1
Tsuguo Maru: Portable radio apparatus having battery saved channel scanning function. NEC Corporation, Laff Whitesel Conte & Saret, December 11, 1990: US04977611 (84 worldwide citation)

A portable radio apparatus may operate in a battery saving mode on any one of a plurality of channels, in order to communicate with a central office. The apparatus selects a channel for its use on a basis of the strength of the electrical fields on the various channels. During an initial period the ...


2
Tsuguo Maru: Encoder and decoder by LDPC coding. NEC Corporation, March 20, 2012: US08140930 (41 worldwide citation)

The present invention is intended to provide an LDPC coding scheme which is capable of efficiently implementing a high-performance and high-speed encoder and decoder of an error correcting code suitable for the field of communications such as mobile communications. As to the configuration, a Tanner ...


3
Tsuguo Maru: Security module for radio telephone. NEC Corporation, Sughrue Mion Zinn Macpeak & Seas, September 22, 1992: US05150412 (35 worldwide citation)

A security module for a radio telephone prevents a KEY code stored in a non-volatile memory from being read out for illicit use. The security module deletes the KEY code stored in the memory when accessed from the outside. Hence, although a KEY code can be written to the memory or the operation of t ...


4
Masaki Ichihara, Tsuguo Maru: Quadrature modulator having circuit for correcting phase error. NEC Corporation, Sughrue Mion Zinn Macpeak & Seas, October 11, 1994: US05355101 (17 worldwide citation)

A quadrature modulator substantially completely compensating a phase error existing between two quadrature carriers by calculating two corrected baseband signals. One corrected baseband signal is generated by adding a common phase component signal and an orthogonal phase component signal after multi ...


5
Tsuguo Maru: Fully differential amplifier including common mode feedback circuit. NEC Corporation, Whitham Curtis Whitham & McGinn, October 22, 1996: US05568089 (17 worldwide citation)

In a fully differential amplifier so configured that an operating point potential of positive and negative output terminals of a differential amplifier having an active load is set by a common-mode feedback circuit, the common-mode feedback circuit includes a first differential pair receiving a refe ...


6
Tsuguo Maru: Digital automatic gain control linearizer and digital automatic gain control circuit using the same. NEC Corporation, Dickstein Shapiro Morin & Oshinsky, April 22, 2003: US06553084 (14 worldwide citation)

A digital automatic gain control linearizer for controlling a variable gain control element for automatically controlling gain, using an analog signal obtained by converting input digital data includes a memory an average calculation unit. The memory outputs upper and lower limit data corresponding ...


7
Tsuguo Maru: Timing recovery circuit for manchester coded data. NEC Corporation, Sughrue Mion Zinn Macpeak and Seas, April 28, 1987: US04661965 (12 worldwide citation)

A timing recovery circuit for recovering timing signals out of split phase or Manchester coded data, comprising dotting (DOT), frame synchronization (FS) and information (DATA) in digital form. A digital voltage controlled oscillator (VCO) provides a signal whose frequency is twice that of the timin ...


8
Tsuguo Maru: Turbo-code decoder. NEC Corporation, Sughrue Mion PLLC, February 4, 2003: US06516444 (11 worldwide citation)

A turbo-code decoder includes a first reception signal memory, second reception signal memory, a priori memory, first adder, first selector, and second selector. The first reception signal memory stores an information sequence. The second reception signal memory stores first and second parity sequen ...


9
Tsuguo Maru: Multi-dimensional pseudo noise generating circuit for soft-decision decoding. NEC Corporation, Dickstein Shapiro Morin & Oshinsky, June 11, 2002: US06405341 (11 worldwide citation)

A multi-dimensional pseudo noise generating circuit for soft-decision decoding, comprising: PN generating means for generating a signal of binary length code; a memory for storing a threshold level based on predetermined probability density function; address generating means for generating an addres ...


10
Tsuguo Maru: High-speed cell search system for CDMA. NEC Corporation, Young & Thompson, May 7, 2002: US06385180 (10 worldwide citation)

In a high-speed search system for CDMA, plural (M) symbols which are subjected to spread frequency coding with a spreading code called as a short code are prepared when synchronization of the spreading code is established before synchronization of carrier is established in a mobile station used in a ...