1
Paul W Dent: Log-polar signal processing. Telefonaktiebolaget LM Ericsson, Burns Doane Swecker & Mathis, September 10, 1991: US05048059 (97 worldwide citation)

The invention relates to a method and an arrangement intended for radio communication systems and effective in digitalizing and subsequently processing numerically arbitrary radio signals. The signals are represented by composite (complex) vectors which have been subjected to disturbances in the sys ...


2
Barrie Gilbert: Logarithmic amplifier. Analog Devices, Wolf Greenfield & Sacks, February 5, 1991: US04990803 (66 worldwide citation)

A multi-stage logarithmic converter of the "successive-detection" or "progressive-compression" type including circuitry providing an accurate, temperature-stabilized logarithmic transfer function. The gain stages are DC-coupled throughout, though each also employs a demodulator comprising a full-wav ...


3
Marshall Christopher, Sauer Erich: Radio device with signal compression.. Koninkl Philips Electronics, Philips Patentverwaltung, May 4, 1994: EP0595406-A1 (60 worldwide citation)

A digital radio device (2) for inter alia mobile radio or cordless telephony is proposed with signal compression (12) for base band signals and/or hardlimiting at RF (6) an/or IF (10) stages. Such an architecture allows for a high level of integration with less complexity than known digital radio de ...


4
Norol T Evans: Improved radar receiver system. Hughes Aircraft Company, Wanda K Denson Low, April 26, 1994: US05307069 (56 worldwide citation)

An improved radar receiver having side lobe blanking and coherent side lobe cancellation circuits in the main receiver channel and a control arrangement that overcomes the conventional problem that the side lobe blanking circuit will also blank a noise jammer signal even after the coherent side lobe ...


5
Dennis W Ricker: Log-exponential AGC circuit. The United States of America represented by the Secretary of the Navy, R S Sciascia, Sol Sheinbein, Philip Schneider, April 21, 1981: US04263560 (52 worldwide citation)

An AGC circuit designed to have a response-time independent of the absolute ackground input level comprising a variable-gain amplifier, an envelope detector receiving an input from the variable-gain amplifier, a logarithmic amplifier to convert the envelope value to its logarithm, a summer to subtra ...


6
Kenneth R Haddad, Richard J Vilmur: Speakerphone for radio and landline telephones. Motorola, Rolland R Hackbart, December 22, 1987: US04715063 (49 worldwide citation)

Improved speakerphones (120 and 130 in FIG. 1) for both radio (112) and landline (138) telephones are described. The improved speakerphones (120 and 130) each include a microphone (102 and 132), a speaker (104 and 134) and unique control circuitry (106 and 136). The control circuitry of the improved ...


7
Barrie Gilbert: Synchronous logarithmic amplifier. Analog Devices, Alan T McCollom, March 29, 1994: US05298811 (35 worldwide citation)

A synchronous progressive-compression type logarithmic amplifier includes one or two channels of amplifier/limiter stages and a corresponding multi-stage synchronous demodulator circuit to provide low noise and/or low power operation as well as other useful operational modes. A preferred embodiment ...


8
William H Newman, Ralph G Burgess: Temperature measurements using thermistor elements. Massachusetts Institute of Technology, Robert F O Connell, May 26, 1992: US05116136 (34 worldwide citation)

A technique for measuring temperature by a thermistor sensor which technique provides for a linearization of the temperature sensed by the thermistor by utilizing circuitry which responds to the thermistor and produces an output which is an exponential function of the temperature sensed by the therm ...


9
Mead C Killion: Occlusion meter and associated method for measuring the occlusion of an occluding object in the ear canal of a subject. Etymotic Research, McAndrews Held & Malloy, November 26, 1996: US05577511 (32 worldwide citation)

An instrument for measuring the degree of occlusion of an occluding object, such as an earmold, in the ear canal of a subject is set forth that overcomes the problems associated with prior art devices. The instrument includes a first microphone for transducing sound waves exterior to the ear canal i ...


10
Katsuji Kimura: Logarithmic amplifier circuit. NEC Corporation, Helfgott & Karas, October 15, 1991: US05057717 (29 worldwide citation)

A logarithmic amplifier circuit has n (n>1) stages of differential amplifiers, n+1 in number, of rectifying circuits, a differential pair of bipolar transistors having different emitter sizes in the ratio of 1/J (J>1) and a differential pair of MOS transistors of which the ratio of a gate-width and ...