公开(公告)号：JPH0727797A

公开(公告)日：1995-01-31

申请号：JP19308793

申请日：1993-07-08

Applicant: ADVANTEST CORP

Inventor： MORI EIJI ,  UEKI YUTAKA

IPC: G01R23/173 ,  G01R35/00

Abstract: PURPOSE:To easily perform a correction operation, to eliminate a tracking error clue to a change in ambient temperature and to perform a stable measurement by a method wherein an oscillator is swept, a calibrating operation is performed and the center frequency of an IF filter is found by a control part. CONSTITUTION:The automatic correction circuit is constituted of a synthesizer 13, a variable oscillator 21, mixers 12, 15, 20, a fixed oscillator 17, a switch 14, an attenuator 16, a BPF 16 and a control part 23. Then, in a calibrating operation to find a center frequency, the switch 14 is changed over to the side of a tracking generator (TG) in advance, the oscillator 21 is swept, and the level of an output 34 at every sweep frequency is read out. As a result, the frequency of a maximum output level point is found. The frequency is found as an IF center frequency at a present ambient temperature and in a present apparatus state. The center frequency which has been found is set in the oscillator 21, the switch 14 is returned to the side of a measurement, and the calibrating operation is completed.

公开(公告)号：JPH0720169A

公开(公告)日：1995-01-24

申请号：JP21681593

申请日：1993-06-29

Applicant: ADVANTEST CORP

Inventor： MORI EIJI

IPC: G01R23/173

Abstract: PURPOSE:To eliminate a signal source which is leaked to the side of an IF part and to measure a weak signal by a method wherein two oscillators are installed, they are mixed and a required TG (tracking-generator) output frequency is obtained. CONSTITUTION:This constitution is provided with a synthesizer 14 which sweeps a frequency and with a mixer 12 which mixes the synthesizer 14 with a received signal. In addition, mixers 18, 16 which mix the synthesizer 14 with fixed oscillators 19, 17 on the side of a TG, and a filter 23 which traps an unwanted frequency is installed.

公开(公告)号：JPH07283621A

公开(公告)日：1995-10-27

申请号：JP9567994

申请日：1994-04-08

Applicant: ADVANTEST CORP

Inventor： MORI EIJI

IPC: H01P5/18

Abstract: PURPOSE:To improve the direction characteristic by providing a triangular taper punched pattern in a part of an earth conductor just under the rear face of a coupler line to reduce the difference of the effective dielectric constant changed between even mode propagation and odd mode propagation. CONSTITUTION:A triangular taper punched pattern 21a is provided in a part of the earth conductor just under the rear face of a coupler line 21. When a frequency characteristic will be given to the coupler, wavy or arcuate projections are formed in sides of the trinagle of the punched pattern 21a. Thus, the difference of the effective dielectric constant between even mode propagation and odd mode propagation is reduced to obtain a directional characteristic.

公开(公告)号：JPH07244097A

公开(公告)日：1995-09-19

申请号：JP6007994

申请日：1994-03-04

Applicant: ADVANTEST CORP

Inventor： MUSHA HIROBUMI ,  SAKUMA HIROSHI ,  TANABE TAKESHI ,  MORI EIJI

IPC: G01R27/06 ,  G01R23/173 ,  G01R27/28

Abstract: PURPOSE:To eliminate an external test jig and to measure a spectrum with one external signal generator by incorporating a signal generating function of one channel and a synthesizer and measuring a cross modulation distortion. CONSTITUTION:A cross modulation distortion is measured by connecting an external signal generator 127 for generating a first frequency signal, the spectrum analyzer 140, and two frequency signals to a unit DUT 110 to be tested. An SG input terminal 21, a third switch 13, an output frequency of a tracking generator TG for generating a second frequency signal, an SWR bridge 24 and a fourth switch 14 are used in the analyzer 140, which combines the two frequency signals and outputs it to a TG output terminal 26. A first frequency signal f41 to be input from the generator 127 is coupled to a TG output line by the bridge 24 via the switch 13, and then terminated at a terminating resistor R25. Generation of a cross modulation at an output point of the TG is prevented by the bridge 24, and a measuring function of the cross modulation distortion is realized.

公开(公告)号：JPH07240665A

公开(公告)日：1995-09-12

申请号：JP5272394

申请日：1994-02-25

Applicant: ADVANTEST CORP

Inventor： MUSHA HIROBUMI ,  SAKUMA HIROSHI ,  TANABE TAKESHI ,  MORI EIJI

IPC: H03H11/24

Abstract: PURPOSE:To realize an attenuator of a super high frequency where prescribed input/output impedance is maintained and a necessary variable range is wide. CONSTITUTION:This attenuator has constitution means where a first matching pad 12 matching d the input impedance of an input terminal is provided; a transistor 14 receiving signal from the first matching pad 12 and amplifying it is provided; a resistor R 15 for load is provided on the side of the output of the transistor 14 and is connected, a control circuit 13 which is capable of an output current value or an output voltage value by an external control signal 13a is provided; the output terminal of the control circuit 13 is connected with the other terminal of the resistance R 15 for load; a capacitor C 21 cutting the DC components is provided on the side of the output of the transistor 14;' and a second matching pad 16 receiving the output signal from the capacitor C 21 and taking the matching of the output impedance is provided.

公开(公告)号：JPH085681A

公开(公告)日：1996-01-12

申请号：JP16320194

申请日：1994-06-22

Applicant: ADVANTEST CORP

Inventor： MORI EIJI ,  KAMOSAKI KEIGO

IPC: G01R23/173 ,  H03D7/00 ,  H04B1/26

Abstract: PURPOSE:To remove the mixer communication signal from a local oscillator significantly from the output signal of a mixer by providing a variable phase shifter, a variable attenuator, a directional coupler, and a control section. CONSTITUTION:A variable phase shifter 10 outputs the signal from a local oscillator 50 while shifting the phase thus forming a phase angle reverse to that of a mixer communication signal 50a. The phase shifter 10, a variable attenuator 20 and a directional coupler 30 synthesize an inverted signal of the mixer communication signal 50a thus canceling the disturbance signal 50a selectively. A control section 40 receives a frequency setting data signal of sweep step frequency being delivered from a ramp voltage generating section 51 to the oscillator 50. A phase angle data corresponding to the frequency and an attenuation value data are then read out from a parameter memory 42. The data is delivered to corresponding phase shifter 10 and attenuator 20 in order to cancel the signal 50a. When the intermediate frequency f110 is close to the oscillation frequency f100 of the oscillator 50, the signal 50a is canceled thus eliminating the effect of the oscillator 50.

公开(公告)号：JPH07306234A

公开(公告)日：1995-11-21

申请号：JP12069794

申请日：1994-05-10

Applicant: ADVANTEST CORP

Inventor： MIYAUCHI YASUSHI ,  KAMOSAKI KEIGO ,  MORI EIJI

IPC: G01R27/28 ,  G01R23/173

Abstract: PURPOSE:To measure the transmission characteristics of a remote DUT easily by separating a tracking generator section from a spectrum analyzer and feeding a TG(tracking generator) signal to the remote DUT. CONSTITUTION:A tracking frequency signal fTG is outputted while being given a signal for sweep synchronization at the time prior to a sweep signal for measuring DUT. A TG generator 200 comprises a TG receiving section 262, a carrier frequency detecting section 276, a decode executing section 280, and a TG feeding section 220. A spectrum measuring apparatus 300 comprises a frequency converting section 310, a synchronizing timing detecting section 350, a measurement executing section 370, and a parameter transmitting section 360. Measurement is performed while maintaining the synchronism of reference oscillation source and sweeping between them.

公开(公告)号：JPH07283679A

公开(公告)日：1995-10-27

申请号：JP8741194

申请日：1994-04-04

Applicant: ADVANTEST CORP

Inventor： MORI EIJI ,  MUSHA HIROBUMI

IPC: H01P1/20 ,  H03H7/075

Abstract: PURPOSE:To improve a high frequency attenuation characteristic by forming the inductance element composing a concentrated constant type LPF by the conductor patterns provided on the both surfaces of a printed board and the through hole connecting these patterns. CONSTITUTION:On the upper surface of a printed board 90, wiring patterns 51, 52,..., are provided, and on the lower surface, connection patterns 11c, 12c,... are provided. The coil part of a microstrip line is formed by successively connecting the wiring pattern 51, the connection pattern 11c, the wiring pattern 52 and the connection pattern 12c,... by through holes 11a, 11b and 12a,.... A pi type concentrated constant LPF is composed by connecting chip capacitors 71, 72,... between the wiring patterns 51, 52,... and a ground conductor 95. By properly selecting the lengths of the connection pattern 11c,... and the diameters of the through holes 11a,..., the inductance of a coil is set to a desired value. The shield between filter steps by a shield plate 21 is excellent. The dispersion of the inductance of each coil is small.

公开(公告)号：JPH07260852A

公开(公告)日：1995-10-13

申请号：JP7952994

申请日：1994-03-25

Applicant: ADVANTEST CORP

Inventor： MUSHA HIROBUMI ,  SAKUMA HIROSHI ,  TANABE TAKESHI ,  MORI EIJI

IPC: G01R27/28 ,  G01R23/173

Abstract: PURPOSE:To realize highly accurate direct measurement of the transmission characteristics and the level of a DUT by outputting a frequency obtained by adding or subtracting an arbitrary offset frequency to or from the output frequency of a tracking generator(TG). CONSTITUTION:A synthesizer 10 receives a frequency signal f71a from a reference oscillator 71 and delivers a reference frequency signal fREF to a first frequency divider 82. A TG oscillating section 80 receives a signal from the synthesizer 10 along with a sweep frequency signal f73a from a spectrum measuring section 40 and delivers a frequency for imparting a TG output frequency synchronous with a receiving input frequency (fin), a frequency fTG provided with an arbitrary offset frequency in synchronism with the frequency (fin), and a frequency fTG independent from the frequency (fin). The signal f71a and a signal from the oscillating section 80 are subjected to frequency conversion at a TG section 90 and fed to a TG output terminal 26.