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7460612 Method and apparatus for a fully digital quadrature modulator  
A novel apparatus and method for a fully digital quadrature architecture for a complex modulator. The complex modulator can substitute for existing prior art analog quadrature modulator structures...
7327202 Optimization for an IQ modulator  
An IQ modulator's performance is optimized through determination of suitable control parameters by the application of known DC biases as the I and Q inputs. Also known are the relative amplitude...
7257166 Data communication apparatus and method based on orthogonal frequency division multiple access  
A data communication apparatus and method based on OFDMA are provided. In a first user transmitting unit through which a user transmits user information to a base station in units of first symbol...
7095996 Wireless communication system, and demodulation method and data rate control method therefor  
A transmitter and a receiver share a maximum number of transmission bits per symbol as a parameter. The transmitter modulates an encoded and interleaved transmission signal in accordance with a...
7061341 System for highly linear phase modulation  
System for highly linear phase modulation. Apparatus is provided for linear phase modulation utilizing a phase-locked loop (PLL). The apparatus includes a PLL utilizing fractional N synthesis to...
6831526 Phase and amplitude digital modulation circuit and method  
A method and a circuit for modulating a carrier signal (Se) with a signal (SCj) having at least a modulation cell (CMi) by phase shift for receiving two digital control signals (Scji, SCji 2 )...
6727771 Semiconductor integrated circuit device with variable gain amplifier  
A semiconductor integrated circuit device includes an orthogonal modulator that maintains carrier leak characteristics regardless of attenuation of an output signal level. The orthogonal modulator...
6700453 Amplitude imbalance compensation of quadrature modulator  
A method and an arrangement for compensating for amplitude imbalance of a quadrature modulator including: determining a first correlation on the basis of a first modulation signal and an output...
6587010 Modulated radio frequency signal generation method and modulated signal source  
A modulated signal source for implementing A modulated signal method of a generating a modulated signal having a radio frequency based upon a linear mixing of signals is disclosed. An in-phase...
6433647 Low noise I-Q mixer  
A low-noise quadrature phase I-Q modulator having a pair of Gilbert cell input stages driven by a feed voltage line and receiving in input respective square wave command signals coming from a local...
6373345 Modulator structure for a transmitter and a mobile station  
A modulator having a high signal-to-noise ratio. The modulator comprises a switching arrangement and a driver arrangement coupled to the switching arrangement, said driver arrangement comprising...
6359523 Orthogonal modulator, mobile terminal and communication system  
An orthogonal modulator capable of eliminating an offset component between an I signal and a Q signal. The orthogonal modulator includes a generation circuit for generating a plurality of base band...
6232843 Plural coupled microwave oscillators providing phase shifted output signals  
A signal generator for producing a plurality of signals having the same frequency but a constant phase difference includes first and second cavity oscillators coupled to each other via an...
6163230 Phase-shift keying electronic circuit with distributed structure  
The invention concerns a modulating electronic circuit with m phase status m≥2 comprising a distribution line (6) with n similar dephasing cells (Ci) n≥2, each comprising a transistor supplying...
6147563 Coupled cavity oscillator producing output signals with a constant phase difference  
An improved method and system for generating quadrature phase shift keying signals for use in data transmission is provided. A pair of oscillators are slaved to the transmit frequency and produce...
5949297 Balanced modulator  
A balanced modulator has a pair of diodes, a plurality of line patterns including a balance-to-unbalance converter, the line patterns including lines extending toward and connected to the diodes,...
5949826 Data transmission and reception system  
A data transmission and reception system according to this invention comprises a transmitter for transmitting data by modulating transmit data and a receiver for receiving and demodulating a signal...
5867072 Biphase modulator with balun design  
A double-balanced microwave biphase modulator circuit is provided with a first balun for transforming the unbalanced RF Input impedance to a balanced diode impedance and providing direct current...
5852389 Direct QAM modulator  
A direct QAM modulator for generating a high power QAM modulated signal at microwave frequencies comprises a hybrid to create the required RF signals for I and Q paths. In each path, a rat-race...
5847623 Low noise Gilbert Multiplier Cells and quadrature modulators  
A Gilbert Multiplier Cell includes an emitter-coupled transistor pair and a pair of cross-coupled emitter-coupled transistor pairs. A filter couples the emitter-coupled transistor pair to the pair...
5844449 Gilbert cell phase modulator having two outputs combined in a balun  
A phase modulator having a Gilbert cell mixer can be used in frequency ranges from a microwave frequency band of several GHz to a millimeter wave band of several 10 GHz. Two output signals Vout1,...
5708399 Modulator and frequency multiplier for use therein  
A modulator that effectively suppresses carrier leakage is disclosed. The modulator includes a frequency multiplier, a phase shifter and an orthogonal modulator. The frequency multiplier outputs...
5574409 Apparatus and method for adjusting microwave BPSK modulator and mixer  
Microwave two-phase modulator and mixer each comprising a balance/unbalance transformer section to which a microwave signal is applied; a synthetic/branching line section which is connected to the...
5504461 High speed slotline BPSK modulator  
A slotline binary phase shift keyed (BPSK) modulator that is capable of operating at high frequency with relatively low sensitivity to terminating impedance. The slotline BPSK modulator comprises a...
5504465 Microwave modulator having adjustable couplers  
A multifunction microwave modulator circuit has an input signal splitter to provide two equal amplitude signal components. A phase quadrature relationship between the two signal components is...
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...
5463355 Wideband vector modulator which combines outputs of a plurality of QPSK modulators  
A vector modulator that sums outputs of a plurality of quadrature-phase-shift-key (QPSK) modulator elements, each controlled by two digital input signals and a single local oscillator. The local...
5455544 Low power consumption binary phase-shift-keyed (BPSK) modulator using reflective electronic switching techniques  
A low power consumption BPSK modulator uses only a single input transformer which is not required to be center-tapped, and a switching arrangement including four junction field effect transistors....
5453720 Digital adjustable phase modulator and method  
A digital adjustable phase modulator and method includes a first circuit path and a second circuit path for a signal. A fixed bias voltage is coupled to the first circuit path and to the second...
5451913 Compact MMIC tunable biphase modulator and method  
An apparatus for providing electronically tunable biphase modulation. The apparatus includes an input for supplying a signal to be modulated and a coupler including first, second, third and fourth...
5446422 Dual mode FM and DQPSK modulator  
A dual-mode radiotelephone terminal includes a π/4-shift DQPSK modulator (11). A dual-mode modulation is achieved by mixing an output of a transmitter oscillator (16) with an output of an offset...
5428320 Biphase modulator and method without matching elements  
A biphase modulator without matching elements includes a Lange coupler (5) including first, second, third, and fourth ports (1,2, 3, 4), where the first port (1) receives a RF input signal. FETs...
5412351 Quadrature local oscillator network  
A compact local oscillator network for use in a quadrature modulator and/or demodulator is presented. Single side band circuitry is configured to produce quadrature signals with a high degree of...
5367271 Quadrature modulator having phase shift and amplitude compensation circuits  
A quadrature modulator includes a 0°/90° phase shifter including only resistors, capacitors, and transistors that separates an input carrier wave into two carrier waves having a phase difference...
5311151 I/Q modulator and demodulator having a single bridge  
An IQ modulator/demodulator wherein the 90° phase quadrature branches of an input signal are connected to different terminals of a common bridge, from which also the quivalents I and Q signals are...
5231364 Phaseshift network for an IQ modulator  
A phaseshift network (2) exhibits approximately equal impedances to the outputs of an IQ mixer (10), over a range of modulation frequencies (Fm). The phaseshift network furthermore exhibits an...
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...
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...
5126698 Phase modulator operated in saturation and with small angle modulation  
An input carrier signal is applied to two paths. The two paths are such that the phase difference between the output of the two paths is substantially 90°. At least one of the two paths responds...
5122765 Direct microwave modulation and demodulation device  
A microwave circuit intended for either direct modulation or direct demodulation of a microwave link communications signal is characterized in that a local oscillator (8) is incorporated in the...
5081432 Variable bi-phase modulator circuits and variable resistors for microwave signals  
A variable bi-phase modulator circuit for microwave signals includes a quadrature power divider (1) having signal input and output ports (2 and 3) and two control ports (4 and 5), and two variable...
5045816 Binary phase shift key modulator with programmable level control  
A BPSK modulator for modulating a data signal onto a carrier signal comprises first and second transistors connected in a mirror configuration and a center tap transformer. The collectors of the...
5039959 Phase switching circuit  
A phase switching circuit adapted for high frequency applications which is operative for shifting the phase of an input signal either by 0° or 180° in response to a control signal. The switching...
4726039 Constant amplitude PSK modulator  
A phase modulating system for providing PSK modulation with minimum sidelobe generation. Phase changes, during the phase transition period, are accomplished with a minimum of carrier amplitude...
4656647 Pulsed bi-phase digital modulator system  
A short pulse of a small leading phase angle deviation of the carrier frequency at the start of a clock period and a short pulse of a small lagging phase angle deviation of the carrier frequency at...
4612518 QPSK modulator or demodulator using subharmonic pump carrier signals  
The present invention relates to a QPSK modulator or demodulator for modulating two different input bit streams with a subharmonic pump carrier signal to produce an appropriately encoded QPSK...
4565980 PSK Modulator with preset amplitude and phase corrections for each phase  
A phase modulation method and apparatus for modulating the phase of a carrier wave in accordance with a binary modulating signal to produce a modulated wave. At least one of the amplitude and the...
4528526 PSK modulator with noncollapsable output for use with a PLL power amplifier  
A PSK modulator for use with a phase lock locked loop power amplifier circuit in a communications transmitter wherein one signal channel of the modulator includes a delay equal to one-fiftieth of...
4504802 Digital PSK modulator for modem  
An improved four-phase differential phase shift keyed modulator for use in a modem is shown. A microprocessor (15) generates two vectors of equal frequency and equal magnitude, but different...
4361817 Bi-phase modulator/demodulator  
A bi-phase modulator/demodulator circuit for converting uni-polar to bi-polar signals. The circuit can be used to bi-phase modulate a continuous wave (CW) input signal or to demodulate a bi-phase...
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