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8884714 Apparatus, system, and method for digital base modulation of power amplifier in polar transmitter  
An amplifier receives an amplitude signal of a polar modulated signal at a base terminal of a transistor and receives a phase modulated carrier signal of the polar modulated signal at the base...
8872596 Polar signal generator  
The present invention relates to a polar signal generator and method of deriving phase and amplitude components from in-phase (I) and quadrature-phase (Q) components of an input signal, wherein...
8154357 Modulation for amplitude-modulating a signal  
Modulators for amplitude-modulating signals defined by phase information and envelope codes are provided with first transistors for receiving the phase information and second transistors for...
8031028 Polar signal processor to drive a segmented power amplifier and method therefore  
A circuit for providing AM/PM modulation is described. The circuit provides two drive signals which are later combined in a constructive/destructive fashion. The circuit provides AM modulation...
8004368 Radio frequency amplifier with digital amplitude modulation and method for controlling the delivering of power  
A digital amplitude modulator. The digital amplitude modulator is configured to modulate the amplitude of an input carrier signal based on input digital data and generate a corresponding output...
7812684 Communication apparatus  
A communication apparatus has a local oscillator which performs phase modulation based on a phase component of a baseband signal and outputs a phase modulated signal, a controlling circuit which...
7619487 Polar modulation without analog filtering  
This disclosure relates to systems and methods for polar modulation without analog filters. Digitals filters, a second order hold interpolator and a reconfigurable third order noise shaper can be...
7576623 Amplitude modulation driver  
A circuit includes a first semiconductor device and a second semiconductor device. The first semiconductor device has a first source region, a first gate region, and a first drain region. The...
7327184 Low-power multi-level pulse amplitude modulation driver and semiconductor device having the driver  
A low-power multi-level pulse amplitude modulation (PAM) driver, and a semiconductor device having the same, in which the multi (M)-level PAM driver includes a load unit, first and second current...
7310382 Linearized switch-based power amplifier  
A power amplifier comprises a level-discretization modulator (210) and a mixing and amplifying stage (225), in combination with a properly designed negative feedback path. The feedback path forms...
7119939 Phase modulation circuit, test apparatus, and communication system  
A phase modulation circuit for outputting a modulated signal of an input signal which has been modulated to a desired phase. The circuit includes a light emitting element for emitting light...
7023292 Polar modulation using amplitude modulated quadrature signals  
Polar modulators include a phase splitter, a controller, variable current sources, transistor circuits, and a combiner. The phase splitter splits a RF carrier signal into quadrature component...
6208217 Ask modulator with frequency dependent voltage divider  
An ASK modulator including a switching diode connected in series to a carrier signal transmitting path, a first resistor connected between one end of the switching diode and a digital signal input...
5982446 Video modulator arrangement  
In a single-chip multistandard video modulator arrangement in which audio signals for transmission with video signals are first modulated onto a subcarrier and then combined with the video signals...
5949296 Power supply modulator circuit for transmitter  
The present invention relates to a power supply modulator for a radio transmitter having apportioned input impedance and buffered switching of power modules. A series arrangement of power supply...
5469126 I/Q-modulator and I/Q-demodulator  
An I/Q-modulator or I/Q demodulator circuit in which the modulating signals (2, 3) are input through the output phase transfer branches of the circuit. In relation to the RF-characteristics, a...
5434546 Circuit for simultaneous amplitude modulation of a number of signals  
A method for simultaneously imposing a single modulating signal on a number of constant frequency carriers includes applying the single modulating signal and all of the carriers to a...
5398008 Circuit arrangement for amplitude-modulating the drive signal of a laser  
The universally-applicable circuit arrangement of the invention makes possible an adjustment procedure for holding emitted optical power of a laser constant independent of temperature and aging....
5239275 Amplitude modulator circuit having multiple power supplies  
An amplitude modulator circuit, having an input for receiving an input information signal and an output for providing an output signal, which is proportional to the input signal. The amplitude...
5214397 Modulator using low-pass filter as delay element  
A push-pull modulator stage 70 has two possible transmission paths, an electrically short path (7) and a phase delay path (6) with a phase delay element providing a phase shift of approximately...
5159295 Microwave vector modulator and device for matching a microwave load  
A microwave vector modulator (4) of the reflective type is used to match a microwave load. The adjustable reflection of the vector modulator is obtained by semiconducting surfaces (18, 19, 20,...
5155455 AM/FM modulator in which AM can be converted to FM by vector addition  
A modulator circuit comprises an input for receiving an audio frequency (AF) signal, an oscillator circuit for providing a carrier wave signal, a mixer circuit for mixing the AF input signal with...
5153536 Suppressed carrier modulator formed from two partial modulators each including a phase delay path  
A modulator suitable for 16 quadrature amplitude modulation (QAM) is designed as a double modulator (1), wherein a 16 QAM modulator (39) consists of two double modulators (1). One double modulator...
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...
5006811 Dual quadrature frequency converter  
A method and apparatus for modulating or demodulating a radio frequency (RF) signal which incorporates a pair of quadrature couplers. In demodulating an RF signal, an LO signal and the RF signal...
4952890 Phase modulation compensated amplitude modulator using digitally selected amplifiers  
An RF amplitude modulated amplifier system is presented incorporating a plurality of RF amplifiers which are compensated for unwanted phase modulation. The system includes a common RF driver for...
4635003 Oscillator mixer circuit with reaction-tree coupling  
An oscillator and mixer circuit of an integrated UHF/VHF modulator circuit includes a single active oscillator circuit to be connected to frequency-determining passive circuits for UHF and...
4580111 Amplitude modulation using digitally selected carrier amplifiers  
An amplitude modulator (10) is disclosed which generates an amplitude modulated carrier signal by selectively combining varying numbers of other carrier signals. A circuit (20) is included which...
4481490 Modulator utilizing high and low frequency carriers  
To minimize carrier leak in the modulation of voice frequencies to the desired line frequency for a carrier system, a first balanced modulator is operated at a low frequency where low carrier-leak...
4399558 Cascaded digital broadcast transmitter  
A digital AM broadcast transmitter features a plurality of stages that are controlled by a digital signal representing an audio modulating signal. At least some of the stages are cascade coupled...
4346354 Amplitude modulator using variable width rectangular pulse generator  
A method and apparatus for amplitude modulating a carrier signal with an audio or information input signal utilizes an arcsine generator to cause the envelope of the carrier to follow the input...
4336615 Linear loading for PWM filter  
An AM broadcast transmitter uses a PWM modulator that requires a pulse width filter. It has been found that the filter load varies over the modulation cycle resulting in distortion. To overcome...
4319359 Radio transmitter energy recovery system  
An AM transmitter includes an RF signal generator and a switching-type RF signal amplifier. The RF amplifier output depends upon the energizing voltage applied thereacross, so it acts as a...
4300019 Method and apparatus for multiplying an electrical signal  
A multiplier circuitry which multiplies an electrical signal by a multiplier signal comprises an oscillator which oscillates at a frequency having a predetermined relationship with respect to the...
4160960 Power-dividing and modulating arrangement  
A power divider and modulator is disclosed comprising a HF signal source which supplies a carrier signal to a pair of 1/4λ transformers each terminated with a variable impedance, whose impedance...
4152671 Oscillator-modulator apparatus and method therefor  
A radio frequency oscillator-modulator for use in a video game includes a folded metal shield box having a slot on one of its ends in which a similarly slotted printed circuit board containing the...
4122415 AM transmitter with an offset voltage to the RF stage to compensate for switching time of the modulators  
An AM transmitter of the type including apparatus for generating a subcarrier signal, pulse width modulating this subcarrier with audio, amplifying this resulting pulse width signal using active...
4052682 Multiple oscillator modulator circuit  
A plurality of oscillator-modulator combinations is incorporated into a monolithic integrated circuit. A single pole multiple position switch is used to energize a single oscillator at a time, and...
3995236 Double sideband modulator  
A modulator employs a pair of variable RF attenuators to produce a double sideband, suppressed carrier output. The attenuator devices are PIN diodes which are rendered alternately conductive in...
3974460 High frequency modulator, such as an amplitude modulator, including a frequency multiplier  
A high-frequency modulator circuit including a frequency multiplier comprised of a first differential amplifier for receiving a base oscillating signal and for multiplying the frequency of the...
3940716 Double-balanced modulating and demodulating apparatus  
A double-balanced modulating and demodulating circuit is disclosed for producing from carrier and modulating input signals at least one double sideband suppressed carrier signal. A pair of...
3898590 Progressive amplitude modulator  
An amplitude modulator, which has a combining circuit for combining a carrier wave with a power modulating signal to control the amplitude of an output wave of carrier frequency in accordance with...
3810047 INDUCTORLESS AMPLITUDE MODULATOR AND DEMODULATOR APPARATUS  
An inductorless modulator-demodulator circuit is disclosed including a pair of symmetrical channels each containing a control device biased to Class AB operation. Components of a first input...
3737809 MODULATED CARRIER FREQUENCY SOURCES  
An amplitude modulated carrier frequency source has a first modulator and a first differential amplifier in a feedback loop of the first modulator, and a second modulator and a second differential...
3723910 MIXING CIRCUIT UTILIZING LINEAR RESISTANCES  
The mixing circuit employs the linear portions of the voltage-current characteristics of a plurality of field-effect transistors to amplitude modulate a first signal, having a first frequency,...
3636478 ACTIVE BALANCED MODULATOR CIRCUIT  
An active balance modulator circuit wherein the active switching elements of the modulator circuit are switched suddenly or in jumps as if controlled by a square wave carrier signal but utilizing...
3588748 MODULATOR EMPLOYING A PLURALITY OF UNIDIRECTIONAL ADMITTANCE CIRCUITS FOR GENERATING A PIECEWISE LINEAR APPROXIMATION OF THE DESIRED MODULATION CURVE  
3582828 CHARGE STORAGE DIODE MODULATORS AND DEMODULATORS  
Circuits for the modulation or demodulation of radio frequency signals comprising a charge storage diode which can provide a reverse current with a current-time integral equal to that of a forward...
3559106 MODULATOR THAT DEVELOPS AND REINFORCES ONE SIDEBAND WHILE DEVELOPING AND ATTENUATING A SECOND SIDEBAND  
3528037 CIRCUIT AND METHOD FOR CORRECTION OF TRANSMISSION DISTORTION IN AN AMPLITUDE MODULATION SYSTEM  

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