Adaptive equalizer included in the receiver for a data transmission system
I claim: 1. Adaptive equalizer in a receiver of a data transmission system, transmitting overlapping multilevel coded data signals across a transmitting medium having variable attenuation, said receiv... Read More
Inventors: Hulth, Maria T. V.;, Assignee: Telefonaktiebolaget L M Ericsson (Stockholm, SE) |
Wideband subcarrier multiplexed optical communication system operating over more than one octave
According to the present invention, these and other objects and advantages are achieved in apparatus for transmitting an optical signal, comprising a semiconductor laser diode for generating a light b... Read More
Inventors: Olshansky, Robert; Hill, Paul M.;, Assignee: GTE Laboratories, Incorporated (Waltham, MA) |
Optical sub-carrier multiplex television transmission system using a linear laser diode
Referring now to FIG. 1, there is shown an amplitude modulated-vestigial sideband sub-carrier multiplexed optical transmission system 10. Several baseband frequency modulation television channels 12,... Read More
Inventors: Bodeep, George E.; Darcie, Thomas E.; Flynn, Edward J.; Lipson, Jan; McGrath, Carl J.; Roxlo, Charles B.; Schaefer, Mark S.; Upadhyayula, L. C.;, Assignee: AT&T Bell Laboratories (Murray Hill, NJ) |
Method and device for training an adaptive equalizer by means of an unknown data signal in a transmission system using double sideband-quadrature carrier modulation
What is claimed is: 1. In a data receiver for a synchronous data transmission system wherein the data symbols are transmitted at the signaling rate 1/T, using a double sideband-quadrature carrier modu... Read More
Inventors: Godard, Dominique N.;, Assignee: International Business Machines Corp. (Armonk, NY) |
Technique for decision-directed equalizer train/retrain
FIG. 1 depicts a receiver 10 for data signals transmitted from a transmitter (not shown) over a bandlimited communication channel, e.g., voiceband telephone circuit. The data signals are illustrative... Read More
Inventors: Farrow, Cecil W.;, Assignee: American Telephone and Telegraph Company (New York, NY); AT&T Information Systems Inc. (Morristown, NJ) |
Adaptive convergent decision feedback equalizer
The aforementioned ISI estimation divergence problem with prior adaptive decision feedback equalizers is obviated in accordance with the present invention by taking two steps to reduce the probability... Read More
Inventors: Buttle, Kenneth G.;, Assignee: Level One Communications, Inc. (Folsom, CA) |
Automatic equalizer
Accordingly, it is an object of the present invention to provide an improved automatic equalizer that can eliminate the above-noted defects inherent in previously proposed systems. Another object of t... Read More
Inventors: Tanaka, Masato; Kan, Toshiya;, Assignee: Sony Corporation (Tokyo, JP) |
Circuit for sensing cable effects for automatic equalization
What is claimed is: 1. An automatic equalizer comprising: a variable equalizer having an input port to receive a digital signal from a transmission channel, an output port to provide an equalized digi... Read More
Inventors: McKibben, Barry A.;, Assignee: Tektronix, Inc. (Wilsonville, OR) |
Time domain automatic equalizer with frequency domain control
The principal object of the invention is to provide a time domain automatic equalizer which is controlled in the frequency domain. Another object of the invention is to provide a means for directly ca... Read More
Inventors: Perreault, Donald A.;, Assignee: Xerox Corporation (Stamford, CT) |
Quantized amplifier
What is claimed is: 1. An amplifier for coupling first and second energy sources to a load in accordance with an input signal, comprising: means for comparing only an instantaneous signal as developed... Read More
Inventors: Sturgeon, Clayton L.;, Assignee: Ranger Engineering Corporation (Fort Worth, TX) |
Fuze modulation system
I claim as my invention: 1. An improved noise-modulated distance-measuring fuze comprising in combination: an oscillator; a transmitting antenna coupled to said oscillator for radiating a signal towar... Read More
Inventors: Karr, Philip R.;, Assignee: The United States of America as represented by the Secretary of the Army (Washington, DC) |
Balanced tapped delay line spectral shaping differentiation circuit for signal detection
An object of the present invention is to provide a balanced delay line differentiator with built in spectral shaping equalization for waveform compensation. The above object has been achieved by means... Read More
Inventors: Lee, Patrick S.;, Assignee: Sperry Corporation (New York, NY) |
Variable equalizer
Accordingly, it is an object of the present invention to provide a variable equalizer which has a wide equalization range and allows an accurate equalization over a wide band. Another object of the pr... Read More
Inventors: Yumoto, Osamu; Suzuki, Toshiro; Takatori, Hiroshi; Takasaki, Yoshitaka;, Assignee: Hitachi, Ltd. (Tokyo, JP) |
Equalization of modulated data signals utilizing tentative and final decisions and replication of non-linear channel distortion
In order to understand the equalization technique of the present invention, it is first instructive to consider the characteristics of the QAM transmitter 100 and nonlinear channel 150 of FIG. 1 whic... Read More
Inventors: Lim, deceased, Tong L.; Yu, executor, by Keung-Yi P.; Gitlin, Richard D.;, Assignee: AT&T Information Systems Inc. (Holmdel, NJ) |
Digital automatic line equalizer with means for controlling tap gains of transversal filter based on mean power of output from the filter
It is an object of the present invention to provide a digital automatic line equalizer which can readily effect line equalization without use of the decided signal. As mentioned in the preamble, a dig... Read More
Inventors: Yamaguchi, Masaru; Ogata, Takenori;, Assignee: NEC Corporation (Tokyo, JP) |
Receiver for multivalued digital signals
It is an object of the invention to provide a receiver as set out in the preamble in which it no longer happens that the receiver does not start to operate properly or only after a lengthy adjusting t... Read More
Inventors: Verbakel, Johannes M. M.; Bogers, Antonius J. P.; Castello Da Costa, Paulo M.;, Assignee: U.S. Philips Corporation (New York, NY) |
Chopper amplifier for measuring low DC current
OF THE PREFERRED EMBODIMENT The basic circuit of the present invention is a transconductance amplifier driving a chopper. In this circuit, the transconductance amplifier 10 is constituted of an opera... Read More
Inventors: Wei, Sen-Jung;, Assignee: University of Maryland (College Park, MD) |
System for controlling the threshold setting of a field effect memory device
In carrying out the invention according to one form there is provided apparatus for setting the gate threshold voltage of a memory device having an input, an output and a gate to a predetermined volta... Read More
Inventors: Eberhard, Everett;, Assignee: Motorola, Inc. (Chicago, IL) |
Controllable electronic resistance device
What is claimed is: 1. An electronic resistance device comprising an amplifier having an input and an output, a first and a second terminal means for applying an input voltage, a voltage divider inclu... Read More
Inventors: Schemmel, Hans R.; Reichelt, Ingo;, Assignee: U.S. Philips Corporation (New York, NY) |
Fader circuit for vehicle sound system
The invention is directed to a two-channel audio amplifier for use with multi-speaker stereophonic sound reproduction systems of the type in which each audio channel includes first and second two-term... Read More
Inventors: Dressler, Roger W.;, Assignee: Motorola, Inc. (Schaumburg, IL) |
Method and apparatus for multipole acoustic wave borehole logging
The method and apparatus of this invention are for logging the compressional wave velocity, or the shear wave velocity, of the virgin earth formation surrounding a borehole but separated from the bore... Read More
Inventors: Winbow, Graham A.; Baker, Lawrence J.;, Assignee: Exxon Production Research Co. (Houston, TX) |
Velocity logger for logging intervals
I claim as my invention: 1. Apparatus for examining a formation through which a borehole extends, comprising means for transmitting a beam of pulses of ultrasonic acoustic energy from the borehole int... Read More
Inventors: Vogel, Charles B.;, Assignee: Shell Oil Company (Houston, TX) |
Range and depth detection system
Briefly described, the present invention is directed to a new and improved method, and apparatus for carrying out said method, for computing the range to and the depth of an object submerged within a ... Read More
Inventors: Lipsky, Alan H.;, Assignee: Subcom, Inc. (Glen Cove, NY) |
Shock absorbing subassembly
In accordance with the invention, the foregoing advantages have been achieved through the present shock absorbing subassembly. The shock absorbing subassembly of the present invention comprises a body... Read More
Inventors: Zabcik, Clarence J.;, Assignee: NL Industries, Inc. (New York, NY) |
Differential lever actuator including differentially force-transmitting members which are not liable to break
What is claimed is: 1. In a differential lever actuator comprising a driving member having an axis, a first end fixed to a base member, and a second end susceptible to a linear displacement along said... Read More
Inventors: Yano, Takeshi; Fukui, Izumu; Hamatsuki, Takeshige; Sato, Eiichi; Inui, Osamu;, Assignee: NEC Corporation (Tokyo, JP) |
Headband for removably securing stereo earphones
The present invention overcomes the deficiencies in the art and provides a headband combined with a set of earphones that will conveniently stay on a user's head. More particularly, the present invent... Read More
Inventors: Altman, Michaell A.;, Assignee: Consumer Advantage, Inc. (Tucker, GA) |
Asymmetrical sideband transmission with pseudo-stereo effects
In accordance with the present invention, there is provided an improved asymmetrical sideband AM transmitter which includes means, responsive to at least one supplied audio program signal, for develop... Read More
Inventors: Kahn, Leonard R.;, Assignee: |
Toll-call restriction system
What is claimed is: 1. In a toll-call restriction system useful with a telephone unit and a pair of telephone lines for restricting the telephone exchanges which can be reached from said telephone uni... Read More
Inventors: Mogtader, Charles S.;, Assignee: |
VTR With equalizer
I claim: 1. An arrangement for equalizing a video signal in a system in which the video signal is recorded in frequency modulated form and then played back upon frequency demodulation, wherein, in add... Read More
Inventors: Ilmer, Andreas;, Assignee: BASF Aktiengesellschaft (Ludwigshafen, DE) |
Loudspeaker arrangement
What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims. 1. A loudspeaker arrangement comprising an enclosure having a vertical axis and walls includin... Read More
Inventors: Ponsgen, Karl Otto;, Assignee: |
Audio Signal Processing 
