公开(公告)号：JPH0554622A

公开(公告)日：1993-03-05

申请号：JP23543591

申请日：1991-08-22

Applicant: NEC CORP

Inventor： FUKUDA JUNICHI

IPC: G11B5/02 ,  G11B33/12

Abstract: PURPOSE:To make a manufacture easy with a simple construction, to easily connect to a magnetic head, to efficiently prevent the generation of noise due to an interference of a serve signal and data signal, and also to increase durability of the whole circuit. CONSTITUTION:This circuit is provided with a data signal outputting circuit 3 to transmit the data signal into the magnetic head for data (magnetic head 7), servo signal outputting circuit 4 to transmit the servo signal into the magnetic head 7, and [FPC] 1A as a main body of planar circuit furnished with these circuits 3, 4. Then, the data signal outputting circuit 3 is equiped on one side 1B of the FPC 1A and also the servo signal outputting circuit 4 is equiped on another side 1C, and a shield pattern 12 is laid between these one side and another side surfaces 1B, 1C each other.

公开(公告)号：JPH0258769A

公开(公告)日：1990-02-27

申请号：JP20814988

申请日：1988-08-24

Applicant: NEC CORP

Inventor： FUKUDA JUNICHI

IPC: G11B20/10

Abstract: PURPOSE:To perform data writing and readout under the optimum conditions by switching writing timing correcting quantities corresponding to the short- circuited or released state of an identification short-circuiting plug. CONSTITUTION:The head disk assembly (HDA) identifying signal 102 of a HDA 10 is outputted to a detection circuit 20 and the control signal 103 of the circuit 20 is outputted to a write circuit 30 and inputted to the HDA 10. The write circuit 30 inputs write data 100 and write clocks 101 and is composed of a pattern decoder 31, delay circuit 32, selector 33, and driver 34 connected in series. The control signal 103 from the detection circuit 20 is inputted to the selector 33. By controlling the selector 33 of the write circuit 30 with the control signal 103, writing timing correcting quantities are switched. Therefore, data writing and readout can be performed under the optimum conditions.

公开(公告)号：JP2000149462A

公开(公告)日：2000-05-30

申请号：JP32424898

申请日：1998-11-13

Applicant: NEC CORP

Inventor： FUKUDA JUNICHI

IPC: G11B20/18 ,  G11B19/04

Abstract: PROBLEM TO BE SOLVED: To provide a disk device that can enhance the error recovery perfor mance by an error recovery means performed on the occurrence of an error, and also can shorten the error recovery processing time. SOLUTION: An error recovery condition having high error recovery effect is selected from error occurrence conditions and a judging result of a cause of an error (step S1), and recovery means are performed from an error recovery means having a high error recovery rate out of selected error recovery means (step S2). After performing error recovery processing, by preserving an error recovery processing result (step 8), the priority of performing an error recovery means having high error recovery effect is made high and the priority of performing an error recovery means having low error recovery effect is made low, next, when error recovery processing is performed in the same condition, it is performed from an error recovery means having high error recovery effect.

公开(公告)号：JPH11219504A

公开(公告)日：1999-08-10

申请号：JP3373798

申请日：1998-01-30

Applicant: NEC CORP

Inventor： FUKUDA JUNICHI

IPC: G11B5/09

Abstract: PROBLEM TO BE SOLVED: To prevent the occurrence of damage in a magnetic disk device so as to improve the reliability of the device by monitoring the signal quality of the magnetic disk device and detecting the possible occurrence of damage in the magnetic disk device without adding any special hardware. SOLUTION: In a magnetic disk device for sampling the output waveforms of a magnetic head which reads data from a magnetic disk, converting these into digital data and then demodulating the data, an arithmetic processing unit 21 is provided for calculating an average value and standard deviation among specified sampling points of the sampled data, or the average value and standard deviation of the difference of expected values among the sampling points.

公开(公告)号：JPH1166509A

公开(公告)日：1999-03-09

申请号：JP22335897

申请日：1997-08-20

Applicant: NEC CORP

Inventor： FUKUDA JUNICHI

IPC: G11B5/09 ,  G11B5/02 ,  G11B5/39 ,  G11B21/10

Abstract: PROBLEM TO BE SOLVED: To provide a magnetic recording apparatus in which a sense current capable of enhancing a performance most in terms of an apparatus performance is determined by a simple method in terms of the apparatus and in which a write offset value and a read offset value can be determined. SOLUTION: A signal which is read out by a magnetoresistance effect-type (MR) head 1 is demodulated by a read/write circuit 2 and a data modulation/ demodulation circuit 3. Servo information is demodulated by a servo signal modulation circuit and a positioning control circuit 4. A microcomputer 6 changes a sense current, it detects the read error of a data part on a magnetic disk and the error of a servo part, and it determines an optimum sense current value. The microcomputer 6 offsets the MR head 1 to the track direction of the magnetic disk, it detects an error, and it determines the write offset value and the read offset value of the MR head 1.

公开(公告)号：JPH03280204A

公开(公告)日：1991-12-11

申请号：JP7929190

申请日：1990-03-28

Applicant: NEC CORP

Inventor： FUKUDA JUNICHI

IPC: G11B5/09

Abstract: PURPOSE:To improve the reliability of read data without losing interchangeability by arranging a pair of identification (ID) pins in a head disk assembly (HDA) and switching a waveform correcting value in accordance with the short- circuited/opened state of the ID pins. CONSTITUTION:A pair of ID pins P1, P2 whose short-circuited/opened state can be operated from the external are arranged in the HDA 10. An HDA ID signal 102 is formed in accordance with the short-circuited states of the pins P1, P2. When respective pins P1,P2 are in their opened states, a detection circuit 20 outputs a control signal 103, the opened/closed states of respective switches 43, 44 in a waveform correcting circuit 40 are switched by the control signal 103 to adjust the waveform correcting value. Even when rot variation is generated in a magnetic head or a magnetic disk, a waveform can be corrected by the proper correction value without losing interchangeability between the HDA and the magnetic disk device.

公开(公告)号：JPH03237661A

公开(公告)日：1991-10-23

申请号：JP3288590

申请日：1990-02-13

Applicant: NEC CORP

Inventor： FUKUDA JUNICHI

IPC: G11B20/14

Abstract: PURPOSE:To reduce that real data subsequent to the reference peak pulse string of a prescribed period to be miread or it cannot be read by providing a filter having two filter parts and switching two filter parts in accordance with the types of data inputted from a data storage part at the time of reproducing data. CONSTITUTION:In the filter 3, the filter parts 31 and 32 are set to be low pass filters and the filter part 31 is set to be a filter for real data, whereby the filter part 32 is set to be a filter for the reference data string of the prescribed period for phase matching. Two filter parts 31 and 32 are switched by the filter switching signal 106 being the output of a read control circuit 6 in accordance with the types of data inputted from a head disk assembly (HDA) 1 beidng the data storage part. Thus, it is reduced that real data subsequent to reference data of the prescribed period is miread or it cannot be read.

公开(公告)号：JP2006148728A

公开(公告)日：2006-06-08

申请号：JP2004338265

申请日：2004-11-24

Applicant: Nec Corp ,  日本電気株式会社

Inventor： FUKUDA JUNICHI

IPC: H01Q13/08

CPC classification number: H01Q3/26 ,  H01Q1/243 ,  H01Q9/0421 ,  H01Q21/20

Abstract: PROBLEM TO BE SOLVED: To provide an antenna system which enables the directivity thereof to be controlled and can be small-sized.
SOLUTION: An antenna body 1 includes: an antenna element 11 of an upper layer; a ground part (ground) 12 of a lower layer; a dielectric 13 held by the antenna element 11 and the ground part 12; a columnar conductor (center post) 14 connecting the center of the antenna element 11 and the center of the ground part 12; and three power feeding conductors 16 (16-1 to 16-3) provided at power feeding points 15-1 to 15-3 on the same circumference respectively and connected with the antenna element 11. The antenna body 1 is disk-shaped as a whole and feeds signals of at least different amplitudes or phases to the power feeding points 15-1 to 15-3.
COPYRIGHT: (C)2006,JPO&NCIPI

Abstract translation: 要解决的问题：提供能够控制其指向性并且可以小型化的天线系统。 解决方案：天线体1包括：上层的天线元件11; 下层的接地部分（接地）12; 由天线元件11和接地部分12保持的电介质13; 连接天线元件11的中心和接地部12的中心的柱状导体（中心柱）14; 以及分别设置在同一圆周上的供电点15-1至15-3处并与天线元件11连接的三个馈电导体16（16-1至16-3）。天线体1是盘形的， 将至少不同幅度或相位的信号馈送到馈电点15-1至15-3。 版权所有（C）2006，JPO＆NCIPI

公开(公告)号：JP2003243927A

公开(公告)日：2003-08-29

申请号：JP2002042431

申请日：2002-02-20

Applicant: NEC CORP

Inventor： FUKUDA JUNICHI

IPC: H01Q19/32 ,  H01Q3/44 ,  H01Q5/10 ,  H01Q9/30 ,  H01Q5/01

Abstract: PROBLEM TO BE SOLVED: To reduce the reflection coefficient to ensure a practical band in an antenna system having auxiliary antennas arranged around a main antenna so as to control the directivity. SOLUTION: A main antenna 1 is provided with two main antenna elements 11, 12 whose length differs from each other and placed adjacent to each other in order to respectively secure transmission/reception bands. One of the elements of the main antenna is resonated at the reception frequency and the other is resonated at the transmission frequency. Further, the shape (length) of the main antenna and the auxiliary antennas 201 to 206 is decided such that the reflection coefficient of antenna input has a prescribed value (ordinarily 2) or below, in particular, such that the distribution of antenna input impedance with respect to the phase shift conditions of the auxiliary antennas is centered around the values of signal supply impedance. Thus, the phase shift conditions capable of securing a practical band can remarkably be increased and various directivity patterns can be obtained. COPYRIGHT: (C)2003,JPO

公开(公告)号：JP2002353867A

公开(公告)日：2002-12-06

申请号：JP2001154505

申请日：2001-05-23

Applicant: NEC CORP

Inventor： FUKUDA JUNICHI

IPC: H01Q3/24 ,  H01Q21/20 ,  H04B7/10 ,  H04B7/26

Abstract: PROBLEM TO BE SOLVED: To control an optimum antenna directivity pattern at reception and transmission with a comparatively simple method in an information terminal provided with a variable directivity antenna. SOLUTION: A processing circuit for the information terminal provided with a variable directivity antenna sequentially transmits only a directivity pattern having a unidirectional directivity among the finite number of directivity data taken by the variable directivity antenna to a control circuit to conduct directivity scanning and to decide reception signal quality by each directivity. The processing circuit decides an optimum directivity pattern from the scanning decision result and transmits directivity data including a reception frequency to the control circuit at reception and transmits directivity data including a transmission frequency to the control circuit at transmission. The control circuit controls the variable directivity antenna so as to obtain the optimum directivity pattern for the reception frequency and the transmission frequency.