31
Charles L Saxe, Roydn Jones: Anti-aliasing filter circuit for oscilloscopes. Tektronix, John P Dellett, November 4, 1986: US04621217 (102 worldwide citation)

A digital storage oscilloscope is provided with an anti-aliasing filter circuit utilizing a first plurality of switchable analog filters that bandwidth limit frequencies greater than half the oscilloscope's sampling frequency, and a digital transversal filter effective at lower sweep rates and sampl ...


32
Donald W Becker, Thomas R Bilotta: Digital receiver for variable data rate communications. TV COM Technologies, Baker Maxham Jester & Meador, March 18, 1997: US05612975 (101 worldwide citation)

A digital receiver includes a tuner and a demodulator that obtains a modulated signal carried in a received analog signal. A digital-to-analog converter operates at a preselected fixed sampling rate on the modulated signal to produce a first sequence of digitized samples. The first sequence of digit ...


33
Petrus J Van Gerwen, Rudolf A Van Doorn, Wilfred A M Snijders, Hendrik A Van Essen: Filter and demodulation arrangement. U S Philips Corporation, Thomas A Briody, William J Streeter, Henry I Steckler, December 19, 1978: US04130806 (100 worldwide citation)

A digital filter and demodulation arrangement for passband signals, whose corresponding baseband signal has a bandwidth limited to a given maximum frequency. The passband signals are filtered according to two bandpass characteristics which, apart from their asymmetrical distortion relative to their ...


34
Kenichi Terai, Hiroyuki Hashimoto, Isao Kakuhari: Noise control system. Matsushita Electric Industrial, Ratner & Prestia, July 9, 2002: US06418228 (99 worldwide citation)

A noise control system includes: a control sound generator for generating a control sound; an error detector for detecting an error signal between the control sound and noise; a noise detector for detecting a noise source signal; an adaptive filter for outputting a control signal; and a coefficient ...


35
Bruce D Signore, Eric J Swanson: Method and apparatus for calibration of a monolithic voltage reference. Crystal Semiconductor Corporation, Gregory M Howison, August 8, 1995: US05440305 (97 worldwide citation)

A method and apparatus for calibration of errors in a monolithic reference includes a bandgap voltage reference (50) that outputs an untrimmed voltage and a temperature voltage. The untrimmed voltage and temperature voltage are input to a delta-sigma A/D converter (52) which has the output thereof p ...


36
Adrian B Early, Larry L Harris, Michael J Callahan Jr: Digitally calibrated delta-sigma analog-to-digital converter. Crystal Semiconductor, Gregory M Howison, July 24, 1990: US04943807 (95 worldwide citation)

A self-calibrated analog-to-digital converter with a corrected output includes an analog modulator (18) for receiving an analog input voltage and outputting a pulse train having a value proportional to the analog input voltage. The pulse train is filtered by a digital filter (20) which has the outpu ...


37
Bernd Prohaska, Hans Dieter Schwartz, Rudolf Winkelmann, Gerhard Zettl: Digital filter switch for data receiver. Siemens Aktiengesellschaft, Hill Van Santen Steadman & Simpson, February 16, 1988: US04726041 (93 worldwide citation)

A digital filter switch for use with a data receiver incorporates first and second squaring units connected to the outputs of first and second band-pass filters tuned to the separation and character frequencies in a signal transmission. The outputs of the squaring units are interconnected via an add ...


38
Philippe Sehier, Cyril Bertrand: Multirate receive device and method using a single adaptive interpolation filter. Alcatel, Sughrue Mion Zinn Macpeak & Seas PLLC, August 3, 1999: US05933467 (92 worldwide citation)

A device for receiving a source digital signal transmitted at one or more source symbol frequencies F.sub.s samples a received analog signal transposed into the baseband and delivers an entirely demodulated sample signal. The sampling frequency F.sub.e complies with the generalized sampling conditio ...


39
Gary N Mills, Habib Homayoun: Wrist-worn ECG monitor. Instromedix, Kolisch Hartwell Dickinson McCormack & Heuser, March 1, 1994: US05289824 (91 worldwide citation)

A compact, lightweight wrist-worn cardiac data and event monitor having dry skin electrodes integral with the monitor's housing is disclosed. Preferably, the skin electrodes are made of titanium nitride-plated stainless steel and form inner, wrist-contacting, and outer, other hand's palm-contactable ...


40
Mohammad Rez Karim, Robert Louis Cupo, Mohsen Sarraf, Mohammad Zarrabizadeh: Fast frame synchronization. Agere Systems, Istrate Ionescu, December 31, 2002: US06501810 (91 worldwide citation)

A receiver for receiving synchronized digital transmissions organized in frames, each frame having a frame start, has a clock for generating pulses at time intervals with respect to a time reference and a counter for generating a count of the time intervals with respect to the time reference. A/D co ...