Bizarre Patents
A helium-filled sun shade for protecting individuals engaged in outdoor activities.
PatentStorm News
Make the Most of Our Site
See this month's Top Inventors and Most Cited Patents.
Stay on top of the latest innovations by subscribing to an RSS feed.
Registered users: Manage your profile.
| Number | Title | Issue Date |
| 7570127 | Method and system for spur suppression in modulators An IF receiver receives a tapped portion of a modulated communication signal. A processor, local with respect to the IF receiver, receives an interrupt from a main processor instructing it to evaluate the power levels of desired and undesired components of the commu... | 08/04/2009 |
| 7382887 | Method and device for reducing high frequency error components of a multi-channel modulator A method and device for reducing error components of a multi-channel modulator. The method comprises the steps of inverting substantially half of the channels of a modulator, and reducing error components between said inverted channels and said non inverted channels... | 06/03/2008 |
| 7187911 | Calibrated PLL for wide band communication semiconductor integrated polar loop transmitter The invention provides a communication semiconductor integrated circuit (RF IC) that, when a transmission oscillator is incorporated into a semiconductor chip, secures the oscillation operation over a wide frequency range, prevents a deterioration of a transmission ... | 03/06/2007 |
| 7127020 | Frequency synthesis loop having controlled loop gain A method and apparatus for generating a burst FSK signal having precisely shaped transitions between modulation states. The apparatus uses feedforward compensation of phase gain and phase preemphasis coefficients for compensating the frequency conversion gain of the... | 10/24/2006 |
| 7123666 | Gaussian minimum shift key transmitter with feedforward phase compensation A method and apparatus for generating a burst FSK signal having precisely shaped transitions between modulation states. The apparatus uses feedforward compensation of phase gain and phase preemphasis coefficients for compensating the frequency conversion gain of the... | 10/17/2006 |
| 7123665 | Method and apparatus for measuring phase error of a modulated signal A method and apparatus for generating a burst FSK signal having precisely shaped transitions between modulation states. The apparatus uses feedforward compensation of phase gain and phase preemphasis coefficients for compensating the frequency conversion gain of the... | 10/17/2006 |
| 7062236 | Transmitter circuits A polar loop transmitter includes separate phase and envelope paths providing a linearising scheme for an efficient non-linear power amplifier. Loop filters are included in each of the phase and envelope paths to enable the path characteristics to be matched to one ... | 06/13/2006 |
| 6950636 | Power amplifier control driver having over-current protection and linear control A linear power control loop for a power amplifier is disclosed. Embodiments of the invention linearly control the power amplifier output, prevent the power amplifier from failure induced by excessive supply current by reducing power amplifier bias current, and provi... | 09/27/2005 |
| 6924711 | Multimode modulator employing a phase lock loop for wireless communications A phase-amplitude modulator for mobile communications employs a phase lock loop as an input to a nonlinear power amplifier providing phase information with amplitude information used to modulate the power amplifier output to synthesize phase-amplitude for the RF tra... | 08/02/2005 |
| 6914987 | Audio amplifier with voltage limiting in response to spectral content Audio signals are reproduced with consistent perception of total harmonic distortion even with varying spectral content of a particular audio signal without separately limiting different frequency bands within the audio signal. A distortion threshold representative ... | 07/05/2005 |
| 6907085 | Activation method of communications apparatus with a non-linear distortion compensation device First, a digital section constituting a linearizer is activated. Then, a feedback loop for updating a distortion compensation coefficient is opened. Then, the analog section on the antenna side is activated from an ADC, including a PA, etc., or a DAC. Then, both the... | 06/14/2005 |
| 6844788 | Polar loop transmitter A polar loop transmitter circuit arrangement includes a circuit input, a circuit output, a controllable signal source, a modulator connected between the signal source and the output, a first amplifier having its input connected to the circuit input, a second amplifi... | 01/18/2005 |
| 6657510 | Corrective phase quadrature modulator system and method A system and method for producing a phase corrected M-QAM signal is described. In one embodiment, a phase-correcting M-QAM modulator comprises a feedback loop for dynamically adjusting the phase relationship between the two carrier signals as a function o... | 12/02/2003 |
| 6614854 | System and method for adaptive predistortion Distortion introduced into a multiamplitude signal format or amplitude and phase signal format by a high power microwave amplifier is compensated by a system which adapts itself to non-linearities present in the amplifier and predistorts the input signals... | 09/02/2003 |
| 6567478 | Radio apparatus having distortion compensating function In a radio apparatus which compensates for non-linear distortion of a transmission power amplifier, a distributor feeds back the output signal of the transmission power amplifier, an error-signal estimating arithmetic unit digitally estimates an error sig... | 05/20/2003 |
| 6518849 | Dynamic delay compensation versus average switching frequency in a modulator loop and methods thereof The present invention monitors the average switching frequency at the output of the comparator and adjusts the delay compensation accordingly. That is, the switching frequency monitoring circuit looks at the average switching frequency and maintains the a... | 02/11/2003 |
| 6414560 | Loop delay compensation for a digital power amplifier A modulator loop is described having an associated band pass frequency range and including a switching stage having a first delay associated therewith. The modulator loop also includes a modulator stage having a feedback input. The output of the modulator... | 07/02/2002 |
| 6373346 | Laser driver pre-emphasis and de-emphasis method and/or architecture with tuning and duty cycle control An apparatus comprising a modulator circuit, a first and a second control circuit. The modulator circuit may be configured to generate a modulated differential output signal in response to a differential input signal. The first control circuit may be conf... | 04/16/2002 |
| 6362702 | Controlled self-oscillation modulator and power conversion system using such a modulator A controlled oscillation modulator includes a comparator and a power amplification stage for pulse modulation, and a higher order oscillating loop comprising first feedback means (21) and first forward means (22) securing stable oscillating conditions. Th... | 03/26/2002 |
| 6285255 | Adaptive compensation for carrier signal phase distortion Apparatus and method are presented for adaptively compensating for carrier signal phase distortion caused by amplitude modulating an RF carrier signal. A modulator-amplifier network receives an RF carrier signal and modulates it by a received amplitude va... | 09/04/2001 |
| 6169463 | Quadrature modulator with set-and-forget carrier leakage compensation A quadrature modulator with set-and-forget carrier leakage compensation. The quadrature modulator comprises an in-phase and a quadrature branch. In the in-phase and quadrature branches, real-time digital signals are converted to analog signals, the analog... | 01/02/2001 |
| 6141390 | Predistortion in a linear transmitter using orthogonal kernels A system for linearly transmitting an amplified output signal using predistortion is disclosed. The system uses a straight inverse modeling scheme with orthogonal predictor variables to more easily and accurately determine the inverse of the distortion ca... | 10/31/2000 |
| 5909153 | Method and apparatus for compensating for delays in modulator loops A modulator loop designed to operate in a frequency range of interest is described. The loop includes a loop output terminal and a switching stage, the output of which is coupled to the loop output terminal. The switching stage has a first delay associate... | 06/01/1999 |
| 5900778 | Adaptive parametric signal predistorter for compensation of time varying linear and nonlinear amplifier distortion A high power amplifier system includes an on-line adaptive predistorter for generating predistorted complex data signals to a high power amplifier in response to receiving incoming complex data signals from a remote source. The predistorted complex data s... | 05/04/1999 |
| 5883551 | Quadrature modulator malfunction estimator and modulator stage using it A quadrature modulator including two mixers to which two carrier signals are applied and to each of which a modulating signal is applied, output signals of the mixers being applied to a combiner to constitute a modulated signal. A defect estimator for the... | 03/16/1999 |
| 5798674 | Band Limited AM modulator using linear power amplification A band limited Amplitude Shift Keyed (ASK) modulator employing linear modulation and an efficient Class C power amplifier. Band-limited operation is provided by filtering a digital baseband input signal prior to modulation. Closed loop feedback is employe... | 08/25/1998 |
| 5768699 | Amplifier with detuned test signal cancellation for improved wide-band frequency response A feed forward amplifier circuit which includes a main amplifier, an error correction circuit producing a message error signal, an error amplifier for producing an amplified message error signal that is then subtracted from the amplified and distorted mes... | 06/16/1998 |
| 5748678 | Radio communications apparatus A radio communications apparatus employs a training routine for optimizing performance and has a modulator (64, 66) to modulate a radio channel with digital information, to provide baseband signals (I, Q) at a first data rate. A power amplifier (36) ampli... | 05/05/1998 |
| 5719527 | Method and apparatus for amplifying, modulating and demodulating A highly efficient linear amplifier and/or modulator and demodulator comprising first and second feedback loops is provided. Each loop processes a component of the input signal and the component signals are recombined at, for example, a summing junction 1... | 02/17/1998 |
| 5699383 | High-power linear amplification using periodically updated amplitude and phase correction values In a high-power transmitter, an input complex signal is multiplied in a complex multiplier by control signals. The output complex signal from the multiplier is converted to a high frequency signal and amplified by a power amplifier for transmission. The a... | 12/16/1997 |
| 5663691 | Estimator for estimating an operating defect in a quadrature modulator, and a modulation stage using the estimator An estimator for estimating an operating defect in a quadrature modulator, including two mixers to which respective carrier signals are applied, and to which respective modulating signals are also applied. The output signals from the mixers are applied to... | 09/02/1997 |
| 5661442 | Amplitude control system having parallel integrating signal paths An amplitude control system uses a pair of parallel integrators to rapidly adjust the amplitude of a test signal between two precisely determined power levels in an RF signal generator. The amplitude control system initializes a first power level by switc... | 08/26/1997 |
| 5450043 | Quadrature modulator with distortion compensation A quadrature modulator multiplies two carriers which are 90° out of phase with each other by a sine component and a cosine component of a baseband signal, respectively, adds the product signals to each other, and amplifies the sum signal to produce a qua... | 09/12/1995 |
| 5396196 | Quadrature modular with adaptive suppression of carrier leakage A carrier leakage suppression circuit is disclosed which adaptively suppresses carrier leakage in a signal processing device which modulates a carrier signal with an in-phase baseband signal and a quadrature baseband signal to generate a radio frequency (... | 03/07/1995 |
| 5247542 | QPSK power amplifier distortion correction system A quadrature phase-shift keying modulator produces a QPSK signal which is amplified by a power amplifier. The amplitude gain of the power amplifier is controlled in response to an amplitude difference between the QPSK signal output by the modulator and th... | 09/21/1993 |
| 5105164 | High efficiency UHF linear power amplifier An RF amplifier for a phase and envelope varying signal employs a class C operated device for high efficiency. In order to improve the linearity of the class C operated device, a signal corresponding to the envelope of the amplifier output is formed and a... | 04/14/1992 |
| 5095290 | Amplitude modulator having negative feedback circuit for reducing distortion Modulator circuit (MOD) with a modulator proper and a correction signal generator. The modulator proper comprises the cascade connection of an amplifier (T11, T21, CS11, T12, T22, CS12) and a first switching circuit (R11, T31, T51, R12, T32, T52), while t... | 03/10/1992 |
| 5012208 | Quadrature modulator having compensation for local oscillator leak The invention relates to a quadrature modulator comprising a circuit for the compensation of a local oscillator leak signal in an output signal of the modulator, which circuit adds different compensation voltages to two modulation signals. To provide an a... | 04/30/1991 |
| 4952886 | RF power-control circuit An improved circuit for controlling the output power level of a radio frequency (RF) amplifier is disclosed. The circuit samples the output of an RF amplifier. The sample is amplitude modulated at a preselected modulation frequency and is passed to a dete... | 08/28/1990 |
| 4939483 | Modulation frequency response stabilized amplitude modulation circuit A frequency response stabilized amplitude modulation circuit includes a variable gain amplitude modulator producing an output signal having an amplitude proportional to a product of amplitudes of input carrier, modulating and gain control signals. An enve... | 07/03/1990 |
