Pulse Position, Frequency, Phase Or Spacing Demodulator Patents (Class 329/313)
  • Patent number: 10122184
    Abstract: A docking station for electronic devices is disclosed. The docking station includes: a housing defining a docking area for receiving an electronic device; a vibrator for generating vibrations, the vibrator being positioned in the docking station such that vibrations generated by the vibrator are transmitted to at least a part of the electronic device when the electronic device is docked in the docking area; and a controller coupled to the vibrator, the controller being configured to: detect that the electronic device is docked in the docking area; and in response to detecting that the electronic device is docked in the docking area, cause the vibrator to generate vibrations corresponding to a signal representing an identifier of the docking station.
    Type: Grant
    Filed: September 15, 2016
    Date of Patent: November 6, 2018
    Assignee: BLACKBERRY LIMITED
    Inventors: Mohammed Nawaf Smadi, Jeffrey Ronald Clemmer
  • Patent number: 9715263
    Abstract: A BMC processing circuit, a USB power delivery controller, a BMC reception method, and a program capable of achieving stable BMC reception processing with low power consumption are provided. A BMC processing circuit 1100 includes an edge detection unit 1102 that detects change edges of a reception signal encoded by a Biphase Mark Code (BMC) method; an interval measuring unit 1103 that measures an interval value, the interval value being a period between the change edges; a threshold determination unit 1105 that corrects a first threshold using a plurality of interval values to generate a second threshold; and a BMC decoding unit 1107 that decodes the reception signal using the second threshold.
    Type: Grant
    Filed: November 23, 2015
    Date of Patent: July 25, 2017
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventor: Toshiyuki Nagase
  • Patent number: 9287851
    Abstract: A method and system for designing and implementing a finite impulse response (FIR) filter to create a plurality of output signals, each output signal having the same frequency but at a different phase shift from the other output(s), is described. Values are determined for the resistors, or other elements having impedance values, in a FIR filter having a plurality of outputs, such that each output has the same frequency response but a different phase than the other output(s). This is accomplished by the inclusion of a phase factor in the time domain calculation of the resistor values that does not change the response in the frequency domain. The phase shift is constant and independent of the frequency of the output signal.
    Type: Grant
    Filed: March 7, 2012
    Date of Patent: March 15, 2016
    Assignee: ESS Technology, Inc.
    Inventors: A. Martin Mallinson, Hu Jing Yao, Dustin Forman
  • Publication number: 20140062588
    Abstract: A method includes demodulating a load modulated signal at an initiator device based at least partially on a phase adjusted comparison value corresponding to the load modulated signal.
    Type: Application
    Filed: March 6, 2013
    Publication date: March 6, 2014
    Applicant: QUALCOMM Incorporated
    Inventors: RaviKiran Gopalan, Koorosh Akhavan, Le Nguyen Luong
  • Patent number: 8625661
    Abstract: Systems and methods for the pulse edge modulation of digital carrier signals for communications systems. A digital carrier signal is generated and the carrier is pulse edge modulated with digital data. A pulse edge modulated signal is generated by either retarding or advancing each pulse edge of a carrier to be modulated relative to its original position in time, depending on the state of the digital bit to be modulated on that edge.
    Type: Grant
    Filed: May 12, 2009
    Date of Patent: January 7, 2014
    Assignee: Alfred E. Mann Foundation for Scientific Research
    Inventors: Edward K. F. Lee, Eusebiu Matei
  • Patent number: 8525585
    Abstract: An object is to provide a demodulation circuit having a sufficient demodulation ability. Another object is to provide an RFID tag which uses a demodulation circuit having a sufficient demodulation ability. A material which enables a reverse current to be small enough, for example, an oxide semiconductor material, which is a wide bandgap semiconductor, is used in part of a transistor included in a demodulation circuit. By using the semiconductor material which enables a reverse current of a transistor to be small enough, a sufficient demodulation ability can be secured even when an electromagnetic wave having a high amplitude is received.
    Type: Grant
    Filed: July 26, 2012
    Date of Patent: September 3, 2013
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Takanori Matsuzaki, Yutaka Shionoiri
  • Patent number: 8258862
    Abstract: An object is to provide a demodulation circuit having a sufficient demodulation ability. Another object is to provide an RFID tag which uses a demodulation circuit having a sufficient demodulation ability. A material which enables a reverse current to be small enough, for example, an oxide semiconductor material, which is a wide bandgap semiconductor, is used in part of a transistor included in a demodulation circuit. By using the semiconductor material which enables a reverse current of a transistor to be small enough, a sufficient demodulation ability can be secured even when an electromagnetic wave having a high amplitude is received.
    Type: Grant
    Filed: February 14, 2011
    Date of Patent: September 4, 2012
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Takanori Matsuzaki, Yutaka Shionoiri
  • Patent number: 8254437
    Abstract: A transmitting apparatus, receiving apparatus and communication system are disclosed, and great improvement in an S/N ratio, preventing an actual throughput from decreasing, and preventing the number of circuits for synchronizing spread spectrum signals from increasing can be expected at the receiving apparatus side. The transmitting apparatus includes a pulse generating circuit, pulse repetition cycle determining circuit, peak power determining circuit, and modulator. The pulse generating circuit generates pulse strings, pulse repetition cycle determining circuit determines, based on a clock signal, a pulse repetition cycle of the pulse string generated by the pulse generating circuit. The peak power determining circuit determines a pulse peak power of the pulse string. The modulator modulates the pulse string with transmission data, and then generates a transmission signal.
    Type: Grant
    Filed: March 9, 2006
    Date of Patent: August 28, 2012
    Assignee: Panasonic Corporation
    Inventors: Suguru Fujita, Masahiro Mimura, Kazuaki Takahashi, Yoshinori Kunieda, Noriyuki Ueki
  • Patent number: 8054915
    Abstract: The invention relates to a method for adjusting a pulse detection threshold consisting in detecting a pulse when the edge of said pulse envelop crosses the threshold, in allocating (A) a staring value (TH0) to the threshold and in adjusting (B1) the threshold (TH) in such a way that the number of pulses detected on at least one observation window (OWj) satisfies a predetermined criterion in a determined time.
    Type: Grant
    Filed: December 22, 2006
    Date of Patent: November 8, 2011
    Assignee: France Telecom
    Inventors: Jean Schwoerer, Benoît Miscopein
  • Patent number: 8044744
    Abstract: A method and apparatus is described for a time modulated signal. A cosine function is used as the basis for the signal with time intervals at the maximum and minimum values of the cosine function defining the encoded data. The received waveform is twice differentiated to provide a cosine function from which zero crossings are detected and the time intervals determined.
    Type: Grant
    Filed: August 1, 2008
    Date of Patent: October 25, 2011
    Assignee: And Yet, Inc.
    Inventor: Martin H. Graham
  • Patent number: 8014483
    Abstract: A receiver in an impulse wireless communication. The receiver (300) includes a pulse-pair correlator (304) that receives a signal (316) and divides it into two signals for paths. One of the signals is input to signal multiplier (312) while another signal is delayed by a delay unit (310). The signal multiplier (312) multiplies the received signal (316) by a delayed signal (318). An integrator (314) integrates an output signal (322) over a designated period of time. An adding module (306) sums an output signal (324) from the integrator (314). An acquiring module (308) compares an summing-up output (326) from the adding module (306) with a predetermined threshold value to detect the existence of a transmitting-standard preamble.
    Type: Grant
    Filed: November 4, 2005
    Date of Patent: September 6, 2011
    Assignee: Panasonic Corporation
    Inventors: Yew Soo Eng, Zhan Yu
  • Patent number: 7881397
    Abstract: Methods and systems for modulating a signal are described. A phase-modulated signal that includes a sequence of contiguous one-cycle sinusoidal waveforms having a frequency above 50 MHz is generated. The phases of the one-cycle sinusoidal waveforms correspond to symbols of a message signal. A bandwidth of the phase-modulated signal is reduced using a bandpass filter centered at the frequency of the contiguous one-cycle sinusoidal waveforms. The phase-modulated signal is wirelessly transmitted.
    Type: Grant
    Filed: March 31, 2005
    Date of Patent: February 1, 2011
    Assignee: Teradyne, Inc.
    Inventor: Toshihide Kadota
  • Patent number: 7868689
    Abstract: An apparatus and method for communications is disclosed. The apparatus includes a slicer configured to generate samples of a signal carrying information, and a demodulator having a digital integrator configured to integrate the samples, the demodulator being further configured to recover from the integrated samples data representative of the information carried by the signal.
    Type: Grant
    Filed: April 8, 2008
    Date of Patent: January 11, 2011
    Assignee: QUALCOMM Incorporated
    Inventors: Chong U. Lee, Amal Ekbal, David Jonathan Julian, Jun Shi, Supisa Lerstaveesin
  • Publication number: 20100295608
    Abstract: Rather than using an external sampling clock to perform time-to-digital conversion function, input signal is self-sampled by its own delayed signals. A demodulation method utilizing delayed-self-sampling technique, comprising steps of: obtaining a signal processed by a limiting amplifier as the only input signal required for demodulation; transferring the limiting amplified signal via two paths, by one of which the limiting amplified signal is directly sent to an input end of a delayed-self-sampler, and by the other of which the limiting amplified signal is sent to a delay line for generating and outputting time delayed signals; sampling the limiting amplified signal by time delayed signals from the delay line with delayed-self-sampler to generate a group of sampled data; and converting the group of sampled data by a thermometer-to-binary converter into a group of binary codes, which is input into data decision circuitry to be processed into recovered base-band data.
    Type: Application
    Filed: August 4, 2010
    Publication date: November 25, 2010
    Inventors: Ming-Jen YANG, Hong-Sing KAO
  • Patent number: 7620095
    Abstract: A bidirectional direct sequence spread spectrum half-duplex RF modem. that can be applied to transmit and receive numerous types of analog and digital pulse modulation. The modem incorporates a SAW based correlator for performing the spreading and de-spreading functions in the transmitter and receiver. A programmable frequency synthesizer provides the frequency source for various signals in the modem including the local oscillator (LO), IF interrogating pulse and clock signals. An upconverter/downconverter provides frequency translation to the desired frequency band. Pulse gating and interrogating pulse shaping are employed to reduce the spectral side bands of the transmitted spread pulse. The RF modem operates as an analog or digital pulse transmitter and receiver. It is adapted to be generic and is versatile enough to be used in many different types of data communication systems, such as OOK, PWM and PPM.
    Type: Grant
    Filed: June 14, 2006
    Date of Patent: November 17, 2009
    Assignee: Vishay Intertechnology Inc
    Inventor: David Ben-Bassat
  • Publication number: 20090251208
    Abstract: An apparatus and method for communications is disclosed. The apparatus includes a slicer configured to generate samples of a signal carrying information, and a demodulator having a digital integrator configured to integrate the samples, the demodulator being further configured to recover from the integrated samples data representative of the information carried by the signal.
    Type: Application
    Filed: April 8, 2008
    Publication date: October 8, 2009
    Applicant: QUALCOMM Incorporated
    Inventors: Chong U. Lee, Amal Ekbal, David Jonathan Julian, Jun Shi, Supisa Lerstaveesin
  • Patent number: 7449945
    Abstract: A phase demodulator has a high frequency amplifier which amplifies a received signal modulated by phase, a voltage control oscillator which conducts oscillation operation in tune with the received signal amplified by the high frequency amplifier, a phase comparator which detects a phase difference between an output signal of the voltage control oscillator and a reference oscillation signal, and a demodulator which conducts demodulation process based on the phase difference.
    Type: Grant
    Filed: December 12, 2005
    Date of Patent: November 11, 2008
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takashi Kawakubo, Toshihiko Nagano, Michihiko Nishigaki
  • Patent number: 7414463
    Abstract: A PPM signal demodulator for demodulating a PPM signal transmitted in a UWB radio communication system includes a rectifier for rectifying a received PPM signal to obtain an absolute value signal, integrator and comparators for integrating the absolute value signal for every first, second and third integral times and comparing the integrated values for the integral times, absolute value circuits for converting respective outputs of the integrator and comparators to corresponding absolute values, moving average circuits for moving-averaging respective outputs of the absolute value circuits, a determining circuit for generating demodulation data on the basis of the integrated and compared result by the integrator and comparator, and a main control for generating, on the basis of the outputs of the moving average circuits, integral interval control signals that control the first, second and third integral times to supply them to the respective integrator and comparators.
    Type: Grant
    Filed: March 8, 2007
    Date of Patent: August 19, 2008
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Hiroji Akahori, Yoshihito Shimazaki
  • Patent number: 7388911
    Abstract: An FM broadcast transmitter transmits a broadcast signal having a carrier at a broadcast frequency and sidebands, able to be transmitted at full power, within a transmission bandwidth around the carrier. It includes a source of a modulated FM stereo signal having a carrier at the broadcast frequency and having sidebands with a bandwidth less than the transmission bandwidth representing a stereo signal. It also includes a source of a modulated in-band-on-channel (IBOC) signal, having carrier pulses spaced relative to each other to represent the IBOC digital data signal encoded as a variable pulse width encoded signal, and a bandwidth within the transmission bandwidth not overlapping the FM stereo signal sidebands. A signal combiner combines the modulated FM stereo signal and the modulated IBOC signal to form the broadcast signal.
    Type: Grant
    Filed: August 4, 2004
    Date of Patent: June 17, 2008
    Assignee: Thomson Licensing
    Inventors: Chandra Mohan, Zhiming Zhang, Manuel Apraez
  • Patent number: 7336736
    Abstract: The invention allows the detection and processing in a radio signal received by a receiver, of any signal of “pulsed” type present in radio signals applied to the input of a radiofrequency receiver, the receiver having an analogue/digital converter for performing the coding into digital on N bits of P successive samples of the analogue signal applied to the input of the receiver and a computer for processing the said digital signals, characterized in that on the basis of a histogram of the rate of occupancy of the digitized samples, graded in ranges Fx of amplitude-increasing sample levels, is determined, from among the ranges Fx, a range Fn onwards of which the total number of digitized samples Nnor contained in the ranges Fn and those below Fn is greater than or equal to a normality threshold Nn, Nn being a number predetermined as a function of the sensitivity of the detection of pulsed signals that one wishes to achieve.
    Type: Grant
    Filed: November 26, 2002
    Date of Patent: February 26, 2008
    Assignee: Thales
    Inventors: Valéry Leblond, Franck Letestu, Alain Renard
  • Patent number: 7221215
    Abstract: A PPM signal demodulator for demodulating a PPM signal transmitted in a UWB radio communication system includes a rectifier for rectifying a received PPM signal to obtain an absolute value signal, integrator and comparators for integrating the absolute value signal for every first, second and third integral times and comparing the integrated values for the integral times, absolute value circuits for converting respective outputs of the integrator and comparators to corresponding absolute values, moving average circuits for moving-averaging respective outputs of the absolute value circuits, a determining circuit for generating demodulation data on the basis of the integrated and compared result by the integrator and comparator, and a main control for generating, on the basis of the outputs of the moving average circuits, integral interval control signals that control the first, second and third integral times to supply them to the respective integrator and comparators.
    Type: Grant
    Filed: March 2, 2005
    Date of Patent: May 22, 2007
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Yoshihito Shimazaki, Hiroji Akahori
  • Patent number: 6970496
    Abstract: A bidirectional direct sequence spread spectrum half-duplex RF modem that can be applied to transmit and receive numerous types of analog and digital pulse modulation. The modem incorporates a SAW based correlator for performing the spreading and de-spreading functions in the transmitter and receiver. A SAW resonator fabricated on the same monolithic substrate provides the frequency source for the oscillator. An upconverter/downconverter provides frequency translation to the desired frequency band. Pulse gating and interrogating pulse shaping are employed to reduce the spectral side bands of the transmitted spread pulse. The RF modem operates as an analog or digital pulse transmitter and receiver. It is adapted to be generic and is versatile enough to be used in many different types of data communication systems, such as OOK, PWM and PPM. The RF modem can be used as the physical (PHY) layer in a layered communication system such as the ISO OSI communication stack.
    Type: Grant
    Filed: October 13, 2000
    Date of Patent: November 29, 2005
    Assignee: RF Waves Ltd.
    Inventors: David Ben-Bassat, Moshe Lerner
  • Patent number: 6940892
    Abstract: A spread spectrum transmission apparatus includes, a chip clock generation section which outputs a chip clock in one frame formed of M+L?1 chips, a frame clock generation section which outputs a frame clock synchronized to frame occurrence timing, SS-PPM signal generation sections each of which inserts a pseudonoise code sequence corresponding to one period from some of M chips located at a head of a frame based on K-bit transmission data and generates an SS-PPM signal, delay sections which respectively delay N SS-PPM signals respectively by determined delay quantities, and a multiplexing section which adds up all of outputs respectively of the delay units and generates a multiplexed SS-PPM signal.
    Type: Grant
    Filed: March 14, 2002
    Date of Patent: September 6, 2005
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Seiji Okubo, Tatsuya Uchiki, Toshiharu Kojima
  • Patent number: 6903603
    Abstract: A quadrant deciding section decides the quadrant to which a received signal belongs based on a baseband signal. A rotation projector rotates the received signal and projects the rotated signal to a straight line that intersects orthogonally at the origin with a straight line that bisects the decided quadrant. An integrator integrates the signal after the projection. A one-bit quantizer quantizes the integration result by deciding the sign of the integration result. A delay circuit delays the quantized signal by a predetermined time. An adder adds the decision result and the quantized signal modulo the phase 2?. A low-pass filter sequentially latches phase values after the addition with internal shift registers, converts the phase value to a prescribed specific value when the phase values that cross over 2? exist in the whole data within the registers, and averages the phase values.
    Type: Grant
    Filed: February 14, 2002
    Date of Patent: June 7, 2005
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Ryoji Hayashi
  • Patent number: 6788219
    Abstract: A mud pulse telemetry technique that uses a number of bits per interval based on parameters of the pulse position modulation system in order to reduce data transfer time in a pulse position modulation system. More particularly, depending on parameters of the pulse position modulation such as the minimum-time and the bit-width, it may be possible to decrease overall transmission time by splitting values having a larger number of bits into multiple transmissions with each transmission having a smaller number of bits.
    Type: Grant
    Filed: November 27, 2002
    Date of Patent: September 7, 2004
    Assignee: Halliburton Energy Services, Inc.
    Inventors: Cili Sun, Laban M. Marsh, Bipin K. Pillai
  • Patent number: 6700931
    Abstract: A radio frequency identification (RFID) tag device having a pulse position modulation (PPM) decoder circuit which calculates a relative frequency relationship between an internal clock-oscillator of the RFID tag device and an external PPM source such as a RFID tag reader, and then synchronizes the RFID tag device PPM decoder circuit to the required precision for reliable PPM symbol decoding. The PPM decoder is synchronized by measuring the “counts per pulse” (CPP) from a calibration cycle having a plurality of pulses in a single symbol frame.
    Type: Grant
    Filed: July 6, 2000
    Date of Patent: March 2, 2004
    Assignee: Microchip Technology Incorporated
    Inventors: Youbok Lee, Lee Furey, Sam Alexander, William F. Gallagher, Ron Salesky, Shinichiro Inui
  • Patent number: 6566941
    Abstract: The invention discloses a phase detection method including a quadrant determining procedure, a first comparison procedure, a second comparison procedure, a coordinate transforming procedure, and a phase computing procedure. A first and a second phase approximate values are obtained in the quadrant determining procedure and the first comparison procedure. A third phase approximate value is obtained in the second comparison procedure and the coordinate transforming procedure. A total phase is computed in the phase computing procedure. Using this method, we does not need to consult look-up tables to determine the phase, thus saving a lot of memory space. The invention also provides a phase detection device.
    Type: Grant
    Filed: August 14, 2001
    Date of Patent: May 20, 2003
    Assignee: Syncomm Technology Corp.
    Inventor: Chun Lin Guo
  • Publication number: 20020190786
    Abstract: A high-performance demodulator for use in UWB (Ultra WideBand) multiple-access communication is disclosed. In a communication device, the correlation between a received signal corresponding to signals transmitted from a plurality of communication terminals by means of UWB (Ultra WideBand) communication and pulses at possible positions in a signal transmitted from each communication terminal is calculated. On the basis of the resultant calculated correlation, and taking into account interference among the signals transmitted from the communication terminals, the received signal is demodulated into original data issued by the respective communication terminals.
    Type: Application
    Filed: March 5, 2002
    Publication date: December 19, 2002
    Inventors: Young C. Yoon, Ryuji Kohno
  • Patent number: 6442200
    Abstract: A demodulating circuit demodulates a PPM signal obtained as a result of modulation performed in accordance with a PPM method. This circuit includes a detecting portion and a control portion. The detecting portion detects a predetermined carrier pulse provided within a symbol period of the PPM signal, using a clock signal having a frequency double or higher than double the transmission rate of the PPM signal. The controlling portion stops supply of the clock signal to the detecting circuit after the detecting portion detects the predetermined carrier pulse until the subsequent symbol period starts.
    Type: Grant
    Filed: July 1, 1998
    Date of Patent: August 27, 2002
    Assignee: Ricoh Company, Ltd.
    Inventor: Ryoh Fukui
  • Patent number: 6426716
    Abstract: A range gated microwave motion sensor having adjustable minimum and maximum detection ranges with little response to close-in false alarm nuisances such as insects or vibrating panels. The sensor resolves direction of motion and can respond to target displacement in a selected direction and through a selected distance, in contrast to conventional hair-trigger motion sensors. A constant false alarm rate (CFAR) detector prevents false triggers from fluttering leaves, vibrating machinery, and RF interference. The sensor transmits an RF pulse and, after a modulated delay, mixes echo pulses with a mixer pulse. Thus, the echo pulses are modulated at the mixer output while transmit and mixer pulse artifacts remain unmodulated and easily filtered from the output. Accordingly, the sensor only responds to echoes that fall within its minimum and maximum range-gated region, and not to close-in or far-out objects.
    Type: Grant
    Filed: February 27, 2001
    Date of Patent: July 30, 2002
    Assignee: McEwan Technologies, LLC
    Inventor: Thomas E. McEwan
  • Patent number: 6359525
    Abstract: A digital data modulator includes a source of a plurality of digital data signals having a common data bit period. A plurality of encoders each encode a corresponding one of the plurality of digital data signals using a variable pulse width code having edges occurring in respective non-overlapping intervals within the data bit period. A plurality of pulse signal generators each generate respective pulses representing the edges of the corresponding one of the encoded plurality of digital data signals. A carrier signal generator generates a carrier signal having carrier pulses corresponding to the respective pulses.
    Type: Grant
    Filed: July 25, 2000
    Date of Patent: March 19, 2002
    Assignee: Thomson Licensing S.A.
    Inventors: Chandra Mohan, Jayanta Majumdar
  • Publication number: 20020017949
    Abstract: The present invention provides an apparatus and a method for determining a pulse position for a signal encoded by a pulse modulation. The signal being receivable as at least a first component (PCS) and a second component (DCS). A first storage unit (102) stores at least one symbol of the first component (PCS) and a second storage unit (104) at least one symbol of the second component (DCS). A determination unit (118) comprises a probability table (110), which in case that the first and second components (PCS, DCS) are received is addressed with the at least one symbol of the first component (PCS) and the at least one symbol of the second component (DCS). Thereby, the probability table (110) provides a value that is defined as the pulse position (DDS).
    Type: Application
    Filed: July 10, 2001
    Publication date: February 14, 2002
    Inventors: Fritz Gfeller, Walter Hirt
  • Patent number: 6310906
    Abstract: A chaotic carrier pulse position modulation communication system and method is disclosed. The system includes a transmitter and receiver having matched chaotic pulse regenerators. The chaotic pulse regenerator in the receiver produces a synchronized replica of a chaotic pulse train generated by the regenerator in the transmitter. The pulse train from the transmitter can therefore act as a carrier signal. Data is encoded by the transmitter through selectively altering the interpulse timing between pulses in the chaotic pulse train. The altered pulse train is transmitted as a pulse signal. The receiver can detect whether a particular interpulse interval in the pulse signal has been altered by reference to the synchronized replica it generates, and can therefore detect the data transmitted by the receiver. Preferably, the receiver predicts the earliest moment in time it can expect a next pulse after observation of at least two consecutive pulses.
    Type: Grant
    Filed: August 18, 1999
    Date of Patent: October 30, 2001
    Assignee: The Regents of the University of California
    Inventors: Henry D. I. Abarbanel, Lawrence E. Larson, Nikolai F. Rulkov, Mikhail M. Sushchik, Lev S. Tsimring, Alexander R. Volkovskii
  • Patent number: 6295318
    Abstract: A system and associated methods that use separate paths to send amplified data. The method expands, or amplifies, the amount of data that can be transmitted over a dedicated bandwidth-limited communications medium by using a first channel for transmitting clock synchronization pulses and transmitting the data as pulse position modulated (PPM) data over a second separate bandwidth-limited communication channel. Data for transmission is encoded by determining if the period of a pulse encroaches into the frame of the subsequent pulse. In response to a determination of encroachment, one or both of the pulses are inverted and time shifted to eliminate the encroachment. In the event that inversion of one or both of the pulses does not eliminate the encroachment, a blank is inserted between the two pulses.
    Type: Grant
    Filed: February 18, 1999
    Date of Patent: September 25, 2001
    Inventor: Peter F. Wingard
  • Patent number: 6292051
    Abstract: A simple demodulation circuit having a reduced hardware cost and an increased using flexibility is provided. Such architecture is used in a pulse position modulation for retrieving a data from a received source signal and includes a transformation circuit operating the source signal to produce a quantized data having a plurality of data slots, a slot address detector electrically connected to the transformation circuit for reaching a peak slot address from addresses of the data slots, and a timing recovery decoder electrically connected to the slot address detector for recovering the data through decoding the peak address.
    Type: Grant
    Filed: March 15, 1999
    Date of Patent: September 18, 2001
    Assignee: National Science Council
    Inventors: Chau-Chin Su, Ming-Hwa Hue, Chorng-Kuang Wang
  • Patent number: 6252453
    Abstract: A method for demodulating a modulated carrier includes sampling the modulated carrier with an A/D converter clocking at a first sampling frequency to generate a modulated carrier series of samples occurring at the first sampling frequency. The first sampling frequency it selected to optimize a digital signal processor (DSP) design from demodulating a carrier modulated in accordance with a first transmission specification to recover base band data. The method includes generating a second series of samples occurring at a second sampling frequency representing the base band data. The second series of samples is calculated from the first series of samples and the second sampling frequency is selected to optimal a DSP design for recovering data from the base band data signal encoded in accordance with a second transmission specification.
    Type: Grant
    Filed: January 20, 2000
    Date of Patent: June 26, 2001
    Assignee: Advanced Micro Devices, Inc.
    Inventor: Colin D. Nayler
  • Patent number: 6219380
    Abstract: A transceiver has a pulse position modulation (PPM) encoder, automatic gain control (AGC) circuit and timing recovery circuit. The PPM encoder illustratively has a frequency divider, slot selector, and mixer. The frequency divider divides the frequency of a clock signal to which the data of the non-return to zero (NRZ) signal are aligned to produce a half frequency clock signal. The slot selector selects pulses of the clock signal and the half frequency clock signal depending on logic values of the NRZ signal and a control signal to produce first and second slot selected signals. The mixer mixes the first and second slot selected signals to produce a PPM signal of the NRZ signal. The AGC circuit illustratively has a variable gain amplifier, a hysteresis comparator, an event detector, a timer, and a counter. The variable gain amplifier amplifies the PPM signal using a dynamically adjusted gain that depends on an inputted digital control value.
    Type: Grant
    Filed: January 6, 1998
    Date of Patent: April 17, 2001
    Assignee: Industrial Technology Research Institute
    Inventors: Wei-Chen Wang, Kuang-Hu Huang, Chorng-Kuang Wang, Ten-Long Dan
  • Patent number: 6205169
    Abstract: A first spread spectrum pulse position modulated signal with a pseudonoise code is generated. A second spread spectrum pulse position modulated signal with an inverted pseudonoise code is generated. A third spread spectrum pulse position modulated signal with a pseudonoise code is generated. A fourth spread spectrum pulse position modulated signal with an inverted pseudonoise code is generated. The first and second spread spectrum pulse position modulated signals are added together and thus a fifth spread spectrum pulse position modulated signal is formed. The third and fourth spread spectrum pulse position modulated signals are added together and thus a sixth spread spectrum pulse position modulated signal is formed. Quadrature modulation is performed on the fifth and sixth spread spectrum pulse position modulated signals.
    Type: Grant
    Filed: January 20, 2000
    Date of Patent: March 20, 2001
    Assignee: Ricoh Company, Ltd.
    Inventor: Masaru Nakamura
  • Patent number: 6169765
    Abstract: An output signal pulse width error correction circuit and method wherein errors in a data signal conforming to a communications protocol having a prescribed duty cycle are corrected by monitoring a duty cycle of the data signal, comparing the duty cycle to a duty cycle reference voltage corresponding to the prescribed duty cycle, and adjusting a pulse width of the data signal to conform to the prescribed duty cycle of the protocol. An embodiment is shown that low pass filters the input data signal to introduce greater slope to the input data signal which is then compared to a pulse width control voltage in order to generate an output data signal. The pulse width control voltage is produced by integrating the output data signal to obtain an average value corresponding to the duty cycle of the output data signal and comparing the average value to a duty cycle reference voltage corresponding to the prescribed duty cycle for the communications protocol.
    Type: Grant
    Filed: May 28, 1997
    Date of Patent: January 2, 2001
    Assignee: Integration Associates, Inc.
    Inventor: Wayne T. Holcombe
  • Patent number: 6108376
    Abstract: A system for receiving information encoded in a train of pulse position modulated signals and then decoding the pulse train to produce amplitude modulated signals representing the original information includes a circuit for detecting the beginnings of successive PPM signals, a one-shot multivibrator responsive to the beginnings of the PPM signals for producing pulse width signals whose duration varies in accordance with the received intelligence, and an R-C low pass output circuit coupled to the output of the multivibrator to produce amplitude modulated output voltage waves. The R-C circuit has a time constant substantially greater than the unmodulated period between PPM pulses, and produces a rising voltage that spans the time duration of an associated high voltage level square pulse and whose decaying voltage level varies in amplitude in accordance with the maximum voltage attained at the output of the R-C integrator by the trailing edge of the associated high voltage level pulse.
    Type: Grant
    Filed: December 12, 1996
    Date of Patent: August 22, 2000
    Inventors: Harry Clark Morgan, William Harsha Boyd
  • Patent number: 6081493
    Abstract: In a demodulator for a digital FM signal, the received digital FM signal is verified at the data bit boundaries for inversion to detect errors. If an uninverted data bit boundary is detected, those sections of the digital FM signal just preceding and just following the uninverted data bit boundary are modified thereby generating two modified signals. Using the error detecting code included in the digital FM signal, the two modified signals are evaluated to determine which modification corrects the errors and the modified signal with the correct modification is selected.
    Type: Grant
    Filed: March 4, 1999
    Date of Patent: June 27, 2000
    Assignee: Sony Corporation
    Inventor: Yoshiro Joichi
  • Patent number: 6066982
    Abstract: A pulse position modulation pulse signal to be demodulated is sampled by a pulse detection part based on a motion clock. The motion clock is generated from a motion clock generating part so that a period of pulse precision n falls within a width of an information pulse in the signal to be demodulated. A phase relationship between the motion clock and the information pulse to be demodulated is classified into six kinds of patterns, and in case the relationship is outside the patterns, it is to be excluded as being under effect of noise. The pulse detection part gives a pulse detection signal in which the effect of the noise has been eliminated to a phase comparison part, which compares the given signal with a reproduction clock timing signal showing the timing of a reproduction clock signal generated in a clock reproduction part, then generates a control signal for controlling a phase of the clock reproduction part.
    Type: Grant
    Filed: January 30, 1998
    Date of Patent: May 23, 2000
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Yoshihiro Ohtani
  • Patent number: 5977822
    Abstract: A method and apparatus for pulse position demodulation begins by receiving a pulse that is positioned approximately at one of a plurality of time intervals within a time chip, where the pulse has a pulse width that is greater than each of the plurality of time intervals. The decoding process then continues by determining the time interval in which a transition edge of the pulse lies. From the particular time interval, a set of bits is determined.
    Type: Grant
    Filed: April 4, 1998
    Date of Patent: November 2, 1999
    Assignee: Sigmatel, Inc.
    Inventors: Mathew A. Rybicki, H. Spence Jackson, Timothy W. Markison, Gregg S. Kodra, Michael A. Margules
  • Patent number: 5907528
    Abstract: In a demodulator for a digital FM signal, the received digital FM signal is verified at the data bit boundaries for inversion to detect errors. If an uninverted data bit boundary is detected, those sections of the digital FM signal just preceding and just following the uninverted data bit boundary are modified thereby generating two modified signals. Using the error detecting code included in the digital FM signal, the two modified signals are evaluated to determine which modification corrects the errors and the modified signal with the correct modification is selected.
    Type: Grant
    Filed: June 19, 1996
    Date of Patent: May 25, 1999
    Assignee: Sony Corporation
    Inventor: Yoshiro Joichi
  • Patent number: 5844942
    Abstract: A method for modulating a radio signal has the steps of: predetermining a first time interval so as to define a data word; generating a synchronization pulse, the synchronization pulse initiating a single data word having a length of the predetermined first time interval; and generating a single data pulse within the data word after a second time interval with respect to the synchronization pulse, the length of the second time interval defining at least one character. Defining at least one character by a single data pulse after a second time interval with respect to the synchronization pulse enhances an energy efficiency of the transmitted radio signal while mitigating a duty cycle thereof.
    Type: Grant
    Filed: February 27, 1997
    Date of Patent: December 1, 1998
    Assignee: Northrop Grumman Corporation
    Inventors: Randall G. Hicks, Warren E. Guthrie, James T. Wesley
  • Patent number: 5790032
    Abstract: An apparatus detects living bodies, in particular human living bodies, by ectromagnetic signals. The apparatus has a receiver device for electromagnetic signals that includes a device for obtaining frequency components that are characteristic in respect to living bodies, out of the magnetic signals. The receiver device includes a direct demodulator.
    Type: Grant
    Filed: September 8, 1996
    Date of Patent: August 4, 1998
    Assignee: Selectronic Gesellschaft fur Scherheitstechnik und Sonderelektronik mbH
    Inventor: Gerd Juergen Schmidt
  • Patent number: 5694435
    Abstract: The invention relates to a digital method of detecting pulses of short duration and an arrangement for implementing the method. A threshold value is generated by means of a statistical procedure which is common in radar engineering, by means of which short pulses to be detected can be differentiated as opposed to long pulses. The method includes sorting a predeterminable number of temporally consecutive signal samples by amplitude and creating a ranking of the signal samples. An associated amplitude value for a predeterminable rank within the ranking is determined and multiplied by a predeterminable weighting factor (k) so that an amplitude threshold value (SW) is generated. All signal samples whose amplitude is greater than the amplitude threshold value (SW) are then marked with a marking signal.
    Type: Grant
    Filed: December 21, 1994
    Date of Patent: December 2, 1997
    Assignee: Deutsche Aerospace AG
    Inventors: Hans-Georg Kolle, Gunter Wolf
  • Patent number: 5691665
    Abstract: A clock reproduction unit provides a reproduced clock signal from a received PPM signal. The results of sampling the PPM signal with a reproduced clock signal is held by a sample result holding unit. Symbol synchronization is achieved from a received PPM signal by a symbol synchronizing signal generation unit. According to the sample result, the reproduced clock signal, and symbol synchronization, a reception data reproduction unit analyzes the result of a plurality of previous samples to decode reception data according to a specific procedure.
    Type: Grant
    Filed: September 25, 1996
    Date of Patent: November 25, 1997
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Yoshihiro Ohtani
  • Patent number: 5661754
    Abstract: An infrared remote-control receiver employs at its front end a gyrator-configured transistor operating as a current-to-voltage converter, but derives its data information from a negative-going gyrator output pulse in preference to the more conventionally used positive-going pulse. This negative-going pulse may be wider than the positive-going pulse and reduces the bandwidth demand on subsequent processing circuitry. This enables low-bandwidth, low-current hardware to be used which makes the receiver ideal for use in battery-operated systems. Also, the negative-going pulse is easier to detect, as it directly follows a disturbance known to be in the opposite direction. The result is an increased receiver sensitivity.
    Type: Grant
    Filed: March 28, 1995
    Date of Patent: August 26, 1997
    Assignee: Plessey Semiconductors Limted
    Inventor: David Bernard Mapleston
  • Patent number: 5633742
    Abstract: An optical data communication and location apparatus for at least one location in a facility having at least one receiver at said at least one location. A plurality of portable transmitters provides optical wireless data links with the receiver. Each of the transmitters has a power supply with circuitry for transmitting data packets over said optical wireless data links to the receiver. The circuitry for transmitting data packets generates a data code having at least two time frames, each of the at least two times frames being divided into at least two data time slots. Each frame has exactly one pulse in one data time slot whereby in each data packet, there is encoded n-bits of binary data where 2.sup.n is equal to the number of time slots in each frame.
    Type: Grant
    Filed: September 21, 1995
    Date of Patent: May 27, 1997
    Assignee: Fisher Berkeley Corporation
    Inventor: Robert T. Shipley