Class / Patent application number | Description | Number of patent applications / Date published |
327557000 | Bandpass | 20 |
20080246538 | Negative gm circuit, a filter and low noise amplifier including such a filter - A circuit for synthesising a negative resistance, comprising first and second active devices, the first device having a control terminal connected to a first node, and the second device having a current flow terminal connected to the first node, and the first and second devices interacting with each other such that the circuit synthesises a negative resistance. | 10-09-2008 |
20080252366 | Active Lc Band Pass Filter - An active LC band pass filter | 10-16-2008 |
20080297239 | OPTIMIZED GAIN FILTERING TECHNIQUE WITH NOISE SHAPING - A noise shaping and voltage gain filtering third order electrical circuit and method comprises at least one pair of input resistors; a Frequency Dependent Negative Resistance (FDNR) filter positioned in between the at least one pair of input resistors; a feedback resistor; and an amplifier operatively connected to the feedback resistor and the at least one pair of input resistors, wherein as an electrical signal is introduced to the electrical circuit, the FDNR filter is adapted to filter signal blockers out of the electrical signal prior to the electrical signal reaching the amplifier for signal amplification, wherein the FDNR filter does not contribute noise to a signal-to-noise ratio (SNR) of the electrical signal, and wherein a transfer function of the FDNR filter is substantially elliptical in shape. | 12-04-2008 |
20090102546 | COMPOSITE BAND-PASS FILTER AND METHOD OF FILTERING QUADRATURE SIGNALS - A composite band-pass filter receives a quadrature input signal and passes an intermediate frequency signal while attenuating all other signals including an undesired image signal. The composite band-pass filter is comprised of a continuous time polyphase filter and a discrete time polyphase filter and can amplify signals. The amplification is distributed through out the composite band-pass filter and the amount of amplification may be selected by control signals. The composite band-pass filter has improved dynamic range and noise characteristics, selectable amplification and replaces an external crystal filter. | 04-23-2009 |
20090309649 | ACTIVE BAND-PASS FILTER AND MAGNETIC STORAGE DEVICE - An active band-pass filter has a negative feedback circuit including a series-connection of a band-pass block, a second-order band-elimination block having a denominator polynomial equal to the band-pass block and an amplifier block which amplifies the output of the band-elimination block. The band width can be controlled independently of the frequency, adjustment is made easy, and moreover the circuit configuration can be simplified. | 12-17-2009 |
20100033238 | Method for Reconstructing a Noise-Reduced Periodic Voltage Signal - A method of reconstruction of a fault-reduced voltage signal corresponding in frequency, amplitude and phase position to a sinusoidal input voltage fault-prone in frequency, amplitude and/or phase position is provided. The input voltage is fed to a first band-pass filter including an adjustable resonant frequency and amplification, the output voltage being the fault-reduced voltage signal. A controlled variable is determined for a first controller by determining the scanned differential voltage of the output voltage and the input voltage in zero points of the output voltage, the controller adjusting the resonate frequency of the first band-pass filter such that the differential voltage in the zero points disappears. A controlled variable is determined for a second controller by determining the scanned differential voltage of the output voltage and the input voltage in vertexes of the output voltage, the second controller controlling the amplification of the first band-pass filter such that the differential voltage in the vertexes disappears. | 02-11-2010 |
20100039172 | Ideal-like band-pass filter and single-frequency filter - A near ideal single frequency and band pass filter comprises: an input unit, a filter combination, and an output unit. The input unit accepts an input signal which can be expressed with a mathematical formula f(t). The filter combination comprises a plurality of filters, wherein each filter can generate a control signal and performs the signal filtering process based on the control signal. The control signal can be expressed with a mathematical formula hde(θ). The filter combination processes the input signal based on a set of a plurality of control signals by means of the following formula: | 02-18-2010 |
20100301928 | LOW NOISE, LOW POWER SUBSAMPLING RECEIVER - Techniques for a receiver includes a low noise amplifier, a Q-enhanced bandpass filter on a chip, and an analog to digital converter (ADC) at a sub-sampling speed suitable for an intermediate frequency (IF) signal. In some embodiments, a temperature compensation circuit is included. The receiver has an effective noise level less than 7 dB. In some embodiments a 1-bit ADC is used. In some of these embodiments, one or more switches in the ADC are inverted to cancel charge injection. | 12-02-2010 |
20110140771 | Complex Filter and Calibration Method - A complex filter for processing an in-phase signal and a quadrature-phase signal includes a first low-pass filter, a second low-pass filter, a connection unit between the first low-pass filter and the second low-pass filter, a first compensation resistor and a second compensation resistor. The first compensation resistor and the second compensation resistor are interlacedly coupled to input resistors of the first low-pass filter and the second low-pass filter | 06-16-2011 |
20110291751 | PHASE MATCHING BAND-PASS FILTER USING EXPONENTIAL FUNCTION APPROXIMATION - A The present invention relates to a phase matching band-pass filter using exponential function approximation, comprising an inductor including a parasitic resistor, a first device wherein a first amplifier is connected in a feedback mode, a capacitor including a parasitic resistor, a plurality of filter devices including a second device that is connected with a second amplifier in a feedback mode, and a coupling capacitor that connects the plurality of filter devices; the impedance of the first device has an increasing exponential function relation with a frequency, impedance of the second device has a decreasing exponential function relation with the frequency, and the first device is connected with the second device in parallel. According to the phase matching band-pass filter using exponential function approximation of this invention, conventional inductors and capacitors can be used 0 without modification or use of negative resistance, resulting in a high-performance phase matching band-pass filter. In addition, when a device with impedance characteristics that approximate an exponential function is used, the degree of frequency selection 0 becomes higher than that of conventional filters resulting in filters having high Q values and stability, such as channel selection filters. | 12-01-2011 |
20110304388 | SEMICONDUCTOR INTEGRATED CIRCUIT DEVICE AND WIRELESS COMMUNICATION SYSTEM - Disclosed are a semiconductor integrated circuit device and a wireless communication system that are capable of improving reception sensitivity. The wireless communication system includes, for instance, a first duplexer, a second duplexer, a first low-noise amplifier circuit, and a second low-noise amplifier circuit. A transmission band compliant with a communication standard is split into two segments for use, namely, low- and high-frequency transmission bands. A reception band compliant with the communication standard is split into two segments for use, namely, low- and high-frequency reception bands. The first duplexer uses the low-frequency transmission band and low-frequency reception band as passbands. The second duplexer uses the high-frequency transmission band and high-frequency reception band as passbands. A signal received from the first duplexer and a signal received from the second duplexer are respectively amplified by the first and the second low-noise amplifier circuits, which are respectively provided to handle such signals. | 12-15-2011 |
20120161862 | FILTER CIRCUIT - A circuit and method for filtering a signal. An amplifier ( | 06-28-2012 |
20120212288 | BAND PASS FILTER AND CALIBRATION METHOD FOR BAND PASS FILTER - A band pass filter has a high pass filter into which an input signal is input; an amplifier having an inverting input terminal into which an output of the high pass filter is input, wherein the amplifier amplifies an input voltage between the inverting input terminal and a non-inverting input terminal and outputs an output signal to an output terminal; a first resistor connected between a non-inverting output terminal and the inverting input terminal of the amplifier; a first capacitor having a first terminal that is connected to the inverting input terminal; and an inverting amplifier that inverts a polarity of an output signal from the non-inverting output terminal of the amplifier and outputs the inverted signal to a second terminal of the capacitor. | 08-23-2012 |
20130082766 | DUAL MODE SIGMA DELTA ANALOG TO DIGITAL CONVERTER AND CIRCUIT USING THE SAME - The present invention provides a dual mode sigma delta analog to digital converter (ADC), which only in one hardware implementation, used for low IF and near zero IF receiver. The dual mode sigma delta ADC comprises a first switched-capacitor integrator; a second switched-capacitor integrator; a quantizer; a feedback circuit and a mode device. By switching the mode device on or off, one could easily change the configuration of the disclosed ADC to decide the receiving signal falling in low-IF or near zero IF. | 04-04-2013 |
20130093507 | Op-R, A Solid State Filter - The device described herein proposes an electronic active filter void of capacitors and inductors. The circuit utilizes only operational amplifiers (OP-Amp) and resistors, hence the name Op-R. Although capable of being constructed of lumped circuit elements this filter is intended for integrated circuit (IC) applications. Filtering of signals can be accommodated from dc through the UHF frequency range depending on the selected op-amp ICs. Low pass, band pass, high pass, as well as band reject frequency responses are achievable. Although the circuits described herein are single input-single output, multiple inputs and outputs present no difficulty, being limited only chip space. Temperature and production spread variations are also considered within the realm of tenability. | 04-18-2013 |
20130265106 | TRANSCONDUCTANCE ADJUSTMENT CIRCUIT, CIRCUIT DEVICE, AND ELECTRONIC APPARATUS - A transconductance adjustment circuit includes a reference signal generation circuit that outputs a first signal and a second signal that is different by 90 degrees in phase from the first signal, a replica circuit to which the first signal and the second signal are input and which generates a first output signal and a second output signal, and an adjustment signal generation circuit that outputs a transconductance adjustment signal with respect to the adjustment-targeted circuit and the replica circuit. The reference signal generation circuit generates the first signal and the second signal that change in voltage at between a first voltage level and a second voltage level, based on a clock signal, and outputs the generated first and second signals with respect to the replica circuit. | 10-10-2013 |
20130328623 | LOW POWER ACTIVE FILTER - Some embodiments relate to a band-pass filter arranged in a ladder-like structure. The band-pass filter includes respective inductor-capacitor (LC) resonators arranged on respective rungs of the ladder-like structure. Respective matching circuits are arranged on a leg of the ladder-like structure between neighboring rungs. | 12-12-2013 |
20140203867 | AC INDUCTION NOISE CANCELER - A method for removing noise from an electrical signal in an alarm system using a software filter, the method including the steps of converting the electrical signal from an analog signal into a digital signal, wherein the digital signal includes a series of sampled values, entering a most recent of the sampled values into a circular index containing a number of previously sampled values, multiplying each of the values in the circular index by a predetermined filter coefficient, and summing products of each of the multiplied circular index values and filter coefficients to arrive at a filtered digital signal value. | 07-24-2014 |
20150028944 | OPTIMAL LOW POWER COMPLEX FILTER - The optimal low power complex filter, as a second order complex filter, is based on current amplifiers (CAs) and is utilized to implement a 4th order current-mode filter that can be used for intermediate frequency (IF) applications, such as, for example, low-IF Bluetooth receivers. Fabricated in a standard 0.18 μm CMOS technology, experimental results show that the present design offers improved characteristics over the existing solutions in terms of power consumption and spurious-free dynamic range (SFDR). The 4 | 01-29-2015 |
20150035592 | CORRECTION OF THE PASSBAND OF AN AIR GAP TRANSFORMER - Device for correction of the passband of an air gap transformer with a cut-off frequency, characterised in that it includes a filter adapted to be connected to the transformer in series, and in that the filter is adapted to amplify the signal that it receives from the transformer for frequencies below the cut-off frequency of the transformer, so that the passband of the transformer fitted with the correction device is increased and has a cut-off frequency lower than the cut-off frequency of the transformer. | 02-05-2015 |