Modulator
This invention provides a modulation device which is to modulate base frequency signal, which includes phase-splitter, low pass filter and adjustor. The phase-splitter produces a polarit...
Frequency converter and tuner A frequency changer (3, 4) is provided for a radio frequency tuner (1-7). The frequency changer comprises a mixer (3) comprising a plurality of mixing stages (10a, 11a; 10b, 11b; 10c, 11c...
Analogue multiplier
An analogue multiplier circuit has an input coefficient voltage dependent adjustment of its frequency response. The multiplier contains a multiplier cell (MC) with an RF input (Vin , Vin...
Distortion adaptive high-capacity scatter communication modem The utility model discloses a distortion adaptive high-capacity scatter communication modem. It relates to a modem device with stronger anti inter-symbol interference ability in the commu...
Frequency modulation device
A frequency modulation apparatus 100 has a synthesizer 101 , a differentiator 102 that differentiates phase modulation data and generates differential phase modulation data, an adder 103...
14
200580012344
Programmable radio transceiver A fully integrated, programmable mixed-signal radio transceiver comprising a radio frequency integrated circuit (RFIC) which is frequency and protocol agnostic with digital inputs and out...
15
200580006038
PLL circuit [PROBLEMS] To reduce EMI noise by use of a simple arrangement. [MEANS FOR SOLVING PROBLEMS] A PLL circuit comprising a control part for switching, at predetermined timings, the validity/i...
16
200580006425
Transmitter apparatus and wireless communication apparatus A transmitter apparatus capable of performing a high-efficiency polar coordinate modulation, while maintaining a good distortion characteristic. In the case of causing a large power ampli...
17
200510007839
Transmission circuit
A transmission circuit capable of transmitting a modulated wave signal using polar modulation in a broad band and with low power consumption is provided. The transmission circuit generat...
18
200580003550
Adjusting circuit The invention relates to an adjusting circuit for adjusting an amplitude of a radio frequency signal. The adjusting circuit comprises a plurality of terminals for input and output, a matc...
Outphasing modulator
Briefly, an apparatus having an outphasing modulator that may provide at least first and second outphased signals to a power amplifier. The outphasing modulator may control amplitude of ...
21
200480037460
Radio device A mobile device is used for receiving supplementary information transmitted with a radio station signal, said mobile device comprising: means for scanning a spectrum of frequencies; means...
Modulator and correction method thereof It is possible to maintain conformance of frequency characteristic and prevent lowering of modulation accuracy in a wide band modulator using a PLL synthesizer even when manufacturing irr...
Apparatus and method for wideband signal processing An apparatus for electromagnetic processing comprises a modulator for generating one or more elements representative of an input signal; a divider controlled by the one or more elements a...
Amplitude-modulation antenna of noise reduced
An AM radio antenna circuit having a ferrite bar loop antenna comprises a resonating structure forming a balanced antenna circuit, a varactor diode tuning structure presenting a controll...
33
03820346
Method of modulation gain calibration and system thereof
A wideband impedance attenuator includes a phase-locked loop filter, a voltage-controlled oscillator connected to the phase-locked loop filter during transmit, and an impedance circuit c...
34
03819269
Voltage control oscillator having modulation function
There is provided a VCO having a modulation function capable of easily constituting a correction circuit which can obtain a predetermined modulation degree even when element irregulariti...
Method and apparatus of compensating imbalance of a modulator Briefly, a method and apparatus to compensate an imbalance of a modulator by providing calibration parameters to a calibration network. The modulator may receive a pair of predetermined s...
37
03805987
Transmitter arrangement for frequency modulation A transmission arrangement includes a step-up frequency mixer that converts a modulation signal to a transmission frequency. The step-up frequency mixer is arranged within a phase locked ...
38
03120547
Frequency modulator, frequency modulation method and radio line A voltage controlled oscillator (1), a variable frequency divider (2), a phase comparator (3), and a loop filter (4) form a Phase Locked Loop (PLL). A sigma-delta modulator 5 sigma-delta ...
39
03812886
Linearity improvement of gilbert mixers
Method and system are disclosed for providing an improved linearity Gilbert mixer. The Gilbert mixer of the ivention includes a convenional mixer core coupled to a high linearity multius...
40
03804330
DSP-based variable aperture code generation technique Variable Aperture Coded (VAC) signals for VAC modulation are advantageously generated by a digital signal processor (12) that yields a VAC signal having a single narrow in the positive fr...
Transceiver using a harmonic rejection mixer A wireless transceiver includes a transmitter having a harmonic rejection mixer and an RF output phase-locked loop in a two step up-conversion architecture, and a direct conversion receiv...
High data rate wireless communication system A high data rate communication system operating at frequencies greater than 70 MHz and at data rates of about 1.25 Gbps or greater. Preferred embodiments include modulators with a resonan...
46
03803802
Single point modulator having a PLL circuit The invention relates to a point modulator (1) comprising a PLL circuit (2). A programmable frequency distributor (7) is arranged in the feedback branch of the PLL circuit (2), the contro...
Alternate timing signal for a vestigial sideband modulator
A remodulator timing signal (35) is generated by a phase locked loop (33) which is coupled to a broadcast vestigial sideband signal (5). Within the signal (5) is highly accurate timing d...
49
02825236
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 t...
Stereo synthetic coder (MPX) for FM transmission A stereo multiplex encoder (MPX) for FM transmission with a digital signal processor utilizes residual sideband modulation in stereo transmission instead of the conventional double sideba...
Radio pulse communications systems
Frequency modulation switching apparatus for rapidly increasing and decreasing the frequency within radio-frequency pulses of radio wave pulse trains transmitted by an antenna having ser...
55
02111821
Feedback modulating circuit
A feedback modulation circuit for increasing the card reading distance by 1.5-2 times is composed of a resonant circuit consisting of resonant capacitor and resonant antenna for obtainin...
System for controlling class D amplifier
Communications systems, and particularly portable personal communications systems, such as portable phones, are becoming increasingly digital. The tendency towards digital systems has co...
Power oscillator for control of waveshape and amplitude
An RF power oscillator for contactless card antennas shapes a carrier signal at the operating frequency utilizing a delay circuit having a number of taps for delaying the carrier signal ...
System and method of RF power amplification
A radio frequency power amplifier circuit provides linear amplitude modulation of a radio frequency output signal while operating in a saturated amplification mode. The power amplifier c...
Quadrature generator with image reject mixer
In an exemplary application, an apparatus according to a disclosed embodiment receives a radio frequency signal and outputs an intermediate frequency signal. Rejection of image component...
68
01818390
Direct digital amplitude modulator
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 t...
69
01813798
Frequency modulator using a waveform generator A Multi-mode Loop Frequency modulator (10) for modulating a carrier signal according to various modulation pulse shapings and data signal to provide a modulated output signal (VCOout), co...
Transmitter and method for producing transmitting signals The present invention can improve a conventional transmitter for generating a transmission signal and its method by reducing expenses needed to filter the transmission signal because of t...
72
01117821
Transmitter and method for producing transmission signal The invention relates to a transmitter and a method of generating a transmission signal, which transmitter includes a modulation device (110) for generating two uncompensated transmission...
Method and device for calibrating FM PLL In accordance with the present invention, a frequency modulating phase-locked-loop (FMPLL) architecture is implemented. The frequency of the FMPLL is controlled using a current controlled...
75
00816668
Transmitting device The invention relates to a transmitting device in which a modulation signal is produced according to data to be transmitted, a transmission frequency generation device (9) being controlle...
76
00817767
Dielectric resonator oscillator and voice control device The invention relates to a dielectric resonator oscillator, comprising a dielectric resonator (4) which is contained in a resonant cavity (2) for generating a signal that oscillates at a ...
77
00801654
Fractional-N frequency synthesiser A fractional-N frequency synthesizer for use in a transmitter for transmitting TDMA signals, comprises a fourth order sigma-delta modulator (16) having an input for digitized signals, a F...
78
00124079
Phase-locked loop frequency synthesizer A phase-locked loop frequency synthesizer includes circuitry which determines the real gain of a voltage-controlled oscillator from at least one measurement parameter and delivers a signa...
Single sideband mixer The invention relates to a single sideband mixer for radio frequency signals which can be integrated on a uniform semiconductor substrate in a space-saving manner. The inventive single si...
Method for modulating the amplitude of an antenna signal The invention relates to a method for modulating the amplitude of an antenna signal (Sa) applied to an inductive-type antenna circuit (10) by means of a control circuit (2) comprising bin...
Method and apparatus for modulating digital data The modulator includes an oscillator generating signals, each having a different phase, and a selector receiving digital data. When the digital data received by the selector changes logic...
Power 1-Q modulation systems and methods Power IQ modulations systems and methods include first and second power amplifiers, each including a signal input, a supply input and a power input. The first and second power amplifiers ...
87
00800924
Quadrature modulator with 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, r...
Demodulator circuits A demodulator circuit for demodulating a frequency modulated input signal comprises filter means (12) for receiving an incoming input signal and for providing a filtered output signal, de...
93
99104269
Load regulation technique and its communication method
The present invention relates to a carrier modulation technique in radio communication, which features use of non-polar conversion mode to modulate amplitude, omitting the current direct...
94
98810942
Qam modulation using direct digital synthesis and upconversion A transmitter subsystem (100 and 200) is disclosed whereby the output frequency spectrum of a DDS device (202), for use in the transmitter subsystem, is frequency multiplied to achieve gr...
95
98123005
Frequency converter circuit of tuner for cable modem A local oscillation circuit in a frequency converter circuit includes a resonant circuit, and a differential amplifier circuit connected to the resonant circuit. The differential amplifie...
New-type modem and its power source controlling method
One MCU unit controls the DSP unit and power source controlling unit according to the DTR signal from the serial port of the terminate and the ringing signal from far end. The present in...