Abstract: There is provided a small-size, low-power-consumption intermittent operation circuit capable of obtaining an output waveform having a rapid rise and fall. The intermittent operation circuit includes an active circuit (106), a first control signal generation circuit (101) for generating a first control signal (S1) for controlling the operation start and the operation end of the active circuit (106), a second control signal generation circuit (102) for generating a second control signal (S2) causing the active circuit (106) to perform ringing vibration and controlling the frequency and the amplitude value of the ringing vibration, and a timing adjusting circuit (103) for adjusting the input timing of the first and the second control signal (S1, S2) into the active circuit (106) so that the ringing vibration and the safety vibration are outputted continuously from the active circuit (106).

Abstract: Embodiments of the present invention include amplitude-modulated or polar-modulated radio frequency (RF) power amplifier circuitry, in which an envelope power supply input to an RF power amplifier is powered by a pre-distorted amplitude modulation (AM) power supply. The pre-distorted AM power supply receives an AM signal, which is then pre-distorted and amplified to provide an AM power supply signal to the RF power amplifier. The pre-distortion of the AM signal is used to improve the linearity, the efficiency, or both, of the RF power amplifier. The pre-distortion provides a feed-forward system, which may allow use of a reduced bandwidth pre-distorted AM signal to an AM power supply and a reduced bandwidth AM power supply, which may increase efficiency.

Abstract: Signal modulation apparatus for applying a modulation signal to a carrier signal, the apparatus comprising: an amplitude modulator for modulating the amplitude of the carrier signal in accordance with a control signal; first mixing means for mixing together fractions of the carrier signal before and after action of the amplitude modulator to produce a first detection signal indicative of the amplitude modulation applied by the amplitude modulator; and detection means for comparing the control signal with a first detection signal to evaluate distortion in the first detection signal as compared with the control signal.

Abstract: A test apparatus includes digital modulators provided in increments of multiple channels. A baseband signal generator performs retiming of data input as a modulation signal for the in-phase (quadrature) component, using a timing signal the timing of which can be adjusted, thereby generating a baseband signal. A driver generates a multi-value digital signal having a level that corresponds to the baseband signal output from the baseband signal generator. A multiplier amplitude-modulates a carrier signal with the multi-value digital signal. An adder sums the output signals of the multipliers.

Abstract: A phase locked loop comprising: an oscillator for generating an output signal of a frequency that is dependent on an input to the oscillator; sampling means for generating a sequence of digital values representing the output of the oscillator at moments synchronised with a reference frequency; a difference unit for generating a feedback signal representing the difference between successive values in the sequence; and an integrator for integrating the difference between the feedback signal and a signal of a desired output frequency; the signal input to the oscillator being dependent on the output of the integrator.

Abstract: Apparatus for generating a modulation signal for use in modulating the power supply of a power amplifier uses coarse and fine control for controlling the amplitude of the modulation signal, and thereby controlling the output power of the power amplifier. The modulation signal may be generated in the digital domain and converted to the analog domain by a digital-to-analog converter, with the digital-to-analog converter providing the fine control and a variable gain amplifier providing the coarse control of the analog signal.

Abstract: Apparatus and methods for improving the performance of a modulator, typically in an I/Q modulation system, are described. Input I and Q current modulation signals may be processed to generate a sign signal and a magnitude signal, with the magnitude signal selectively applied to the inputs of a mixer based on the sign signal so as to generate respective I and Q modulation signal components. These may then be combined to generate a composite modulation signal.

Abstract: In a method for the production of a radio-frequency signal modulated as a function of a low-frequency digital data stream, a clock signal is provided having a frequency that is at least four times as high as the frequency of the radio-frequency signal to be produced. The clock signal is used for mixing the low-frequency data stream with a cyclical numeric sequence representing a continuous sinusoidal or co-sinusoidal series. A circuit arrangement implements such a method to produce a radio-frequency signal modulated as a function of a low-frequency digital data stream, and a magnetic resonance tomography system employs such a circuit arrangement.

Abstract: A digital amplitude modulator is configured to modulate the amplitude of an input carrier signal based on input digital data and generate a corresponding output signal. The digital amplitude modulator includes a first variable gain amplifier for receiving the input carrier signal and generating a corresponding first amplified carrier signal, a second variable gain amplifier for receiving the input digital data and generating corresponding digital amplitude control data and a plurality of selectively activatable amplifier stages. Each amplifier stage receives a replica of the first amplified carrier signal and generates a corresponding second amplified carrier signal when activated. The output signal corresponds to a combination of the second amplified carrier signals generated by the activated amplifier stages.

Abstract: A modulation system includes an amplitude modulation path and a phase modulation path coupled to the amplitude modulation path. One of the amplitude modulation path and the phase modulation path receive a reduced current such that the reduced current reduces power consumption by the system. Preferably, the amplitude modulation path receives the reduced current. The amplitude modulation path has a first set of components and a second set of components. The first set of components consumes less power by using slower operation. The second set of components consumes less power by effectively not operating, or being turned off.

Abstract: To reflect advantages of a constant phase modulation waveform, the invention provides a pulse amplitude modulated PAM waveform that is a superposition of Q0?2L?1 PAM component pulses in each symbol interval such that a significant portion of signal energy over each symbol interval is within the Q0 PAM component pulses. The present invention distributes most signal energy in one pulse and progressively lower energies in the remaining Q0?1 pulses of a symbol interval. The Laurent Decomposition is a special case of the present invention, but the present invention exhibits the energy distribution of the Laurent Decomposition in non-binary CPM waveforms and in multi-h (binary and non-binary) CPM waveforms, where h is a modulating index. All energy is distributed among only Q=2L?1 pulses in each symbol interval, though only Q0<Q pulses may in fact be transmitted in certain embodiments. A method, transmitter, receiver, and computer program are disclosed.

Abstract: The present invention includes a digital quadrature rate converter and an oversampling interpolator, which are used to receive digital quadrature modulation data at one clock rate and to provide oversampled digital quadrature modulation data at a higher clock rate. Rate conversion and oversampled interpolation are used to accommodate systems with multiple clock frequencies and to generate modulation signals with low distortion. Some embodiments of the present invention add timing control to the oversampled interpolation. Some embodiments of the present invention may combine the rate conversion, oversampled interpolation, and timing control operations into a single digital circuit.

Abstract: Methods and apparatus are described for generating and receiving amplitude and differential-phase encoded signals in which the number of phase states at a given amplitude level is always less than or equal to that at a higher amplitude level and at least two amplitude levels have different numbers of phase states.

Abstract: Efficient PAM transmit modulation is provided by a PAM modulator that includes an oscillator (404) that provides a clock signal, CKV, (408). The clock signal 408 and a delayed version (CKV_DLY) 420 of the clock signal are provided to a logic gate (414). The output of logic gate (414) is used as a power amplifier input signal (PA_IN) for radio frequency power amplifier (416). Depending on the relative time delay of the CKV clock signal (408) and the CKV_DLY delayed clock signal (420), the timing and duty cycle of the logic gate (414) duty cycle can be controlled. The duty cycle or pulse-width variation affects the turn-on time of the power amplifier (416); thereby establishing the RF output amplitude.

Abstract: A signal conversion device, a radio frequency identification (RFID) tag, and a method for operating the RFID tag. The RFID tag has an electrically erasable programmable read-only memory module for storing RFID tag information and transmitting the RFID tag information; an information comparison module coupled to the electrically erasable programmable for receiving the RFID tag information and demodulation information, comparing the RFID tag information with the demodulation information, and generating a driving signal; and a pulse oscillation module coupled to the information comparison module for receiving the driving signal, and transmitting pulse oscillating signals to the electrically erasable programmable read-only memory module, so as to allow the electrically erasable programmable read-only memory module to transmit the RFID tag information.

Abstract: A modulator includes a first converter, a second converter and a mixer. The first converter is configured to receive a first bit and provide a first current that is a function of the first bit. The second converter is configured to receive a second bit and provide a second current that is a function of the second bit. The mixer is configured to receive an input current that is a sum of the first current and the second current and a frequency signal and provide an output signal that is a function of the input current and the frequency signal.

Abstract: 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 first gate region and the first drain region are separated by a first distance. The second semiconductor device has a second source region, a second gate region, and a second drain region. The second gate region and the second drain region separated by a second distance. The first distance is greater than the second distance.

Abstract: A quadrature LINC transmission system processes a baseband input signal for transmission as a linearly amplified RF signal. An in-phase LINC element processes an in-phase baseband signal into an in-phase RF signal. A quadrature LINC element processes a quadrature baseband signal into a quadrature RF signal. An output combiner combines the in-phase RF signal with the quadrature RF signal to provide the linearly amplified RF signal. The in-phase LINC element has a constant envelope decomposition block for decomposing the in-phase baseband signal into in-phase baseband constant envelope components. Two up-converters convert the in-phase baseband constant envelope components to in-phase RF constant envelope components. Two non-linear amplifiers amplify the in-phase RF constant envelope components. A combiner combines the amplified in-phase RF constant envelope components to yield the in-phase RF signal. The quadrature LINC element is similar to the in-phase LINC element and provides the quadrature RF signal.

Abstract: A hybrid modulator apparatus includes a modulator that amplitude modulates a power supply signal. A correction circuit coupled in parallel with the modulator reduces errors caused by the modulator. In one embodiment the modulator includes a digital pulse-width modulator (PWM) and a buck converter. The K most significant bits (MSBs) of N-bit input digital words are used by the digital PWM and a buck converter to generate an amplitude modulated power supply signal having a plurality of quantized voltage levels. The remaining N?K bits of each N-bit words may be used to dither the input drive to the PMW, to produce an error signal at the output of the modulator representing quantization errors caused by only applying the K MSBs to the PWM. The correction circuit compares the error signal to a signal formed form all N bits of the N-bit words in reducing the quantization errors.

Abstract: A power management device providing a power amplifier with power supply voltage is provided. The power management unit includes a parallel-hybrid amplitude modulator apparatus having a linear part configured to track frequency components of an input signal above a determined threshold frequency and a switching part arranged in parallel with the linear part and configured to track frequency components of the input signal below the determined threshold frequency. Additionally, the power management unit includes a current sensing and controlling part configured to determine the level of a direct current component at an output of the linear part and control the switching part to produce an output signal compensating for the direct current component at the output of the linear part to decrease the absolute level of the direct current at the output of the linear part.

Abstract: There is provided a small-size, low-power-consumption intermittent operation circuit capable of obtaining an output waveform having a rapid rise and fall. The intermittent operation circuit includes an active circuit (106), a first control signal generation circuit (101) for generating a first control signal (S1) for controlling the operation start and the operation end of the active circuit (106), a second control signal generation circuit (102) for generating a second control signal (S2) causing the active circuit (106) to perform ringing vibration and controlling the frequency and the amplitude value of the ringing vibration, and a timing adjusting circuit (103) for adjusting the input timing of the first and the second control signal (S1, S2) into the active circuit (106) so that the ringing vibration and the safety vibration are outputted continuously from the active circuit (106).

Abstract: A modulation system includes an amplitude modulation path and a phase modulation path coupled to the amplitude modulation path. One of the amplitude modulation path and the phase modulation path receive a reduced current such that the reduced current reduces power consumption by the system. Preferably, the amplitude modulation path receives the reduced current. The amplitude modulation path has a first set of components and a second set of components. The first set of components consumes less power by using slower operation. The second set of components consumes less power by effectively not operating, or being turned off.

Abstract: In one exemplary embodiment of the invention, an outphasing modulator may include at least a multiplier to multiply an amplitude modulation signal by a phase modulated carrier signal to generate a modulated signal. The outphasing modulator may also include a phase splitter to phase split the modulated signal to generate phase shifted modulated signals. The outphasing modulator may also include a sum-difference combiner to produce outphased modulated signals from the phase shifted modulated signals.

Abstract: 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 sources, a pair of first input transistors, a pair of second input transistors, and a current source controller, where M is an integer greater than 3. The load unit is electrically connected to an output terminal, and the first and second current sources respectively supply a first amount of current and a second amount of current to the load unit. The pair of first input transistors electrically connects the first current source and the load unit in response to a first bit signal, and the pair of the second input transistors electrically connects the second current source and the load unit in response to a second bit signal. The current source controller activates or deactivates one of the first and second current sources in response to the first and second bit signals.

Abstract: A polar modulator contains a phase locked loop which is designed to emit a radio-frequency signal at one frequency to one output, with the frequency being derived from the reference signal and from a phase modulation signal at a control input of the phase locked loop. The modulator additionally has a second signal input for supplying an amplitude modulation signal. The second signal input is connected to a control input of a pulse width modulator, one of whose signal inputs is coupled to the output of the phase locked loop. The pulse width modulator is designed to vary the duty ratio of a signal which is applied to the signal input, with this variation being adjustable via a regulation signal at the control input. A filter can be connected downstream from the output of the pulse width modulator and suppresses higher harmonic components in a signal which can be tapped off at the output of the pulse width modulator.

Abstract: A method is performed for influencing the signal shape of an output signal of an RF power resonance amplifier and an RF excitation arrangement including an RF power resonance amplifier. A basic signal of a basic frequency is amplified and modulated with a modulation signal, and an output oscillating circuit of the RF power resonance amplifier is tuned to a frequency in the range of the basic frequency, and is excited with the basic signal during normal operation. At times that are or can be predetermined, the output oscillating circuit is driven with a driving signal that differs from the basic signal, for a time period that is or can be predetermined. This reduces the dying down time of the output oscillating circuit and increases the steepness of the output signal edges.

Abstract: A method for reducing out-of-band emission in an AM transmitter for digital transmission includes generating, from a digital modulation signal, an amplitude signal and a phase-modulated radio frequency signal configured to control the AM transmitter. A digital modulation process is used in which a hole is formed around a 0/0 point so that a zero crossing is avoided by a substantial margin in a vector diagram representation. Thereby a respective bandwidth of the amplitude signal and the phase-modulated radio frequency signal is limited so that the out-of-band emission decreases as a function of a shoulder distance achievable by the AM transmitter at a rate where a spectrum mask is not exceeded.

Abstract: Various embodiments of a direct digital amplitude modulator (DDAM) for modulating radio frequency (RF) or intermediate frequency (IF) or baseband signal with the invented interpolation technique are disclosed. The interpolation technique greatly reduces the amplitudes of alias signals without using an analog filter. The embodiments therefore are significant for various communication transmitters to achieve simple structure, good linearity and high power efficiency.

Abstract: A synchronized controlled oscillation modulator (SCOM), comprising at least one, Controlled Oscillation Modulator (5), and synchronizing means (1, 6) connected to said COM modulator. The modulator can comprise several COM modulators, and the synchronizing means can be arranged between the COM systems, so that the oscillation modulator signal is used as synchronization signal. The invention provides significant advantages in performance, topological simplification, improved robustness, stability and efficiency compared to prior art.

Abstract: 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 signals that are 90 degrees out of phase with each other. The controller generates modulation control signals based on information that is to be transmitted. The variable current sources each generate a variable amplitude current signal based on a different one of the modulation control signals. Each of the transistor circuits amplify a different one of the quadrature component signals with a variable amplification based on the variable amplitude current signal from a different one of the variable current sources to generate an amplitude adjusted quadrature component signal. The combiner combines the amplitude adjusted quadrature component signals from each of the transistor circuits to generate a phase-modulated RF carrier output signal.

Abstract: In a contactless IC card system, a modulating circuit manufactured in an IC form is operable at a high power efficiency. The demodulating apparatus is configured to include: first signal output means for outputting a first output signal having a predetermined phase with respect to that of an input signal, a second signal output means for outputting a second output signal having a predetermined phase with respect to that of the input signal, gate means for gating at least the second output signal, calculation means for adding, or subtracting the first output signal and the second output signal; and control means for controlling the operation of the gate means in response to a logic level of input data.

Abstract: In an AM system directed to commercial broadcasting, a pure unmodulated (CW) carrier signal and two sideband signals are generated and processed separately as three independent signals that are summed as output of a final linear mixer. The sideband signals are derived independently utilizing audio spectrum-sharing based on complementary comb filtering, quadrature phase-shifting at both audio and carrier sideband frequencies, and exclusive alternate toggling at a designated switching rate between the two sidebands so that at any instant in time only one of the two sidebands is present along with the continuous carrier. The overall performance provides the capability of advantageous modulation beyond the conventional 100% modulation limit.

Abstract: In-flight entertainment systems provide entertainment for passengers on commercial airline flights. Presently, usually on longer flights, video entertainment is commonly available on in-flight passenger entertainment systems. In-flight entertainment systems can display video on a variety of display monitors ranging from a conventional CRT display to a more modern Liquid Crystal Display (LCD). Generally most displays are connected to the aircraft electronic system via a ARINC 722 connector. The ARINC 722 connector commonly provides an electrical interface between the aircraft and the video system, whether the video system is a CRT or LCD type monitor. With the increasing use of LCD monitors there is a greater need for the ability of the display monitor to be able to report its status. The need for status reporting is increased because the LCD monitors are often greater in number than the prior art CRT monitors and because malfunctions are less obvious.

Abstract: In a communication arrangement (1) provided for transmitting data (DA) to a transponder (2) which arrangement includes a data source (5) for delivering data (DA) and includes a carrier signal generator (6) for generating a carrier signal (CS) and includes modulation means (7) to which can be applied the data (DA) and the carrier signal (CS) and which modulation means are provided for modulating a carrier signal (CS) in accordance with the data (DA) and for delivering a modulated carrier signal (CSM) to transmitting means (8) having an input resistance (9), the modulation means (7) have a changeable output resistance (10) which forms a resistance network together with the input resistance (9) of the transmitting means (8), and resistance change means (25) for changing the output resistance (10) in accordance with the data (DA).

Abstract: A non-radiative dielectric (NRD) waveguide modulator is provided having a waveguide type hybrid coupler, in which by forming a waveguide type 180° hybrid coupler and waveguide as a single body, the structure is simplified and manufacturing processes are reduced. The NRD waveguide modulator includes a conducting housing having a lower conducting plate and an upper conducting plate; a hybrid coupler which is processed in the form of conduit lines inside the conducting housing and includes a ring portion and a plurality of waveguides extended from the ring portion in the radial direction, in modulator, and a termination which is connected to an isolation port that is an end of any one waveguide of the hybrid coupler and terminates a signal reflected by the modulator by consuming the signal internally.

Abstract: A transmitter system is provided. In one embodiment, the transmitter system includes a data modulation unit, which generates a stream of data that is synchronized with a master clock. The transmitter system additionally includes a transmitter that transmits the stream of synchronized data by way of an attached antenna. In another embodiment the transmitter system includes a Medium Access Control (MAC) layer that includes a clock synchronization device, a frequency divider, a slot allocation unit, and a multiplexer/demultiplexer. This Abstract is provided for the sole purpose of complying with the Abstract requirement rules that allow a reader to quickly ascertain the subject matter of the disclosure contained herein. This Abstract is submitted with the explicit understanding that it will not be used to interpret or to limit the scope or the meaning of the claims.

Abstract: A method and apparatus for producing a modulation scheme usable in conjunction with information transmission and reception via waveforms, such as electromagnetic waves. The modulation scheme is usable for such purposes as resolving range ambiguities and overcoming fading and interference problems via use of offset signals that vary in frequency over time (e.g., chirp signals), which spread the signal over a larger bandwidth. The method includes coding a symbol signal onto a split data stream containing a reference signal (e.g., a chirp), to which a time delay has been applied, then recombining the split streams to produce a composite waveform. The method can also include demodulating a composite received waveform by applying a reference signal to the waveform and then band pass filtering the waveform into discrete symbol data. Apparatus and systems are also provided for performing the method.

Abstract: The operating method is based on the simultaneous application of FM and AM, and is distinguished by passing through three operating states, specifically a warm-up phase, an impressing phase and the continuous operation. In the warm-up phase, the f002_hor is selected as fundamental frequency of the AM, or an AM is dispensed with. The impressing phase is distinguished by a temporally changing AM deviating from the conditions of the continuous operation and having an AM degree different from zero. In the continuous operation, constant conditions of the AM in the case of which the f002_hor is reached as fundamental frequency of the AM, and the AM degree is at 20 to 25% are characteristic.

Abstract: A transceiver and transmitter are shown. A baseband processor receives a signal for transmission. It converts the signal into amplitude and phase polar components. Each component is then processed—the phase component through a wideband phase modulator and the amplitude component through a wideband amplitude modulator, and the components are then recombined for further processing or transmission.

Abstract: For use in a tire pressure monitoring system, an amplitude modulation (AM) radio frequency (RF) oscillator includes a modulator and a generator. The modulator may be configured to generate a modulation signal in response to a data input signal. The generator may be configured to generate an AM output signal having an RF carrier frequency and an envelope, wherein the envelope is amplitude modulated by the modulation signal and the generator includes a frequency determining device.

Abstract: In a contactless IC card system, a modulating circuit manufactured in an IC form is operable at a high power efficiency. The demodulating apparatus is configured to include: first signal output means for outputting a first output signal having a predetermined phase with respect to that of an input signal, a second signal output means for outputting a second output signal having a predetermined phase with respect to that of the input signal, gate means for gating at least the second output signal, calculation means for adding, or subtracting the first output signal and the second output signal; and control means for controlling the operation of the gate means in response to a logic level of input data.

Abstract: To address the need for a power modulator that can efficiently operate within a wideband, high-speed communication system, a method and apparatus for power modulation is provided herein. In accordance with the preferred embodiment of the present invention an envelope reference signal is filtered in such a way that the bandwidth is reduced while keeping the instantaneous level of the filtered signal is greater than the unfiltered envelope level. Because the bandwidth of the envelope signal is reduced, efficient operation of the switching modulator can be achieved within wideband, high-speed communication systems.

Abstract: A base band signal is frequency limited by a band limiting circuit 1. The waveform of this output signal rises and falls smoothly against a time axis. A driving circuit 2 functions as a buffer amplifier with voltage gain of 1 between the band limiting circuit 1 and ASK modulation circuit 3, and the output voltage wave is equal to the output waveform of the band limiting circuit 1. The ASK modulation circuit 3 turns on/off a field effect transistor 61 by the output signal voltage from the driving circuit 2, thereby discontinuing the carrier of the microwave band to be externally entered and performing ASK modulation (binary ASK), and provides a desired ASK modulated waveform as a result.

Abstract: Quadrature modulators include a quadrature splitter and a pair of Gilbert Multiplier Cells coupled to the quadrature splitter, each of which is biased in Class-B. The quiescent current bias in the Gilbert Multiplier Cells may be substantially zero. Each of the Gilbert Multiplier Cells may include a pair of cross-coupled, emitter-coupled transistor pairs transistor pairs and a driver circuit that is coupled to at least one of the emitter-coupled transistor pairs and that is biased in Class-B. The driver circuit may include at least one current mirror circuit that is coupled to at least one of the emitter-coupled transistor pairs. The driver circuit also may include at least one current source that selectively applies current to at least one of the emitter-coupled transistor pairs, more specifically by selectively applying current to the at least one current mirror circuit.

Abstract: A branched power amplifier circuit includes two or more amplifier segments or branches, each with a corresponding lossy modulator. The branched power amplifier may be dynamically resized by enabling different ones of its branches, to deliver peak efficiency at a number of different amplifier output power levels. Each amplifier branch operates in a saturated mode and selectively amplifies an RF input signal. The lossy modulators provide either supply voltage or supply current modulation to corresponding amplifier branches, thus imparting highly linear amplitude modulation to the overall output signal generated by branched power amplifier, despite its saturated mode operation. The branched power amplifier circuit may be configured such that particular combinations of segments have peak efficiencies matched to the needs of one or more air interface standards used in wireless mobile communication systems.

Abstract: To address the need for a power modulator that can efficiently operate within a wideband, high-speed communication system, a method and apparatus for power modulation is provided herein. In accordance with the preferred embodiment of the present invention an envelope reference signal is filtered in such a way that the bandwidth is reduced while keeping the instantaneous level of the filtered signal is greater than the unfiltered envelope level. Because the bandwidth of the envelope signal is reduced, efficient operation of the switching modulator can be achieved within wideband, high-speed communication systems.

Abstract: An amplitude modulated source signal (102) is received, where this signal has a source frequency bandwidth and a source envelope. A dummy envelope is computed that would yield a constant if the dummy envelope and source envelope were to be combined. An amplitude modulated dummy signal (105) is generated, where this dummy signal exhibits the computed, dummy signal envelope and has a prescribed frequency bandwidth different than the source frequency bandwidth. The source and dummy signals are added to form a combined signal (113), which is directed to an input (114a) of a nonlinear circuit (114), that is, one that exhibits amplitude dependent nonlinearity. Signals of the dummy frequency bandwidth and any intermodulation products are filtered from the output, thereby providing a linearized output (118) corresponding to the original, source signal.

Abstract: A circuit, method, and network are disclosed herein to implement a voltage-controlled LC oscillator. The oscillator is configured having an LC tank circuit which is modulated by an in-phase modulating voltage. The modulating voltage can have a phase angle and amplitude that is controlled. Depending on the values of those control signals, the oscillating voltage will either increase or decrease current within the LC tank circuit and, thereby, increase or decrease the oscillating voltage respectively. Any number of phases can be connected together to produce signals of dissimilar phase angles. Preferably, those signals have phase angles of 0°, 180°, or even fractions thereof if an external circuitry is applied to the oscillation network.

Abstract: A modulation circuit includes a band restriction filter 2, an attenuator 3, a modulator 4, a reference voltage generator 8, a comparing reference voltage generator 9, a voltage comparator 10 and an attenuator controller 7. The band restriction filter 2 receives modulation data. The attenuator 3 is connected to the band restriction filter 2 for adjusting its attenuation in response to an attenuator control signal. The reference voltage generator 8 is connected to the attenuator 3 for providing a reference voltage independent of a temperature and a power supply voltage to the attenuator. The comparing reference voltage generator 9 is connected to the reference voltage generator 8 for providing a comparing reference voltage independent of the temperature and the power supply voltage. The modulator 4 is connected to the attenuator 3.

Abstract: An inexpensive method and means for generating high power envelope-modulated radio frequency signals is disclosed. Embodiments provide EER amplification and separate modulation of information encoded as phase angle and as amplitude. An envelope modulated signal generation apparatus comprising a source of carrier signal, a source of a binary data stream, a pulse deletion logic and a current switch is disclosed.