Angle Modulation Patents (Class 375/271)
  • Patent number: 7082169
    Abstract: A mirror translation loop upconverter that is capable of upconverting both constant envelope and non-constant envelope modulation formats is disclosed. Embodiments of the invention provide the ability to upconvert a transmit signal that includes only a phase-modulated component, only an amplitude-modulated component, or both a phase-modulated component and an amplitude-modulated component. If the transmit signal includes both a phase-modulated signal component and an amplitude-modulated signal component, the phase-modulated signal component and the amplitude-modulated signal component are supplied to a pair of phase shifters. The phase shifters alter the phase of the phase-modulated signal by an amount related to the amplitude of the amplitude-modulated signal. The phase shifters oppositely alter the phase of the phase-modulated signal, and therefore supply complementary phase versions of the phase-modulated signal.
    Type: Grant
    Filed: July 29, 2002
    Date of Patent: July 25, 2006
    Assignee: Skyworks Solutions, Inc.
    Inventors: Dmitriy Rozenblit, William J. Domino, Morten Damgaard
  • Patent number: 7035344
    Abstract: Ultra Efficient Modulation-Demodulation (modem) and Transmitters-Receivers (transceivers) for high spectral efficient signal generation and processing methods and implementations. Embodiments include Clock Modulated (CM) and Shaped Clocked (SC) transceivers designated as Feher Keying (FK), Feher Quadrature Shift Keying (FQPSK) and Feher Quadrature Modulation (FQAM). In the FK modulator, clock converted and clock shaped signals are processed and generated. These are based on the input data signal patterns.
    Type: Grant
    Filed: December 7, 2000
    Date of Patent: April 25, 2006
    Inventor: Kamilo Feher
  • Patent number: 7027505
    Abstract: A system and method for improving radio communication of frequency or phase modulated transmission and reception. Signal transmission is implemented by suppression of the upper and lower sidebands of a narrowband or very narrowband FM/PM signal from the transmission medium such that transmission is limited to the instantaneous frequency varied about the carrier frequency (center frequency). Suppression may be achieved by adding a bandpass filter between the modulator and the power amplifier of the narrowband FM transmitter. Upon receipt of the suppressed sideband signal, the received signal is converted to a first narrowband IF signal, and then the narrowband or very narrowband frequency deviation IF signal is expanded by frequency multiplication to generate a second wideband or very wideband IF signal. A discriminator may be used to convert the frequency-multiplied signal into a low frequency signal or audio signal for further processing.
    Type: Grant
    Filed: May 4, 2001
    Date of Patent: April 11, 2006
    Inventor: Abdullah A. Al-Eidan
  • Patent number: 7023932
    Abstract: The invention disclosed in this application discloses a method for modulating and demodulating compressed binary information that was derived from a binary information stream composed of a binary data sequence of first and second binary states that was modulated onto a carrier which has a waveform with a continuous sequence of wavelets with similar amplitudes defined by a 360 degree cycle between crossover positions representing a substantially zero energy level in which the carrier has been modulated in accordance with said binary data sequence by grouping said wavelets into wavelet groups containing two or more wavelets, receiving said information stream as a binary data sequence of first and second binary states; grouping said binary data sequence of first and second binary states into binary groups of two or more first and second binary states; correlating one of each said wavelets in said wavelet group with one of each possible binary values of each said binary groups, modulating said carrier in accordan
    Type: Grant
    Filed: January 28, 2004
    Date of Patent: April 4, 2006
    Assignee: XG Technology, LLC
    Inventors: Joseph Bobier, Nadeem Khan
  • Patent number: 7020226
    Abstract: A transmitter (102) generates a first set of data symbols and a first pilot symbol (601) at a first time, and a second set of data symbols and a second pilot symbol (602) at a different, second time. The first (601) and second (602) pilot symbols are each represented by first (701) and second (702) pilot carriers, respectively, located at first (703) and second (704) predetermined sample frequencies, respectively, in a channel bandwidth. For the first pilot symbol (601), the first (701) and second (702) pilot carriers have first and second predetermined values, respectively. For the second pilot symbol (602), the first (701) and second (702) pilot carriers have third and fourth predetermined values, respectively.
    Type: Grant
    Filed: April 4, 2002
    Date of Patent: March 28, 2006
    Assignee: Nortel Networks Limited
    Inventor: William R. Kirkland
  • Patent number: 7003046
    Abstract: A final 15-bit output code word is generated in response to every 8-bit input code word by referring to a set of encoding tables. The encoding tables contain output code words assigned to input code words, and contain state information accompanying each output code word. The state information designates an encoding table among the encoding tables which is used next to generate an output code word immediately following the output code word accompanied with the state information. When given conditions are satisfied, first and second candidate current output code words generated in response to a current input code word by referring to first and second specified ones of the encoding tables. One is selected from the first and second candidate current output code words as a final current output code word in response to DSV calculation results. Auxiliary information is superimposed on a sequence of final output code words.
    Type: Grant
    Filed: November 13, 2001
    Date of Patent: February 21, 2006
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Atsushi Hayami, Takayuki Sugahara
  • Patent number: 6996371
    Abstract: The invention relates to a device for aiding the analysis of signals by using symbols-based digital modulation. The device includes a signal memory for storing a complex digital signal, representative in amplitude and phase of a captured signal, over a chosen duration, as well as a processor for searching for the properties relating to the carrier frequency of the complex signal and to its modulation. According to the invention, the processor includes a projector for calculating the components of the complex signal in a function basis, the function basis being parameterized according to an estimated tempo of the modulation, as well as a calculator, operating on these components so as to determine an estimate relating to a property of the complex signal, from among its elementary pulse shape, the string of symbols of the complex signal and its carrier.
    Type: Grant
    Filed: July 9, 2001
    Date of Patent: February 7, 2006
    Assignee: Thales
    Inventors: Jean-Yves Delabbaye, André Couderette
  • Patent number: 6977965
    Abstract: A receiver includes an I-Q demodulator (135) responsive to the I and Q components carried on a first frequency signal line (132). A demodulator frequency generator (275) generates a demodulating signal to extract the carried I and Q components. A phase adjustment circuit (105) makes the demodulating signal substantially in phase with the first frequency signal. A transition detector (445) generates a state transition signal in response to a change of state of at least one of the I and Q signals. A peak detector (460) generates a peak detected signal in response to occurrence of a peak amplitude of at least one of the I and Q signals. A clock generator (470) adjusts the phase of a symbol clock signal used to decode the I and Q components in response to the state transition signal and peak detected signal.
    Type: Grant
    Filed: October 2, 2002
    Date of Patent: December 20, 2005
    Assignee: Tellabs Operations, Inc.
    Inventors: Luu V. Nguyen, Victor S. Ivashin
  • Patent number: 6968014
    Abstract: A sinusoidal R.F. carrier is modulated for the transmission of digital binary datastreams through the deletion of carrier wavelets. These wavelets are defined between zero crossover positions representing zero energy locations. One or more wavelets are switched out of the carrier at the zero crossing positions to avoid sideband generation occasioned by electromagnetic energy disturbance. Transmissional amplification as well as receptional amplification is carried out with non-resonating amplifier architecture.
    Type: Grant
    Filed: February 23, 2000
    Date of Patent: November 22, 2005
    Assignee: XG Technology, LLC
    Inventor: Joseph A. Bobier
  • Patent number: 6961367
    Abstract: A forward link repeater frequency watermarking (FLRFWM) system and method that enable accurate position location of mobile stations in areas where repeaters are present by watermarking repeated signals with repeater information. A repeater watermarks a forward link signal with a (unique or non-unique) fast frequency modulation waveform watermark every time a signal passes through the repeater. A mobile station detects and/or identifies the fast frequency watermark on the forward link signal to determine repeater information that aids the network position determination entity or mobile station position location system in determining position location using AFLT and/or A-GPS systems. A forward link fast frequency watermarking system described herein achieves minimal impact on FL, AFLT, and GPS performance, good detection, identification and false alarm probabilities, short time-to-detect/identify, and good detection/identification sensitivity.
    Type: Grant
    Filed: March 17, 2003
    Date of Patent: November 1, 2005
    Assignee: QUALCOMM, Incorporated
    Inventors: Emilija Simic, Christopher Patrick
  • Patent number: 6901246
    Abstract: A sinusoidal RF carrier is modulated for the transmission of digital binary data streams through the amplitude suppression of carrier wavelets. These wavelets are defined between zero crossover positions representing zero energy locations. This modulation is accomplished when the carrier is slightly amplitude modulated with a modulation signal that is equal in frequency to the carrier itself and the modulation always begins or ends upon the exact zero voltage crossing point of the RF cycle phase. The modulation is applied as a slight shift of the amplitude of any single cycle, each cycle representing a single bit of data. A single cycle of RF will either represent a “1” or “0” depending upon the amplitude of the cycle, relative to other adjacent cycles in the same carrier.
    Type: Grant
    Filed: July 26, 2001
    Date of Patent: May 31, 2005
    Assignee: XG Technology, LLC
    Inventors: Joseph Bobier, Nadeem Khan
  • Patent number: 6829308
    Abstract: An approach for reliably communicating over a satellite in support of a communication service including, for example, as direct broadcast satellite and data service, is disclosed. An input message is encoded, yielding a structured Low Density Parity Check (LDPC) coded message. The coded message is modulated according to a high order modulation scheme that has a signal constellation representing more than two symbols per signaling point—e.g., 8-PSK (Phase Shift Keying) and 16-QAM (Quadrature Amplitude Modulation). The system includes a transmitter configured to propagate the modulated signal over the satellite. The above approach is particularly applicable to bandwidth constrained communication systems requiring high data rates.
    Type: Grant
    Filed: January 28, 2003
    Date of Patent: December 7, 2004
    Assignee: Hughes Electronics Corporation
    Inventors: Mustafa Eroz, Feng-Wen Sun, Lin-Nan Lee, Dan Fraley
  • Patent number: 6810092
    Abstract: A method and a circuitry for demodulating a digital frequency-modulated signal. After demodulating the digital frequency-modulated signal for generating the signal's amplitude and differential phase value &phgr;, the amplitude of the demodulated signal is compared with a constant at determined sampling times. The phase value of each sampling time is multiplied by a factor, the factor (c) being the product of the amplitude of the determined sampling time and the amplitude of a preceding sampling time, if the amplitude is less than the constant.
    Type: Grant
    Filed: October 11, 2000
    Date of Patent: October 26, 2004
    Assignee: Robert Bosch GmbH
    Inventors: Bjoern Jelonnek, Lothar Vogt
  • Patent number: 6795932
    Abstract: A clock switchover circuit includes a NAND circuit supplied with an output of a first inverter circuit, and a first flip-flop (DFF) supplied with an output of the NAND circuit. Further, the circuit includes a NOR circuit, and a second DFF supplied with an output of the NOR circuit. A second inverter circuit is supplied with an output of the first DFF. A clock signal selection section is supplied with outputs of the second DFF and the second inverter circuit. A third inverter circuit is supplied with an output of the clock signal selection section and produces a clock signal.
    Type: Grant
    Filed: May 14, 2001
    Date of Patent: September 21, 2004
    Assignees: Renesas Technology Corp., Mitsubishi Electric System LSI Design Corporation
    Inventor: Tsuyoshi Ohkawa
  • Publication number: 20040179628
    Abstract: A frequency modulation method, system and computer readable-medium for enabling high speed, reliable and simple digital data modulation, transmission and reception. The system of the present invention includes a Synthetic Harmonic Waveform Generator for generating harmonic waves of the form cos(2&pgr;fdevt) from a digital data bit stream. The system of the present invention uses the generated harmonic waves to create a frequency modulation signal of the form sin(2&pgr;fcarriert±2&pgr;fdevt), which is then transmitted. The present invention also includes a demodulation technique for receiving a signal of the form sin(2&pgr;fcarriert±2&pgr;fdevt), which is used to determine whether a “1” or “0” digital bit has been transmitted.
    Type: Application
    Filed: April 16, 2004
    Publication date: September 16, 2004
    Inventor: Abraham Haskin
  • Patent number: 6788743
    Abstract: The amount of data transmitted in a primary data channel is increased by modulating a reference clock signal of the primary data channel with secondary data to form a separate secondary data channel. Primary data is formed into a primary data signal using the modulated reference clock signal, and a transmitter transmits the primary data signal to a receiver. The receiver recovers the primary data and modulated reference clock signal from the primary data signal, and then recovers the secondary data from the recovered modulated reference clock signal.
    Type: Grant
    Filed: October 11, 2000
    Date of Patent: September 7, 2004
    Assignee: LSI Logic Corporation
    Inventor: John W. Pfeil
  • Patent number: 6765519
    Abstract: A computation circuit operates in the modulation domain to generate a signal having phase modulation proportional to the ratio of the dividend (numerator) signal to the divisor (denominator) signal. The phase modulated signal may be demodulated by a phase demodulator to produce a baseband quotient signal. The divisor signal maintains inverse proportional control of the modulation gain of the modulator by varying the carrier injection level, resulting in higher bandwidth and accuracy, and lower drift and offset compared to traditional analog computation techniques. The circuit may contain all linear components, even though the division function is a non-linear function. The circuit and method operate when the input signals are analog or both are in the modulation domain.
    Type: Grant
    Filed: December 23, 2002
    Date of Patent: July 20, 2004
    Assignee: Agilent Technologies, Inc.
    Inventor: Richard K. Karlquist
  • Publication number: 20040131127
    Abstract: A method of converting RF to base-band signals, or base-band to RF signals, using a novel receiver and transmitter architecture, implementable on a RFIC. The method uses a two-stage conversion sequence: RF to base-band followed by base-band to intermediate frequency in the receiver, and an opposite sequence in the transmitter. A preferred embodiment of the architecture uses a double balance quadrature demodulator (208) for the RF to base-band down-conversion, and an image reflect quadrature modulator (230) for the base-band to intermediate frequency conversion. The architecture is further enhanced to perform power saving and dual-band reception and transmission.
    Type: Application
    Filed: November 26, 2003
    Publication date: July 8, 2004
    Inventors: Zivi Nadiri, Raviv Melamed
  • Publication number: 20040077310
    Abstract: A method for transmitting data signals between nodes in a networking system having one or more signal splitters. The method comprises transmitting wired and wireless data signals between nodes at a same frequency at which the effective isolation of each signal splitter at that frequency is substantially less than the specified effective isolation of each splitter. The invention also provides a wired networking system comprising one or more signal splitters. Each node in the system is configured to transmit and receive wired and wireless data signals over the system at a same frequency at which the effective isolation of each splitter is less than the specified effective isolation of each splitter.
    Type: Application
    Filed: August 14, 2003
    Publication date: April 22, 2004
    Inventor: David Levy
  • Patent number: 6614853
    Abstract: Transmission method in which angle-modulated pulses with temporally opposite angle modulation are generated in the receiver during the duration of the pulse, which pulses are superimposed by means of a first superimposing element (8, 9), in each case in pairs, into a folded pulse, whereby the folded pulses transmitted to the receiver, after a modulation process, carry information impressed upon them, and these folded pulses are filtered at the receiver through two parallel-connected, complementary dispersion filters with frequency-dependent group delay characteristics, whereby the frequency-dependent group delay characteristics of the two dispersion filters are matched to the angle-modulation, in each case, of one of the two pulses forming in their superposition the folded pulse, in such a way that at the output of the dispersion filter, in each case, a combined signal appears that consists of one compressed pulse with increased amplitude and one expanded pulse with decreased amplitude, whereby the signals at
    Type: Grant
    Filed: April 26, 1999
    Date of Patent: September 2, 2003
    Assignee: Nanotron Gesellschaft fur Mikrotechnik mbH
    Inventors: Manfred Koslar, Zbigniew Ianelli
  • Patent number: 6603809
    Abstract: A modulator, and an associated method, are described for use by a sending station, operable in a communication system, to communicate data to a receiving station upon a communication channel susceptible to fading. The modulator includes a mapper for mapping modulator output symbols to a set of antennas. The modulator ensures that an Orthogonality Condition is satisfied to impart maximum transmission diversity upon the data sent over the fading communication channel.
    Type: Grant
    Filed: December 29, 1999
    Date of Patent: August 5, 2003
    Assignee: Nokia Corporation
    Inventor: Dumitru Mihai Ionescu
  • Patent number: 6567474
    Abstract: A system for communicating signals between a transmitter and a receiver using digital modulation techniques is provided. This invention is particularly adapted to meet the requirements of power line communication. In one preferred embodiment of this invention the modulation technique is differential binary phase shift key modulation. This system provides a low cost, simple delay and multiply process for the modulation and demodulation of data. This system lends itself to an ASIC implementation, thereby further reducing the cost of the system while improving the reliability of the system in a noisy environment.
    Type: Grant
    Filed: March 2, 1999
    Date of Patent: May 20, 2003
    Assignee: Phonex Corporation
    Inventors: Scott R. Bullock, Scott D. Smith, David B. Bartholomew
  • Patent number: 6563880
    Abstract: A system and method for transmitting digital information through a medium such as atmospheric free-space includes a transmitter which generates a signal based on a basis set of mutually orthogonal, spectrally-shaped, sequences of substantially equal length and having predetermined autocorrelation values. The sequences may resemble noise in at least some of their characteristics. The orthogonality or cross-correlation characteristics, the autocorrelation characteristics and the resemblance to noise are due to features derived from sequences of pseudo-random numbers which themselves resemble noise in at least some of their characteristics. The waveform set based on the sequences is modulated digitally. The modulated set may be summed together along with a wideband reference signal of reduced amplitude and optionally an FM analog signal to form a composite signal which is broadcast typically through free space to at least one receiver.
    Type: Grant
    Filed: April 22, 1999
    Date of Patent: May 13, 2003
    Assignee: Ibiquity Digital Corporation
    Inventors: Bill J. Hunsinger, Derek D. Kumar
  • Patent number: 6553080
    Abstract: A communication system and method for continuous phase modulation providing for transmission of a phase-modulated carrier having a phaseform representative of concurrently transmitted symbols. The phaseform of the phase-modulated signal is a sum of shift bi-orthogonal functions, each term in that sum being weighted by one of the overlapping symbols. The communication system and method provide full-response demodulation for the recovery of a particular symbol from among the concurrently transmitted symbols by selecting a receiving filter function shift bi-orthogonal to the transmitter filter function corresponding to the particular symbol. The communication system and method then provide for nulling, by integration over a time interval during which the particular symbol is transmitted, those transmitter filter functions that do not correspond to the particular symbol. This results in the separation of the particular symbol from the other concurrently transmitted symbols.
    Type: Grant
    Filed: January 3, 2001
    Date of Patent: April 22, 2003
    Assignee: FutureWave, Inc.
    Inventors: Howard L. Resnikoff, Mark Tigerman
  • Patent number: 6522697
    Abstract: Systems and methods that increase the maximum data rate capacity per optical carrier on an optical link. The present invention intensity modulates an optical carrier with one or more (microwave) carriers that have been higher order modulated (M-ary ASK, PSK, QAM, and the like) using bandwidth efficient modulation. Consequently, as the number of bits/symbol is increased, the bit rate increases without an increase in occupied bandwidth. Thus, 2 bit/Hz or more of optical channel bandwidth may be transmitted.
    Type: Grant
    Filed: February 11, 1999
    Date of Patent: February 18, 2003
    Assignee: Lockhead Martin Corporation
    Inventor: Ralph Spickermann
  • Patent number: 6512474
    Abstract: A method and system to create an ultra wideband (UWB) signal are disclosed. The UWB signal comprises a carrier frequency with each cycle reversing in phase. The UWB signal is generated from a limited number of high power narrow band amplifiers. Each amplifier's output signal is combined to produce the desired UWB signal. The combination may occur in a combiner network or in free space.
    Type: Grant
    Filed: May 23, 2001
    Date of Patent: January 28, 2003
    Assignee: Lockhead Martin Corporation
    Inventor: Albert Pergande
  • Patent number: 6483880
    Abstract: Radio equipment for communicating digital data includes a clock modulation part for angular-modulation of a clock signal by a given modulation signal; and a data processing part processing the digital data based on the clock signal angular-modulated in the clock modulation part and producing angular-modulated digital data. In the radio equipment, levels of harmonics generated from the clock signal and the digital data are reducible.
    Type: Grant
    Filed: November 9, 1999
    Date of Patent: November 19, 2002
    Assignee: Fujitsu Limited
    Inventor: Yukihiro Moriyama
  • Publication number: 20020159538
    Abstract: Method for wireless information transfer, in particular for mobile communications, in which an input signal (s1, g4) is subjected to a modulation in a transmitter (2 to 8) and reaches a receiver (11 to 15) through a transmission channel, whereby angle modulated pulses, carrying information and possessing a frequency spectrum, are generated in the transmitter in such a way that they can be time compressed in a receiver by means of a filter (13) with frequency dependent, differential delay time, also known as group delay, in such a way, that pulses arise with shortened duration and increased amplitude compared to the emitted pulses, and at least a portion of the information is imprinted onto the pulses using an additional modulation, independent of the angle modulation, and/or is used for controlling a parameter of the angle modulation that can then be registered in the receiver.
    Type: Application
    Filed: May 9, 2002
    Publication date: October 31, 2002
    Applicant: Nanotron Gesellschaft Fur Mikrotechnik Mbh
    Inventors: Manfred Koslar, Zbigniew Ianelli
  • Patent number: 6441694
    Abstract: A method and apparatus for generating digitally modulated signals in which a serial data stream of digital signals to be modulated (70) is provided, the serial data stream being converted into real and imaginary components (74) which are then converted into a complex polar signal (80) representing the serial data stream. A carrier of appropriate frequency is generated by an infinite impulse response filter (84,86) and the polar signal is mixed with the output of the infinite impulse response filter to provide a representation of the complex polar signal modulated at the frequency generated by the infinite impulse response filter (88). Subsequently the imaginary component of the resulting representation is stripped from the signal (90) and the real component of the resulting representation is applied to a digital to analog converter (92) to produce an analog version of the serial data stream.
    Type: Grant
    Filed: December 15, 2000
    Date of Patent: August 27, 2002
    Assignee: Motorola, Inc.
    Inventors: Randy L. Turcotte, Stephen Chihhung Ma, Matthew A. Ronning, Keith V. Warble, Peter O. Okrah
  • Patent number: 6427121
    Abstract: A communications system for determining the position and velocity of an object using a plurality of GPS signals transmitted by a plurality of GPS sources includes an interrogator remote from the object and responsive to the plurality of GPS signals. The interrogator transmits an RF signal including GPS source information and at least one of frequency information and time and code phase information of at least one of the GPS signals. The system also includes a transponder positioned on the object and responsive to the RF signal and the plurality of GPS signals. The transponder tracks one of the plurality of GPS signals in response to the GPS source information and the frequency information and time and code phase information. The transponder generates a correlation snapshot and transmits the snapshot to the interrogator.
    Type: Grant
    Filed: July 12, 2001
    Date of Patent: July 30, 2002
    Assignee: SiRF Technology, Inc.
    Inventor: Keith J. Brodie
  • Publication number: 20020094034
    Abstract: Radio equipment for communicating digital data includes a clock modulation part for angular-modulation of a clock signal by a given modulation signal; and a data processing part processing the digital data based on the clock signal angular-modulated in the clock modulation part and producing angular-modulated digital data. In the radio equipment, levels of harmonics generated from the clock signal and the digital data are reducible.
    Type: Application
    Filed: November 9, 1999
    Publication date: July 18, 2002
    Inventor: YUKIHIRO MORIYAMA
  • Publication number: 20020085644
    Abstract: A final 15-bit output code word is generated in response to every 8-bit input code word by referring to a set of encoding tables. The encoding tables contain output code words assigned to input code words, and contain state information accompanying each output code word. The state information designates an encoding table among the encoding tables which is used next to generate an output code word immediately following the output code word accompanied with the state information. When given conditions are satisfied, first and second candidate current output code words generated in response to a current input code word by referring to first and second specified ones of the encoding tables. One is selected from the first and second candidate current output code words as a final current output code word in response to DSV calculation results. Auxiliary information is superimposed on a sequence of final output code words.
    Type: Application
    Filed: November 13, 2001
    Publication date: July 4, 2002
    Inventors: Atsushi Hayami, Takayuki Sugahara
  • Publication number: 20020071495
    Abstract: Systems and methods for enhancing the linearity of a modulator by filtering a set of frequency components from the modulator output to develop a modulator feedback signal. In a preferred embodiment of the invention, a diplexer separates the output of a balanced modulator into a first frequency spectrum and a second frequency spectrum. The first frequency spectrum contains the modulated output signal, and the second frequency spectrum contains the modulator feedback signal which is combined with the modulating signal to enhance the linearity of the modulator.
    Type: Application
    Filed: April 28, 1998
    Publication date: June 13, 2002
    Inventor: LEONID STRAKOVSKY
  • Patent number: 6381265
    Abstract: A digital signal processing circuit for field programmable radio frequency communications system including a digital controlled numerical controlled oscillator (NCO), dual digital signal conditioning circuits, and dual mixer circuits. The various circuits are responsive to digital commands for configuring the digital signal processing circuit to function with a variety of signaling schemes or waveforms. When configuring for angle modulation, a single conditioning and mixer is used and the modulating digital input signal is up converted to the center frequency of the NCO by the conditioning circuit and applied to an offset input of the NCO.
    Type: Grant
    Filed: November 3, 1998
    Date of Patent: April 30, 2002
    Assignee: Harris Corporation
    Inventors: Clifford Hessel, Michael E. Kreeger
  • Patent number: 6362701
    Abstract: An IC modulation processor (28) may be configured to operate in a single chip mode to accommodate baud rates up to a maximum clock rate for the processor (28) and in a dual chip mode to accommodate baud rates in excess of the maximum clock rate. The IC modulation processor (28) performs digital processing on a communication signal which conveys an input data stream (22). A pulse shaping filter (54-57) is provided following a phase mapper (50). The pulse shaping filter (54-57) is implemented as a pair of half-filters. Pulse shaping is distributed between two IC modulation processors (28) in the dual chip mode. An interpolator (86) and linearizer (106) follow the pulse shaping filters (54-57).
    Type: Grant
    Filed: November 9, 2000
    Date of Patent: March 26, 2002
    Assignee: Sicom, Inc.
    Inventors: Eric Martin Brombaugh, John M. Liebetreu, Bruce A. Cochran, Ronald D. McCallister
  • Publication number: 20010043656
    Abstract: Method for wireless information transfer, in particular for mobile communications, in which an input signal (s1, g4) is subjected to a modulation in a transmitter (2 to 8) and reaches a receiver (11 to 15) through a transmission channel, whereby angle modulated pulses, carrying information and possessing a frequency spectrum, are generated in the transmitter in such a way that they can be time compressed in a receiver by means of a filter (13) with frequency dependent, differential delay time, also known as group delay, in such a way, that pulses arise with shortened duration and increased amplitude compared to the emitted pulses, and at least a portion of the information is imprinted onto the pulses using an additional modulation, independent of the angle modulation, and/or is used for controlling a parameter of the angle modulation that can then be registered in the receiver.
    Type: Application
    Filed: April 26, 1999
    Publication date: November 22, 2001
    Applicant: Nanotron Gesellschaft Fur Mikrotechnik MBH
    Inventors: MANFRED KOSLAR, ZBIGNIEW IANELLI
  • Patent number: 6317468
    Abstract: A method and apparatus are provided for modulating an intermediate frequency of a radio frequency transmitter with a digital sample stream. The method includes the steps of interpolating the digital sample stream by an over sampling factor and modulating the interpolated digital sample stream to a single bit sample stream, while spreading and shaping quantization noise created by the modulation outside a bandwidth of the intermediate frequency. The method further includes the steps of converting the single bit sample stream to an analog signal and bandpass filtering the analog signal around the intermediate frequency.
    Type: Grant
    Filed: June 17, 1998
    Date of Patent: November 13, 2001
    Inventor: Ronald R. Meyer
  • Patent number: 6298099
    Abstract: A communication system and method for continuous phase modulation providing for transmission of a phase-modulated carrier having a phaseform representative of concurrently transmitted symbols. The phaseform of the phase-modulated signal is a sum of shift bi-orthogonal functions, each term in that sum being weighted by one of the overlapping symbols. The communication system and method provide full-response demodulation for the recovery of a particular symbol from among the concurrently transmitted symbols by selecting a receiving filter function shift bi-orthogonal to the transmitter filter function corresponding to the particular symbol. The communication system and method then provide for nulling, by integration over a time interval during which the particular symbol is transmitted, those transmitter filter functions that do not correspond to the particular symbol. This results in the separation of the particular symbol from the other concurrently transmitted symbols.
    Type: Grant
    Filed: December 22, 1999
    Date of Patent: October 2, 2001
    Assignee: FutureWave, Inc.
    Inventors: Howard L. Resnikoff, Mark Tigerman
  • Patent number: 6298093
    Abstract: Apparatus for phase/frequency digital modulation includes a digital circuit receiving and processing a digital modulation input signal to generate a digital modulation control signal, a digital-to-analog converter coupled to the digital circuit converts the digital modulation control signal into an analog modulation control signal, and an RF/analog circuit is coupled to the digital-to-analog converter. The RF/analog circuit includes a voltage controlled oscillator to generate a modulated output signal in response to the analog modulation control signal, and a quadrature tuner coupled to the voltage controlled oscillator generates an in-phase tuner output and a quadrature tuner output in response to the modulated output signal. An analog-to-digital converter is coupled to the quadrature tuner and converts the in-phase tuner output and the quadrature tuner output to digital in-phase and quadrature tuner outputs.
    Type: Grant
    Filed: August 5, 1999
    Date of Patent: October 2, 2001
    Assignee: Raytheon Company
    Inventor: Thad J. Genrich
  • Patent number: 6292655
    Abstract: There is provided a selective calling radio-receiver including (a) a demodulator demodulating a received selective calling radio signal, (b) a waveform-shaper shaping waveform of a demodulation signal transmitted from the demodulator, (c) a data-receiving signal generator generating a data-receiving signal which is in synchronization with the modulation signal having a waveform having been shaped by the waveform-shaper, and which has a plurality of pulses per a symbol term, (d) a data-receiver receiving the demodulation signal at every pulse of the data-receiving signal, (e) a sign discriminator discriminating a sign of received data at every symbol, based on data having been received in the data-receiver, and (f) a processor processing the received data a sign of which has been discriminated by the sign discriminator.
    Type: Grant
    Filed: May 27, 1999
    Date of Patent: September 18, 2001
    Assignee: NEC Corporation
    Inventor: Hisashi Kondo
  • Publication number: 20010016013
    Abstract: Ultra high spectral efficient Feher Keying (FK) Modulation and Demodulation (Modem), Baseband Processing (BBP), Intermediate Frequency (IF) and Radio Frequency (RF) signal generation and processing methods and implementations, including Clock Modulated (CM) and Shaped Clocked (SC) Transmitters-Receivers (transceivers) are disclosed. Additional embodiments, including Feher Quadrature Shift Keying (FQPSK) and Feher Quadrature Modulation (FQAM), in conjunction with CM and SC are also described. In the FK modulator, specified clock converted and clock shaped signal parameters are generated. These are based on the input data signal patterns and are generated by means of control signals, which are designed in the data input signal interface data signal and/or clock signal encoder units.
    Type: Application
    Filed: December 7, 2000
    Publication date: August 23, 2001
    Inventor: Kamilo Feher
  • Publication number: 20010002924
    Abstract: A duplex-system digital-data transmitting apparatus includes a digital-data signal source which outputs serial data at a signal output end. The level of the data is converted by a first level converter circuit. The data is supplied to an FSK modulator circuit to be FSK-modulated. Carriers are, for example, at 11 MHz and 13 MHz and correspond to digital signals “1” and “0”, respectively. The modulated signal is amplified by a driver and is coupled to the human body by a capacitor of about 100 pF. When the human body comes into contact with an electrode, the modulated signal transmitted through the human body is amplified by a pre-amplifier, demodulated by a demodulator circuit, and shaped by a comparator. The level of the shaped signal is converted by a second level converter circuit, and the signal is supplied to a serial input end of a receiving unit. Transmission and reception are performed using a half-duplex system.
    Type: Application
    Filed: December 1, 2000
    Publication date: June 7, 2001
    Inventor: Shigeru Tajima
  • Publication number: 20010001008
    Abstract: A transmitter encodes a number 2N data bits by using N data bits to select one of 2N levels of a cosine wave and the other N data bits to select one of 2N levels of a sine wave. The modulation attains the cosine wave levels at instants offset by half an N-bit symbol interval with respect to the sine wave levels, and is called Offset QAM (OQAM). A received OQAM signal is amplified, filtered and digitized at a sampling rate of preferably only one sample per N-bit half-symbol interval. Successive N-bit half-symbols comprise information modulated alternately on a cosine and a sine carrier wave. The receiver may remove this successive rotation by applying successive derotations of successive digitized samples by like amounts. The derotated samples are then correlated with known sync half-symbols. The sync correlations determine a set of channel coefficients describing the dependence of each digitized sample on one or more unknown half-symbols.
    Type: Application
    Filed: December 6, 2000
    Publication date: May 10, 2001
    Inventor: Paul W. Dent
  • Patent number: 6205184
    Abstract: The present system increases the number of channels in a given communication band by using narrow or very narrow band frequency modulation (FM) or phase modulation (PM). The system also improves sound quality, increases the signal-to-noise ratio, increases the power of the transmitted information, and/or achieves high selectivity, high fidelity and/or low distortion. Narrow band FM or PM signal communication can be implemented by transmitting a signal with a narrow or very narrow frequency spectrum, receiving the signal, converting the received signal to an IF (intermediate frequency) signal, and then expanding the narrow frequency deviation of the FM or PM signal. The narrow band frequency deviation may be expanded by frequency-multiplying the IF signal. A discriminator may then convert the frequency-deviation-multiplied signal to a low frequency signal or audio signal for further processing.
    Type: Grant
    Filed: December 29, 1995
    Date of Patent: March 20, 2001
    Inventor: Abdullah A. Al-Eidan
  • Patent number: 6192085
    Abstract: A circuit arrangement with a data sequence generator for the generation of an oscillator signal as a sequence of digital data, and having the following circuit parts: a first multiplication unit driven by a first auxiliary signal and a first control signal, where the first control signal corresponds to the sine of a manipulated variable that determines the frequency of the oscillator signal; a second multiplication unit driven by a second auxiliary signal, where the second control signal corresponds to the cosine of the manipulated variable; a third multiplication unit driven by a third auxiliary signal and a third control signal, where the third control signal corresponds to the sum of the first and second control signal; a first adding unit driven by the first multiplication unit and third multiplication unit; a second adding unit driven by the first multiplication unit and the second multiplication unit; a first time-delay unit driven by the first adding unit, where the oscillator signal is provided as a t
    Type: Grant
    Filed: June 29, 1998
    Date of Patent: February 20, 2001
    Assignee: Temic Telefunken microelectronic GmbH
    Inventor: Bernd Vetters
  • Patent number: 6185248
    Abstract: A wideband digital microwave receiver includes a plurality of channels. Each channel includes an I sub-channel and a Q-sub-channel. Each channel also has a comb generator. Each sub-channel has a mixer for multiplying the signal from the comb generator and an input to that sub-channel. By offsetting the combs used in the channels, the true solution may be selected from a number of false solutions. This may be achieved by cross-multiplying outputs from the I sub-channels and cross-multiplying outputs from the Q sub-channels. The signal information may be stored in a buffer and pre-processed. The single true solution is output to a digital signal processor and/or a monitoring unit.
    Type: Grant
    Filed: March 12, 1998
    Date of Patent: February 6, 2001
    Assignee: Northrop Grumman Corporation
    Inventor: Richard J. Wiegand
  • Patent number: 6184756
    Abstract: A low frequency signal generating portion 1 generates a first discrete signal (a signal sampled at a first sampling rate f1). A band pass portion 2 operates at a second sampling rate f2, performs a frequency selecting operation to a second discrete signal generated when the first discrete signal generated by the low frequency signal generating portion 1 is inputted, and generates a modulated signal with a prescribed center frequency.
    Type: Grant
    Filed: July 21, 1998
    Date of Patent: February 6, 2001
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Koichiro Tanaka, Hiroshi Oue, Kazuhiro Shouno
  • Patent number: 6097259
    Abstract: A modulator and modulation method for orthogonally modulating digital baseband signals include interpolation filters that frequency convert the frequencies of an in-phase component and a quadrature phase component of a digital baseband signal to four times the frequency of an intermediate frequency. .DELTA..SIGMA. modulation circuits are provided and .DELTA..SIGMA. modulate the frequency converted signals. A low pass filter is provided to remove unnecessary components from the .DELTA..SIGMA. modulated signals. A switching circuit selects a signal that has passed through the low pass filter according to an order of an in-phase component, a code inverted component of a quadrature phase component, a code inverted component of the in-phase component and the quadrature phase component, and outputs these signals as a digital orthogonal signal. An N bit D/A converter converts the digital orthogonal signals into analog orthogonal signals.
    Type: Grant
    Filed: September 28, 1998
    Date of Patent: August 1, 2000
    Inventors: Yoshiko Saito, Mitsuru Uesugi
  • Patent number: 5995552
    Abstract: Radio equipment for communicating digital data includes a clock modulation part for angular-modulation of a clock signal by a given modulation signal; and a data processing part processing the digital data based on the clock signal angular-modulated in the clock modulation part and producing angular-modulated digital data. In the radio equipment, levels of harmonics generated from the clock signal and the digital data are reducible.
    Type: Grant
    Filed: November 29, 1995
    Date of Patent: November 30, 1999
    Assignee: Fujitsu Limited
    Inventor: Yukihiro Moriyama
  • Patent number: 5907584
    Abstract: The system and method of the present invention include a modulator which encodes data on a communication signal using angle modulation. The demodulator, receiving the angle modulated communication signal, angle demodulates the angle modulated communication signal to obtain the data. In this manner, separate frequency bands are not required to transmit both the communication signal and the data. The bandwidth of the transmission from the modulator is reduced to the frequency band of the angle modulated communication signal. Additionally, since angle modulations of an audio signal are inaudible to a listener, when the communication signal is an audio signal, the angle modulated audio signal may be directly output to a listener at the demodulator. A multitude of applications exist for the present invention including Lincompex communication.
    Type: Grant
    Filed: November 14, 1995
    Date of Patent: May 25, 1999
    Assignee: Link Plus Corporation
    Inventor: J. Howard Leveque