Patents by Inventor Kenji Sekine
Kenji Sekine has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 6535069Abstract: A radio frequency power amplifier module for a dual-band type mobile communication apparatus that can transmit and receive a first frequency f1 and second frequency f2 (f2=2×f1). It includes a drive stage amplifier having the gain peaks at f1 and f2 with a matching circuit and a radio frequency power output circuit including a radio frequency power output transistor. The output circuit has a transmission line connected to the drain end of the output transistor, a parallel resonance circuit connected in series to the transmission line to resonate at harmonics of a frequency twice the frequency f2, a series resonance circuit provided between one end of the resonance circuit and the ground to resonate at harmonics of a frequency twice the frequency f2 and an output matching circuit provided in series to the other end of the parallel resonance circuit for matching with f1 and f2.Type: GrantFiled: February 28, 2002Date of Patent: March 18, 2003Assignee: Hitachi, Ltd.Inventors: Toru Fujioka, Isao Yoshida, Mineo Katsueda, Masatoshi Morikawa, Yoshikuni Matsunaga, Kenji Sekine, Osamu Kagaya
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Publication number: 20030048133Abstract: To provide a high frequency amplifying apparatus for reducing a phase change caused in switching to a different output level, a variable phase shifter is provided at at least one location of respective paths rearward from a branching circuit for switching a path on a high output side having an amplifier using a first semiconductor device at an output stage and a path on a low output side having an amplifier using a second semiconductor device with a smaller output than the first semiconductor device on an output stage in accordance with a desired output level. After branching and a phase length of the variable phase shifter is set to a pre-determined value such that passing phase lengths of the respective paths become substantially the same by passing either of the paths.Type: ApplicationFiled: August 19, 2002Publication date: March 13, 2003Inventors: Kenji Sekine, Tomonori Tanoue, Osamu Kagaya
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Publication number: 20030050039Abstract: The object of the present invention is to provide a cellular phone to be used for emergency reports that performs GPS positioning by means of remote control from an emergency report center, and transmits positional information to the emergency report center. The emergency report cellular phone according to the present invention is constituted such that when an emergency report switch thereof is depressed, a call request is made to the emergency report center. The emergency report center transmits a response signal with the result that a call link is formed between the emergency report cellular phone and the emergency report center. Following completion of the telephone call, the emergency report center transmits a position recalculation command message, by means of a DTMF signal.Type: ApplicationFiled: September 4, 2002Publication date: March 13, 2003Inventors: Yoshihiko Baba, Teruhide Kunimitsu, Kenji Sekine, Mikio Iwakuni, Katsuhiro Miyamoto, Toshiaki Yuasa, Toshihiro Takahashi, Norio Abe, Shuji Konishi, Tadashi Kogure, Jun Yoshida, Katsuya Kaneda, Isao Ohki, Masaru Akiyama, Masato Suzuki
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Publication number: 20030048132Abstract: To provide a small-sized high frequency power amplifier for preventing oscillation by a small number of switching circuits and outputting high power and low power with high efficiencies, a high frequency power amplifier module and a portable telephone, the high frequency power amplifier is constituted by an amplifying circuit A and an amplifying circuit B connected in parallel, a size of a transistor at an output stage of the amplifying circuit B is made to be equal to or smaller than ¼ of a size of a transistor of an output stage of the amplifying circuit A and a switching circuit is connected between a signal line forward from the output stage of the amplifying circuit A and a ground terminal.Type: ApplicationFiled: July 11, 2002Publication date: March 13, 2003Applicant: Hitachi, LtdInventors: Osamu Kagaya, Masami Ohnishi, Kenji Sekine, Tomonori Tanoue
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Publication number: 20030025555Abstract: The present invention provides a radio frequency power amplifier which may not introduce radio frequency loss during switching power amplifier units between high and low output power levels. By connecting a first-stage matching network M12 and first-stage matching network M13 to respective output nodes of a power amplifier unit A11 and power amplifier unit A12 that either one operate by switching, connecting the output nodes of the first-stage matching network M12 and M13 in parallel, connecting a last-stage matching network M11 between the junction of M12 and M13 and the output terminal OUT, the first-stage matching networks M12, M13, and last-stage matching network M11 are formed, for both power amplifier units A11 and A12, so that impedance matching is established between the output terminal OUT and the power amplifier unit in operation when one unit is in operation the other is in stop of operation.Type: ApplicationFiled: June 5, 2002Publication date: February 6, 2003Applicant: Hitachi, Ltd.Inventors: Masami Ohnishi, Hidetoshi Matsumoto, Tomonori Tanoue, Osamu Kagaya, Kenji Sekine
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Publication number: 20020196090Abstract: A microwave/millimeter wave band oscillator made up of a dielectric resonator 1, and a monolithic integrated circuit 2 including an oscillator circuit is configured as follows. In a metallic area 5 immediately under substrates 2 and 3 equipped with the dielectric resonator 1, there is provided air or a material 6 having a smaller permittivity than the permittivity of the dielectric resonator, having a thickness equal to, or more than the height of the dielectric resonator 1 in the direction immediately under the substrates, and a larger cross sectional area than the cross sectional area of the dielectric resonator.Type: ApplicationFiled: May 24, 2002Publication date: December 26, 2002Inventors: Naoyuki Kurita, Hiroshi Kondoh, Kenji Sekine
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Patent number: 6495914Abstract: A metal base substrate for mounting a plurality of bare semiconductor chip devices thereon has first and second main surfaces. The first main surface has formed thereon at least one projection, and at least two recesses in which the bare semiconductor chip devices are to be mounted. The depth of these recesses is smaller than the length of said projection, and the recesses have a higher surface smoothness than said main surfaces of said metal substrate. The metal base substrate is partially chemically etched to form the projection, and the first main surface of the substrate is mechanically worked to form at least the recesses. The conductive projection is isolated from the portion on which the bare semiconductor chip devices are mounted, of the base substrate, and the conductive projection acts as a terminal that can be electrically connected to the outside on the first and second main surfaces of the base substrate.Type: GrantFiled: February 10, 2000Date of Patent: December 17, 2002Assignee: Hitachi, Ltd.Inventors: Kenji Sekine, Hiroji Yamada, Matsuo Yamasaki, Osamu Kagaya, Kiichi Yamashita
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Patent number: 6489680Abstract: In a semiconductor device such as a high-frequency power amplifier module, a plurality of amplifying means are formed on a semiconductor chip which is mounted on a main surface of a wiring substrate, and electrodes of the semiconductor chip are electrically connected by wires to electrodes of the wiring substrate. In order to make the high-frequency power amplifier module small in size, a substrate-side bonding electrode electrically connected to a wire set at a fixed reference electric potential is place at a location farther from a side of the semiconductor chip than a substrate-side output electrode electrically connected to an output wire. A substrate-side input electrode electrically connected to an input wire is located at a distance from the side of the semiconductor chip about equal to the distance from the side of the semiconductor chip to the substrate-side output electrode, or at a location farther from the side of the semiconductor chip than the substrate-side bonding electrode is.Type: GrantFiled: October 5, 2001Date of Patent: December 3, 2002Assignees: Hitachi, Ltd., Hitachi Tohbu Semiconductor, Ltd.Inventors: Iwamichi Kohjiro, Yasuhiro Nunogawa, Sakae Kikuchi, Shizuo Kondo, Tetsuaki Adachi, Osamu Kagaya, Kenji Sekine, Eiichi Hase, Kiichi Yamashita
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Publication number: 20020115414Abstract: The present invention can achieve a completely sub-modularized apparatus, prevent frequency thereof from being fluctuated and reduce manufacturing cost thereof. The present invention has a RF oscillator apparatus whose frequency is set in advance and which is compactly sub-modularized; a transceiving module case which is a base substrate; a transceiving module upper cover which is a seal material covering an upper portion of a conductive wall of the RF oscillator apparatus; a RF circuit substrate which is a wiring substrate loading the RF oscillator apparatus and a receiving mixer and the like; and a bonding wire connecting the RF oscillator apparatus and the receiving mixer and the RF circuit substrate to each other.Type: ApplicationFiled: March 19, 2001Publication date: August 22, 2002Inventors: Kenji Sekine, Hiroshi Kondoh, Naoyuki Kurita
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Publication number: 20020089380Abstract: A radio frequency power amplifier module for a dual-band type mobile communication apparatus that can transmit and receive the first frequency f1 and the second frequency f2 (f2=2×f1) is structured as explained below.Type: ApplicationFiled: February 28, 2002Publication date: July 11, 2002Applicant: Hitachi, Ltd.Inventors: Toru Fujioka, Isao Yoshida, Mineo Katsueda, Masatoshi Morikawa, Yoshikuni Matsunaga, Kenji Sekine, Osamu Kagaya
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Publication number: 20020089373Abstract: A base station for a multi-carrier mobile communication system, which is equipped with an RF amplifier including input ports for inputting a plurality of input signals different in frequency of carrier from one another, dividers for respectively dividing each of the plurality of input signals inputted to the input ports into plural form, and phase shifters for respectively assigning a weight of phase to each of divided signals corresponding to a number obtained by subtracting 1 from the number of divisions. A plurality of first combiners are provided for respectively adding up the signals different in the frequency of carrier, out of the divided signals and signals each assigned the weight of phase, a plurality of amplifiers are provided for respectively amplifying signals outputted from the plurality of first combiners, and a second combiner is provided for adding signals outputted from the plurality of amplifiers to output one signal.Type: ApplicationFiled: February 6, 2002Publication date: July 11, 2002Inventors: Ken Takei, Kenji Sekine
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Publication number: 20020082045Abstract: In a mobile telephone apparatus corresponding to dual-band provided with an RF power module to operate in two kinds of different frequencies, a common harmonics control circuit is provided to the output circuit of such RF power module to realize higher efficiency in view of controlling respective harmonics power for both band frequencies. Moreover, a means for selectively setting the bias is also provided so that the maximum efficiency can be attained depending on the output power required with respective communication systems with the bias control signal output from the CPU of the control unit interlocking with selection of frequency of the mobile telephone apparatus body. In addition, a switching element is also provided to such harmonics control circuit to enable the harmonics control without giving any influence on the radio frequency signal of each communication system.Type: ApplicationFiled: February 5, 2002Publication date: June 27, 2002Inventors: Toru Fujioka, Isao Yoshida, Mineo Katsueda, Masatoshi Morikawa, Yoshikuni Matsunaga, Kenji Sekine, Osamu Kagaya
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Publication number: 20020067313Abstract: A high frequency communication device which can reduce undesired electromagnetic coupling inside and outside a box thereof in which circuit parts constituting a transmitter-receiver circuit are contained.Type: ApplicationFiled: January 4, 2002Publication date: June 6, 2002Inventors: Hiroshi Kondoh, Hiroshi Shinoda, Kenji Sekine
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Patent number: 6396349Abstract: A power combiner having a plurality of power amplifiers which are even-numbered, a plurality of series-connected branch circuits for respectively distributing input power to the plurality of power amplifiers, and a plurality of series-connected combiners for combining the respective output power of the plurality of power amplifiers. In the case of any one of such combinations as to equalize electric lengths of transmission lines for connecting between two power amplifiers selected from the plurality of power amplifiers, the combinations each being established by using all of the plurality of power amplifiers once, the electric lengths at which the any one of the combinations are established, take &lgr;/2i (where &lgr;=wavelength of fundamental wave, and i=positive integer).Type: GrantFiled: March 15, 2001Date of Patent: May 28, 2002Assignee: Hitachi, Ltd.Inventors: Ken Takei, Masami Ohnishi, Kenji Sekine
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Patent number: 6384688Abstract: A radio frequency power amplifier module for a dual-band type mobile communication apparatus that can transmit and receive the first frequency f1 and the second frequency f2 (f2=2×f1) is structured as explained below. This radio frequency power amplifier module for dual-band type mobile communication apparatus is comprised of a drive stage amplifier having the gain peaks at f1 and f2 with a matching circuit and a radio frequency power output circuit including a radio frequency power output transistor.Type: GrantFiled: October 25, 2000Date of Patent: May 7, 2002Assignee: Hitachi, Ltd.Inventors: Toru Fujioka, Isao Yoshida, Mineo Katsueda, Masatoshi Morikawa, Yoshikuni Matsunaga, Kenji Sekine, Osamu Kagaya
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Patent number: 6384680Abstract: The present invention aims to provide a RF amplifier capable of controlling the generation of spurious signals when plural carriers are simultaneously amplified. The RF amplifier includes dividers for respectively dividing each of a plurality of input signals different in frequency of carrier from one another into plural form, phase shifters for respectively assigning weights to phases every divided signals corresponding to a number obtained by subtracting 1 from the divided plural numbers, first combiners for adding up the signals different in the frequency of carrier, of the divided signals and the signals subjected to the phase weighting, amplifiers for respectively amplifying signals outputted from the first combiners, and a second combiner for adding the signals outputted from the amplifiers together to thereby output one signal from the second combiner. Spurious signal components are canceled out by addition of the output signals of the amplifiers.Type: GrantFiled: August 16, 2000Date of Patent: May 7, 2002Assignee: Hitachi, Ltd.Inventors: Ken Takei, Kenji Sekine
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Patent number: 6366788Abstract: In a mobile telephone apparatus corresponding to dual-band provided with an RF power module to operate in two kinds of different frequencies, a common harmonics control circuit is provided to the output circuit of such RF power module to realize higher efficiency in view of controlling respective harmonics power for both band frequencies. Moreover, a means for selectively setting the bias is also provided so that the maximum efficiency can be attained depending on the output power required with respective communication systems with the bias control signal output from the CPU of the control unit interlocking with selection of frequency of the mobile telephone apparatus body.Type: GrantFiled: October 26, 2000Date of Patent: April 2, 2002Assignee: Hitachi, Ltd.Inventors: Toru Fujioka, Isao Yoshida, Mineo Katsueda, Masatoshi Morikawa, Yoshikuni Matsunaga, Kenji Sekine, Osamu Kagaya
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Publication number: 20020024390Abstract: There is provided a power amplifier module which is provided with a function of protecting an amplifying device against destruction caused by a standing wave by reflection from an antenna end in load variation, having a high tolerance level of device destruction and is highly efficient.Type: ApplicationFiled: August 20, 2001Publication date: February 28, 2002Applicant: Hitachi, Ltd.Inventors: Kiichi Yamashita, Tomonori Tanoue, Isao Ohbu, Kenji Sekine
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Publication number: 20020015291Abstract: In a semiconductor device such as a high-frequency power amplifier module, a plurality of amplifying means are formed on a semiconductor chip which is mounted on a main surface of a wiring substrate, and electrodes of the semiconductor chip are electrically connected by wires to electrodes of the wiring substrate. In order to make the high-frequency power amplifier module small in size, a substrate-side bonding electrode electrically connected to a wire set at a fixed reference electric potential is placed at a location farther from a side of the semiconductor chip than a substrate-side output electrode electrically connected to an output wire. A substrate-side input electrode electrically connected to an input wire is located at a distance from the side of the semiconductor chip about equal to the distance from the side of the semiconductor chip to the substrate-side output electrode, or at a location farther from the side of the semiconductor chip than the substrate-side bonding electrode is.Type: ApplicationFiled: October 5, 2001Publication date: February 7, 2002Applicant: Hitachi, Ltd.Inventors: Iwamichi Kohjiro, Yasuhiro Nunogawa, Sakae Kikuchi, Shizuo Kondo, Tetsuaki Adachi, Osamu Kagaya, Kenji Sekine, Eiichi Hase, Kiichi Yamashita
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Publication number: 20020006778Abstract: The present invention can achieve a completely sub-modularized apparatus, prevent frequency thereof from being fluctuated and reduce manufacturing cost thereof. The present invention has a RF oscillator apparatus whose frequency is set in advance and which is compactly sub-modularized; a transceiving module case which is a base substrate; a transceiving module upper cover which is a seal material covering an upper portion of a conductive wall of the RF oscillator apparatus; a RF circuit substrate which is a wiring substrate loading the RF oscillator apparatus and a receiving mixer and the like; and a bonding wire connecting the RF oscillator apparatus and the receiving mixer and the RF circuit substrate to each other.Type: ApplicationFiled: March 19, 2001Publication date: January 17, 2002Inventors: Kenji Sekine, Hiroshi Kondoh, Naoyuki Kurita