with individual coupling elements, can be optimized with regard to a constant amplitude response.