| Document |
Document Title |
|
WO/1998/034339A1 |
A digital compensation filtering technique is provided that enables indirect phase locked loop modulation with a digital modulation data stream having a bandwidth that exceeds, perhaps by an order of magnitude, the bandwidth characterist...
|
|
WO/1998/032220A1 |
The object of the invention is to stabilize the frequency of a YIG-oscillator connected to a phase-locking loop. According to the invention, this object is achieved in that an active loop filter with a low-noise operation amplifier is co...
|
|
WO/1998/028852A2 |
A system (10) and method are provided in which a phase modulation generator (12) is used to modulate the output signal of a DDS (18) with a modulation index, h/N. The phase-modulated DDS output drives a PLL (26), which is an upconversion...
|
|
WO/1998/023068A1 |
A nonlinear distortion compensator which can compensate for the nonlinear distortion occurring in the amplifier of a transmission system without using a storage table and has a large distortion reduction effect, by computing nonlinear di...
|
|
WO/1998/020607A1 |
A frequency modulator (50, 150) for modulating a carrier signal according to a modulation data signal to provide a modulated output signal (RFout), comprises a reference signal generator (54, 154) coupled to receive the modulation data s...
|
|
WO/1998/017014A1 |
The invention concerns a data-transmission circuit with a station (1) and a response circuit (2), the station comprising a primary coil (4) with a signal generator (3) for generating a magnetic alternating field at a carrier frequency, a...
|
|
WO/1998/013943A1 |
Unwanted transmitter modulation which would otherwise have an undesirable impact at a radio receiving the transmitted signal is detected and cancelled. The radio transmitter includes a phase-locked loop that receives an input signal and ...
|
|
WO/1998/009371A1 |
With the help of a program-controlled processor (PR), digital compensation values (gk1, gk2) corresponding to at least one stored compensation value (KW1, KW2) are formed and overlaid onto the corresponding modulator signal (as, ds) to b...
|
|
WO/1998/008299A1 |
A transmitter controller (50) comprises a synthesiser (52), a voltage controlled oscillator (54), a signal processor (56), a crystal (58) and a variable capacitor (60). Data to be transmitted enters the system at 62. The data is scale da...
|
|
WO/1998/008298A1 |
A voltage-to-frequency converter having an analog-to-digital converter (22), based on analog components, for converting samples of an analog signal (Vin) into corresponding digital words and a digital-to-frequency (26), based on digital ...
|
|
WO/1997/047090A1 |
According to the exemplary embodiments, a voltage or current-controlled oscillator is controlled in frequency by the signal (i.e., voltage or current) from a microphone. The frequency modulated signal is applied to a direct digital discr...
|
|
WO/1997/038490A1 |
A method and apparatus for wirelessly transmitting (10) and receiving digital information using an analog carrier (24, 26) where the required bandwidth is limited to approximately the frequency of the analog carrier signal. The method is...
|
|
WO/1997/035412A1 |
An apparatus and a method for routing digitized radio frequency (RF) signals (140-143) to a plurality of paths are described herein. In accordance with a first preferred embodiment, the apparatus includes a digital converter/modulator (D...
|
|
WO/1997/030521A1 |
A linear transmitter (101) using predistortion includes a modulator (103), a predistorter (107), a digital quadrature modulator (111), an upconverter (113), a power amplifier (115), and an antenna (117). In addition, the transmitter (101...
|
|
WO/1997/026704A1 |
A switchable voltage-controlled oscillator (14) includes at least one signal input node receiving reference and modulation signal inputs and a signal output node. Resonant circuitry (52, 54) establishing the operating frequency range of ...
|
|
WO/1997/025773A1 |
Described is a method and device for modulating the frequency of a high-frequency signal, the signal being generated by an oscillator which is controlled by comparing the actual frequency signal with an adjustable reference frequency sig...
|
|
WO/1997/023032A1 |
Methods and systems for calibrating transceivers are described. Analog transceiver components create errors, such as gain and offset errors in a receiver or a transmitter portion, which are compensated by adjusting digital signal process...
|
|
WO/1997/023051A2 |
To realize a radio apparatus which can accurately compensate a linear characteristic of a power amplifying stage through automatically adjusting a time lag between an offset voltage of a transmitting system and that of a negative feedbac...
|
|
WO/1997/019521A1 |
A method for removing signal residues outside the working frequency band of radio signal transceivers using a quadrature signal modulator-demodulator consisting of two quadrature channels (3, 4), wherein the low-frequency transmit signal...
|
|
WO/1997/018624A1 |
An FM modulator (1) includes two phase shifting circuits (110C and 30C) and a capacitor microphone (14-1) is provided in the circuit (110C). The FM modulator (1) oscillates at the frequency at which the sum of the amounts of phase shift ...
|
|
WO/1997/018625A1 |
An FM modulator (1) includes two phase shifting circuits (10C and 130C) and an FET (35) is provided in a CR circuit in the circuit (130C). The FM modulator (1) oscillates at the frequency at which the sum of the amounts of phase shift by...
|
|
WO/1997/015980A1 |
A transmitter comprising at least first and second phase related signal paths (I, Q), having respective frequency up-converting means (28, 30, 32, 34), means (35) for combining the output of the respective frequency up-converting means a...
|
|
WO/1997/009777A2 |
In order to improve the linearity of the frequency modulation, the frequency-modulated signal (fT(t)) and the same signal delayed by a time 'tau'(fT(t-'tau')) via a surface wave component (OFW) is applied to the inputs of a mixer (M). Th...
|
|
WO/1997/006607A1 |
Amplitude and phase errors betweens branches I and Q of a transceiver utilizing phase quadrature modulation are corrected by preventing propagation of a nominal-frequency signal from a digital part (10) through a loop part (44) and a rec...
|
|
WO/1997/005704A1 |
A receiver (100), transmitter (200) and transceiver (400) in accordance with the present invention overcome the disadvantages of applying adaptive antenna array technology to multi-channel communication systems. Multi-channel radio frequ...
|
|
WO/1996/037948A1 |
The invention includes apparatus for processing an input signal to generate an output signal. The processing arrangement comprises first and second feedback loops for generating, from said input signal, respective output signal component...
|
|
WO/1996/033553A1 |
A dual port frequency modulator and method for eliminating the undesired effects caused by high port/low port phase differences in a standard dual port frequency modulator. The frequency modulator includes an inverse filter stage coupled...
|
|
WO/1996/031943A2 |
In a receiver two sigma delta modulators (13, 19) are used to convert a pair of analog quatradure signals into digital quadrature signals. In such sigma delta modulators the quantisation noise is shifted into a frequency region in which ...
|
|
WO/1996/031942A1 |
A multiple access digital up converter/modulator includes selectors (1606, 1608) having inputs (1602, 1604) and outputs coupled to first and second interpolating filters (1610, 1626). The output of the first interpolating filter is selec...
|
|
WO/1996/030996A1 |
Circuit for modulating a crystal oscillator, having an overtone crystal, wherein a self-inductance (L1) and a parallel circuit comprising a capacitor (C3) and a diode (D2) in series with a predetermined reference voltage (Uref) are conne...
|
|
WO/1996/027943A1 |
A clock apparatus (420) reduces electromagnetic emissions from a microprocessor (102). The apparatus modulates the phase locked loop (410) of the microprocessor's internal clock so that it produces a frequency modulated ouput. The appara...
|
|
WO1996025809A1 |
In a quantization noise reduction circuit (200), a feedback signal (W) is added to an input signal (X) to the quantization circuit to reduce quantization noise. The feedback signal is generated as a filtered difference between a sample o...
|
|
WO/1996/023366A1 |
In the method and circuit for creating a modulated signal, one input signal of a phase comparator (509) of a phase-locked frequency synthesizer is an offset frequency (f2), which is created from an adjustable oscillator's (511) output si...
|
|
WO/1996/023232A1 |
A low-cost local oscillator of a spectrum analyzer, in which linearity is corrected during the frequency scanning of a voltage-controlled oscillator. To accomplish this object, a linearity correction circuit (78) for giving a definite gr...
|
|
WO/1996/021288A1 |
A multi-channel digital transceiver (400) receives uplink radio frequency signals and converts these signals to digital intermediate frequency signals. Digital signal processing, including a digital converter module (426), is employed to...
|
|
WO/1996/021291A1 |
A digital signal transmission system is provided which minimizes the analog AM signal envelope distortion caused by multiple digitally modulated carriers in the same band as the analog AM signal. The present transmission system includes ...
|
|
WO/1996/021279A2 |
The invention relates to a circuit for frequency synthesis, comprising: a digital controlled oscillator, comprising (a) a clock generator; an accumulator circuit to which the signal from the clock generator is fed; and a control digit fe...
|
|
WO/1996/018250A1 |
A method (100), a device (300), and a radio (500) are described for compensating for modulator frequency drift while allowing for data transmission in a half-duplex frequency modulated communication system. An adjustment is made to a pre...
|
|
WO/1996/018238A1 |
The device according to the invention is provided on a receiver side (E) with at least one series circuit comprising a clock-pulsed band-pass filter (GT), a Schmitt trigger (ST) and a digital demodulator (DDM); and on an emitter side (S)...
|
|
WO/1996/017287A1 |
A direct digital synthesizer (DDS) for generating a waveform generates a sequence of n-bit phase signals representing phase of the waveform, wherein n is an integer greater than zero. Each n-bit phase signal comprises a phase estimate si...
|
|
WO/1996/015585A1 |
An IQ modulator in which digital I (155) and Q (153) signals, which are quadrature representations of a modulating function, are connected into corresponding analogue I (165) and Q (163) signals using a first (156, 135) and second (154, ...
|
|
WO/1996/015584A1 |
An improved apparatus for digitally synthesizing musical sounds. The apparatus according to the invention includes a phase angle generator (28), a quarterwave sine logic element (30), a wave constructor component (34) and a modulation lo...
|
|
WO/1996/014590A1 |
In order to generate a linear frequency ramp when identifying passive mobile SAW-transponders, a base band signal with a linearly rising frequency is generated by direct digital synthesis (1). This signal is then modulated on a carrier f...
|
|
WO/1996/013895A1 |
A frequency synthesizer (10) having a digital-to-analog converter (DAC) (40) and a feedback system which detects the deviation of a frequency modulated signal and aligns the detected deviation. DAC (40) provides a presteering stimulus fo...
|
|
WO/1996/011526A1 |
A digital data demodulator/decoder (30) for either a quadrature amplitude (QAM) or vestigial sideband (VSB) modulated signal includes a quadrature detector (32, 33) feeding through digital filters (38, 39) to a decoder (50) which switche...
|
|
WO/1996/009690A1 |
The invention concerns mixers which are used for frequency conversion in high-frequency communication apparatus. The object of the invention is to compensate useful signals which are picked up undesirably at the mixer converter inputs by...
|
|
WO/1996/008865A2 |
A quadrature modulator for generation of complex modulated signals includes a unique pair of balanced, low-pass filters which, through a switching arrangement for switching into and out of the circuit distributed RC line sections and cor...
|
|
WO/1996/008079A1 |
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 modules, conventionally disposed in a diod...
|
|
WO/1996/007242A1 |
A stacked double balanced mixer (220) includes a double balanced mixer (320) and a first cross coupled differential mixer (330). The double balanced mixer (320) includes two input transistors (321, 322) and four cross coupled output tran...
|
|
WO/1995/034126A1 |
The method and apparatus involve receiving (118) one's own transmission with a suitable modulation assessment receiver (119-125) and determining (125) the modulation error relative to the theoretically perfect modulation transmission exp...
|
