Did You Know...
...that in 1800 ether was first used by partyers as a fun diversion? Sniffing the gas led to hilarious and raucous laughter as people watched each other become more and more intoxicated and silly. Several doctors independently realized the value ether would have to anesthetize surgery patients. Of those who claimed rights to the "discovery," none had a happy ending. One had a seizure and died defending his rights. Another spent his life in an asylum because he had been denied acclaim. A third became addicted to chloroform and, in a New York City jail, he soaked a cloth in the drug, severed an artery and bled to death.
PatentStorm News
Make the Most of Our Site
See this month's Top Inventors and Most Cited Patents.
Stay on top of the latest innovations by subscribing to an RSS feed.
Registered users: Manage your profile.
| Number | Title | Issue Date |
| 7675358 | Semiconductor device The invention provides a semiconductor device that generates a clock signal with a fixed pulse width from a carrier. The invention also provides a semiconductor device where data can be obtained accurately from a carrier using a clock signal with a fixed pulse width... | 03/09/2010 |
| 6912249 | Method and system for training a radio receiver A system and method for training a radio receiver to mitigate the effects of ISI caused by multi-path includes receiving a header of a transmitted packet at the receiver, the header containing at least one flag to identify a corresponding reference training sequence... | 06/28/2005 |
| 6809584 | Signal transmission and receiving methods optimized for integrated circuit implementation A demodulator for demodulating a modulated input signal transmitted at a carrier frequency includes a current mirror for receiving the modulated input signal and generating a first and a second current-mirror output signals of same amplitude and frequency as the mod... | 10/26/2004 |
| 6668032 | Device and method for signal sampling at multiple clock rates A network receiver is configured for receiving a modulated carrier signal representing a data frame from another network transceiver via a network medium, the modulated carrier signal may be either a pulse position modulated (PPM) carrier, a quadrature am... | 12/23/2003 |
| 6483381 | Signal transmission and receiving methods optimized for integrated circuit implementation This invention discloses a demodulation method. The method includes steps of: A) Receiving a modulated input signal having an input signal frequency. B) Generating a first switch control signal at a first switching frequency substantially equal to the inp... | 11/19/2002 |
| 6441683 | Device and method for recovering frequency redundant data in a network communications receiver A demodulation circuit for recovering frequency redundant quadrature amplitude modulated data comprises an A/D converter generating digitized carrier signal. A mixer receives the digitized carrier and generates a frequency shifted I-signal and a frequency... | 08/27/2002 |
| 6301295 | AM modulated wave eliminating circuit The present invention provides an AM modulated wave eliminating circuit which is capable of extracting a digital modulated wave by cancelling an AM modulated wave from an AM data multiplex modulated wave. A composite wave is composed of an AM carrier wave... | 10/09/2001 |
| 6255901 | Demodulator for ask-modulated signals having small modulation depth A demodulator circuit for demodulating a signal ASK-modulated with modulation pulses equal in duration, and having a small depth of modulation and large dynamic range comprises an amplitude limiter (10) through which an amplitude-dependent current flows w... | 07/03/2001 |
| 5987068 | Method and apparatus for enhanced communication capability while maintaining standard channel modulation compatibility In a radio communication system (100), enhanced communication capability is provided while maintaining standard channel modulation compatibility. At a transmitter (110, 200, 600), a first information signal is generated from data according to a predefined... | 11/16/1999 |
| 5915028 | Amplitude demodulator An amplitude demodulator for demodulating a quadrature-amplitude modulated stereo signal for radio receivers, where a digital intermediate-frequency signal is constructed from a received signal, the intermediate-frequency signal is converted into a baseba... | 06/22/1999 |
| 5841814 | Sampling system for radio frequency receiver A radio frequency (rf) receiver adapted to receive a number of different digitally modulated rf input signals such as quadrature amplitude modulated (QAM) and vestigial side band (VSB) rf input signals includes circuitry for down converting the rf input s... | 11/24/1998 |
| 5673292 | AM-PSK system for broadcasting a composite analog and digital signal using adaptive M-ary PSK modulation A radio-frequency broadcasting system and method for simultaneously broadcasting analog and digital signals in a standard AM broadcasting channel wherein the system includes: a transmitter for providing, and broadcasting, a composite signal containing an ... | 09/30/1997 |
| 5602868 | Multiple-modulation communication system A multiple-modulation communication system includes a transmitter that modulates and transmits communication signals modulated by a first modulation technique and communication signals modulated by a second modulation technique. The first modulation techn... | 02/11/1997 |
| 5561716 | Demodulator In a demodulator for a stereo signal transmitted by amplitude and phase modulation of a carrier, a phase signal and a quantity signal are formed. By multiplication of the quantity signal with the tangent of the phase signal reduced by a value to be preset... | 10/01/1996 |
| 5469126 | I/Q-modulator and I/Q-demodulator An I/Q-modulator or I/Q demodulator circuit in which the modulating signals (2, 3) are input through the output phase transfer branches of the circuit. In relation to the RF-characteristics, a series resistor (16) and a series inductance (20) in the phase... | 11/21/1995 |
| 5095363 | Method of demodulating multi-standard TV signals and a circuit device for implementing the method A method of demodulating multi-standard TV signals consists of providing a plurality of signals at a frequency which is a multiple of a reference frequency whose value is a common submultiple of the frequencies of the multi-standard signals. Thereafter, t... | 03/10/1992 |
| 5077542 | Transmission system with suppressed carrier signal amplitude modulation preserving the polarity of the transmitted signal, and corresponding transmitter and receiver A system of transmission with amplitude modulation for the transmission of signals of all types, analog and/or digital, requiring high performance characteristics with respect to the noise induced by the transmission channel, comprising, at transmission, ... | 12/31/1991 |
| 4677690 | Baseband demodulator for FM and/or AM signals A demodulator of the type employed in a "zero-IF" system uses a local oscillator for providing quadrature output signals at the center frequency of a received signal to be demodulated. The demodulator has first and second mixers for separately mixing the ... | 06/30/1987 |
| 4631485 | Synchronous demodulator for amplitude modulated signals Two circuits carry out the beating of a modulated signal, with first and second signals, respectively, each having substantially the same frequency as the carrier of the modulated signal but phased-shifted relative to one another by 90°. A commutator con... | 12/23/1986 |
| 4589127 | Independent sideband AM multiphonic system An improved transmitter for a compatible independent sideband (ISB) AM stereo system develops a phase modulated carrier where the modulation represents the stereo difference signal inverse modulated by the stereo sum signal in accordance with a selected m... | 05/13/1986 |
| 4565970 | Precision harmonic rejecting demodulator with digital phase alignment A low-cost, two-axis rate and acceleration sensor utilizing piezoelectric generator elements affixed to a rotating structure and generating a periodic signal having an amplitude representing the rates and accelerations. A demodulator dividing the period o... | 01/21/1986 |
| 4525686 | Phase-locked loop circuit with variable bandwidth filter A phase-locked loop circuit comprises an oscillator, a phase comparator which compares the phase of an input signal with the phase of an oscillator signal, a detector which detects when the phase-locked loop circuit is locked within a predetermined freque... | 06/25/1985 |
| 4517520 | Circuit for converting a staircase waveform into a smoothed analog signal In converting a staircase waveform signal into a smoothed analog signal, this circuit can perform the high-quality conversion without any sophisticated lowpass filter. An input staircase signal is delayed for one stepping interval to produce a differentia... | 05/14/1985 |
| 4481646 | Method and apparatus for receiving a data signal modulated by means of a double sideband-quadrature carrier modulation technique A method and apparatus for receiving a data signal modulated by means of a double sideband-quadrature carrier modulation technique in which the received signal is sampled at a rate higher than the signaling rate 1/T, passed through a compensating filter, ... | 11/06/1984 |
| 4412181 | Process for the demodulation of an amplitude modulated signal and demodulator performing this process A process for the demodulation of an amplitude modulated signal composed of two suppressed carriers, at a same frequency F and in phase quadrature, which are respectively modulated by two modulation signals, the modulated signal being preceded by a refere... | 10/25/1983 |
| 4408097 | AM-FM Radio receiver for receiving AM-stereo signals An AM-FM receiver which uses the FM-demodulator for demodulating the phase modulated sidebands of an AM-stereo signal. Therefore, it has to operate as a FM-demodulator also at the AM-intermediate frequency which is achieved by means of a parallel resonant... | 10/04/1983 |
| 4349696 | AM Stereophonic demodulator circuit for amplitude/angle modulation system An AM stereophonic demodulator circuit for an amplitude/angle modulation system, comprising an AM detector circuit for producing a stereophonic sum signal (L+R), an FM or PM detector circuit for producing a stereophonic difference signal (L-R), and contro... | 09/14/1982 |
| 4300020 | Method and apparatus for eliminating pilot signal components from stereo demodulated signals A pilot signal cancelling signal is first combined with a composite stereo signal by a first predetermined ratio and thus a combined signal is fed to a stereo demodulator (3A) which produces a difference signal and an inverted difference signal, while the... | 11/10/1981 |
| 4249038 | Stereo decoder with 19KHz-pilot suppression and improved oscillator phase locking Stereo decoder for multiplex signals comprising a demultiplexer for decoding the left-hand and the right-hand sound signal of a stereo multiplex signal, a phase-locked loop which includes a phase-locked oscillator and a multiplicative phase detector, and ... | 02/03/1981 |
| 4238642 | Angle-modulated stereo system An angle-modulated transmitter generates a two-channel stereo wave by double-sideband angle modulation of a carrier with a first signal, double-sideband angle modulation of the same carrier, delayed less than 90°, with a second signal, and addition of th... | 12/09/1980 |
| 4236042 | Compatible AM stereo system employing a modified quadrature modulation scheme A compatible AM stereo system including a modified quadrature modulation scheme. Two stereo modulators are described which each generate composite modulated signals including a carrier component and two phase-shifted components. The two phase-shifted comp... | 11/25/1980 |
| 4215316 | AM stereo signal demodulation circuit A stereo signal demodulation for obtaining left and right channel signals from an input stereo signal. A differential amplifier is coupled to a constant current source and first and second multipliers are coupled to the differential amplifier. A dividing ... | 07/29/1980 |
| 4167650 | Stereo signal demodulating circuits A stereo signal demodulating circuit of a switching type is provided with a differential amplifier to obtain difference signals between two output signals from the switching circuit. The difference signals from the differential amplifier are added to the ... | 09/11/1979 |
| 4139738 | Multiplex decoder having a distortion-free differential amplifier In a multiplex decoder circuit comprising two pairs of transistor differential circuits driven by switching signals of a 38 kHz subcarrier signal, for separating a stereo composite signal into left and right channel signals, a differential amplifier forme... | 02/13/1979 |
| 4074075 | Circuit for demodulating a stereo signal A circuit for demodulating a composite stereo signal of the type including a main-channel (L+R) signal and a sub-channel (L-R) signal to derive therefrom individual channel information signals L and R, respectively. A switching circuit of the balanced-mod... | 02/14/1978 |
| 4054839 | Balanced synchronous detector circuit A balanced synchronous detector circuit for detecting the amplitude of a received signal and for detecting the phase difference between the received signal and a generated signal. A preferred application of this balanced synchronous detector circuit is in... | 10/18/1977 |
