baber/WOPTO huggingface dataset:
Patent KR-20010053979-A (KR)
Inventor: CHO KYOUG YOUN
IPC: F25B41/00
Filed: 1999-12-02
Abstract: PURPOSE: A heat exchanger for freezer and freezer apparatus adopting such heat exchanger is provided to improve performance and durability of compressor by preventing ingress of wet saturated steam into the compressor, and improve freezing performance of the freezer by cooling the refrigerant flowing into the expansion valve. CONSTITUTION: A heat exchanger comprises a shell where the refrigerant introduced from an evaporator is divided into a gaseous phase and a liquid phase; an inlet tube(16) for ingress of the refrigerant discharged from the evaporator; a gaseous phase refrigerant discharge tube(17) for discharging the gaseous phase refrigerant from the shell interior into a compressor; heat exchange tubes(13,14) for supplying heat to the liquid refrigerant existing within the shell so as to vaporize the liquid refrigerant. The heat exchanger serves to divide the refrigerant flowing from the evaporator into a saturated liquid and saturated steam. Since the refrigerant discharged from the evaporator is at a wet saturated steam state, the refrigerant is introduced into the shell through the inlet tube. Part of the wet saturated steam discharged from the evaporator turns into a dry saturated steam due to the low pressure of the shell, and the residual part of the wet saturated steam turns into a liquid phase, thus allowing the refrigerant to be divided into gaseous phase and liquid phase. The liquid phase refrigerant is heat exchanged with the refrigerant at the saturated steam state, and the saturated liquid refrigerant turns into the dry saturated state. The refrigerant introduced through the tube(13) is cooled and flows into the expansion valve through the tube(14). The saturated liquid and the refrigerant at the wet saturated steam state in the shell transfers heat to the high temperature refrigerant flowing from the liquid receiver, turns into a dry saturated steam, and enters the compressor after being discharged through the refrigerant discharge tube.
Patent KR-20000012513-A (KR)
Inventor: OH SUNG TAEK
IPC: H04R1/02
Filed: 1999-12-09
Abstract: PURPOSE: A desk frame speaker is provided to keep a many kinds of pictures, photographs or illustrations at a side of speaker and to improve an ability of application by diminishing the volume. CONSTITUTION: The desk frame speaker comprises a whooper box(12), main panel(30), back panel(40) and front panel(50). An accommodation space(10) is formed inside of the whooper box(12) and plurals of first sound output hole(14) and second sound output hole(16) are formed at bottom of the front and center part of the accommodation space(10). A cone speaker(18) making a right and left sound is fixed at the bottom of the front of the accommodation space(10), and an amplifying circuit board unit(22) connected the cone speaker(18) and the cone speaker(20) for whooper is consisted in the upper part of the accommodation space(10). The main panel(30) is selectively connected to the whooper box(12) by adding cable, and connecting hole(32) is formed at each edge of the main panel, and a cutting part(34) is formed at the center of the main panel, and a thin board speaker(36) is fixed at the main panel. The back panel(40) is closely fixed to the other side of the main panel by conventional connecting mean. And, the front panel(50) is formed of same shape with the main panel(30) and having an accommodation groove(53) and connection bump(54).
Patent KR-20000048169-A (KR)
Inventor: ROIFLLER STEPHENE
IPC: G11C16/06
Filed: 1999-12-16
Abstract: PURPOSE: An output buffer and an adjusting method thereof are provided to actively adjust the strength of a drive according to the pattern of data output from the array of an adjacent output buffer. CONSTITUTION: To adjust a driver strength for an output buffer(50), the output buffer includes first and second driver circuits(56), inputs, and an adjusting circuit(54). The first driver circuit combines a first voltage to an output(52) in case of turning on. The second driver circuit combines a second voltage to the output in case of turning on. The inputs are combined to the first and the second driver circuits for turning on/off the driver circuits according to a first input signal. And, the adjusting circuit is combined to first and second driver devices for adjusting the strengths of the driver circuits according to data pattern. The data pattern includes the input signals of the output buffers. The output buffers input the first input signal and the data pattern to the adjusting circuit while adjusting the strengths of the driver circuits. Herein, the strengths of the driver circuits are adjusted according to high and low bits of the data pattern.
Patent KR-20000012691-A (KR)
Inventor: YOON BYUNG JOO
IPC: A01G1/04
Filed: 1999-12-18
Abstract: PURPOSE: The artificial cultivating system is provided to automate all the processes from production of compost for a mushroom to a mushroom cultivation. CONSTITUTION: The artificial cultivating system of a mushroom comprises:a laminated cultivator(100) for cultivating a mushroom; a drawer type cultivation table(10) arranged a culture medium mixed/inoculated inoculum; a culture medium granular device(20) for filling the culture medium of inoculum planting type by receiving the cultivation table(10); a mushroom bed delivering trolley(30) for loading a drawer type cultivation table(10) filled with the culture medium planted the inoculum in the culture medium granular device(20); an elevator(40) for moving the mushroom bed deliver trolley(30) to a cultivation room(130); an alarm(290).
Patent KR-20010057193-A (KR)
Inventor: HWANG GEUN JAE
IPC: F24C7/00
Filed: 1999-12-20
Abstract: PURPOSE: A built-in microwave oven is provided to efficiently form airflows in a microwave oven by restraining the generation of swirls or counterflows around a ventilating motor. CONSTITUTION: A built-in microwave oven includes an air intake grill(10) installed in the front upper portion of a microwave oven, a ventilation grill(20) installed in the front lower portion of the microwave oven, a sidewall passage(22a) formed on one face of the microwave oven to guide some of sucked air to the ventilation grill, a ventilating motor installed in the side upper portion of the microwave oven to form downward airflows toward the sidewall passage, and a shut-off plate(50) installed on the front face of the ventilating motor excepting the position of a discharge port(22c) to divide the ventilating motor from the sidewall passage. Herein, the shut-off plate prevents the generation of swirls or counterflows in the area of the ventilating motor. Therefore, smooth airflows are formed in the microwave oven.
Patent KR-20010064850-A (KR)
Inventor: KWAK JAE HYEON
IPC: C21D8/02
Filed: 1999-12-20
Abstract: PURPOSE: A process for preparing the subject steel sheet having a degree of quenching of T5 to T6 and drawing of 25% or more by annealing a thicker steel plate in a continuous annealing line and temper rolling is provided, thereby producing a high processing type steel sheet without flange processing cracks in high productivity. CONSTITUTION: This high strength extremely thin steel sheet is prepared by the following process consisting of: hot rolling low carbon aluminium killed steel comprising by weight, C:0.04 to 0.07%, Mn:0.4 to 0.6%, N:0.006 to 0.012% and the balance Fe with inevitable impurities; winding at 600deg.C or less; acid washing and cold rolling with a reduction ratio of 84 to 87%, continuously annealing in the temperature range of recrystallization temperature to 650deg.C and temper rolling with a reduction ratio of 5 to 10%.
Patent KR-20010057321-A (KR)
Inventor: OH BYEONG TAEK
IPC: B60J5/00
Filed: 1999-12-21
Abstract: PURPOSE: A vehicle door switch automatic holding device and the method thereof prevents an accident due to the wrong operation of a switch by automatically holding a vehicle door switch by a simple key manipulation. CONSTITUTION: A micro-computer decides whether a mirror selection switch signal for automatically holding the door switch of a vehicle is inputted or not. If the selection signal is inputted, the micro-computer decides whether a reverse gear is inputted or not. If the reverse gear is inputted, the micro-computer decides whether the reverse speed of the vehicle is higher than a predetermined speed or not. If the reverse speed of the vehicle is higher than a predetermined speed, the micro-computer automatically holds the door switch of the vehicle. Therefore, an accident due to the wrong operation of a switch is prevented.
Patent KR-20010061471-A (KR)
Inventor: KWON O WON
IPC: G11C16/06
Filed: 1999-12-28
Abstract: PURPOSE: A bit line clamp circuit of a flash memory is provided to improve the reliability and the read speed of a cell by discharging all bit lines to a ground in the time of the change of a standby and an address. CONSTITUTION: In a clamp circuit of redundant cells, NMOS transistors(N1 - N8) are connected to a sense amp(20) by being connected to a global signal line through an NMOS transistor(N9). At this time, the NMOS transistor(N9) is enabled by a sector selection address(SECY<0>). NMOS transistors(N10,N11) are connected between a ground and the global signal line. At this time, the NMOS transistors(N10) is enabled by RCLAMPON, and the NMOS transistors(N11) is enabled by DISCARR. In a clamp circuit of main cells, each NMOS transistor(M0N0 - M0N3) is enabled by a combination of the SECY<0> and an YSA<0:3>. Each NMOS transistor(M0N0 - M0N3) is connected to a global bit line, and the global bit line is connected to an IO sense amp(30) through an NMOS transistor(M0N5). An NMOS transistor(M0N4) is connected between the global bit line and the ground. At this time, the NMOS transistor(M0N4) is enabled by anBLC<0>, and is a clamping transistor.
Patent KR-20010061574-A (KR)
Inventor: KIM HYEON TAE
IPC: C25D3/00
Filed: 1999-12-28
Abstract: PURPOSE: A process for preparing the titled alloy steel sheet by adding ammonium chloride and a mixture of sodium salt condensed naphthalene sulfonic acid, sodium sulfate and o-vanillin as an additive to a basic solution is provided. Whereby, the Zn-Ni alloy plated steel sheet has excellent plating layer roughness, adhesion and processability. CONSTITUTION: In a process for producing Zn-Ni alloy plated steel sheet by electroplating under conditions of 0.5 to 2.0 molar concentration of a zinc ion, 0.1 to 0.5 molar concentration of nickel ion, 6.0 to 9.0 molar concentration of a chloride ion, a pH of a plating solution of 2.5 to 4.5, a temperature of the plating solution of 55 to 75deg.C, a current density of 40 to 180A/dm¬2 and a relative speed between the plating solution and the cathode of 0.5 to 2.5m/sec, the ammonium ion of the plating solution is maintained in a concentration of 0.1 to 0.5 mol and a plating solution obtained by adding 0.05 to 5.0g/L o-vanillin to a basic solution is used.
Patent KR-20010061894-A (KR)
Inventor: LIM SEON BAE
IPC: H04B7/26
Filed: 1999-12-29
Abstract: PURPOSE: A handover method from a third generation(3G) direct sequence(DS) system to a second generation(2G) or a third generation(3G) synchronization system is provided to effectively support a handover in an operation harmonization group(OHG) environment obtaining a system synchronization required for handover from 3G DS system cell to 2G or 3G synchronization system cell and identifying a target base station. CONSTITUTION: A user terminal(UE) reports an intensity of a receiving power to a radio network controller(RNC) periodically or upon request(2-1). The RNC determines whether a handover is to be performed and a type of the handover(2-2). In case of handover to a 2G synchronization system, the RNC broadcasts information on an adjacent cell(2-3). The user terminal(UE) obtains a system synchronization of the adjacent 2G cell by using a compression mode of a 3G DS of the system information of the adjacent 2G cell(2-4). The user terminal(E) informs the RNC of the system information of the adjacent cell obtained by synchronization, to request a channel establishment to a target base station(2-5). The RNC completes a channel establishing to the target base station and transmits a handover instruction to the user terminal(UE)(2-6). The UE informs the RNC of the response to the handover instruction, that is initiation of handover(2-7). When handover is completed, the UE informs the target base station of it(2-8), and the target base station informs an MSC that handover has been completed for a radio interval(2-9). The MSC requests the FNC to release a resource allocated to a call(2-10). The RNC informs the MSC that the resource has been released for the corresponding call(2-11).
Patent KR-20010064639-A (KR)
Inventor: KIM JEONG SEONG
IPC: G01N3/08
Filed: 1999-12-29
Abstract: PURPOSE: A movable spot welded test piece tension tester is provided to reduce weight of the tester by making a main body of the tester of aluminum alloy and be used semipermanently. CONSTITUTION: A movable spot welded test piece tension tester includes a tension measuring/displaying unit(20) fixedly installed on one side of a main body(10) of the tester and formed with a load cell(22) and an indicator(24) electrically connected with the load cell, a tension generating unit(40) fixedly installed on the other side of the main body of the tester and operated by a hydraulic pump(49) for generating tension, and a second test piece fixing unit(50) fixedly installed on one side of the tension generating unit to be opposite to a first test piece fixing unit(30) and fixing the other side of the spot welded test piece(60).
Patent KR-20010058945-A (KR)
Inventor: CHOI BYEONG DAE
IPC: H01L21/76
Filed: 1999-12-30
Abstract: PURPOSE: A method for forming an isolation layer is to improve the characteristic and reliability of a semiconductor device. CONSTITUTION: A pad oxide layer is formed on a semiconductor substrate(11) at the thickness of 30 to 300 angstroms by using a thermal oxidization process. A pad nitride layer is formed on the pad oxide layer at the thickness of 500 to 3000 angstroms. A trench is formed by etching the pad nitride layer, the pad oxide layer, and the semiconductor substrate through an etching process using an isolation mask. The first insulating layer is formed on the entire structure of the semiconductor substrate having the trench. The first insulating layer is formed into undoped polysilicon. The second insulating layer is formed to bury in the trench and planarize the entire surface of the semiconductor substrate. The first and second insulating layers are etched by a CMP(chemical mechanical polishing) method until the pad nitride layer is exposed.
Patent KR-20010059335-A (KR)
Inventor: BAE HAN IL
IPC: G05D1/00
Filed: 1999-12-30
Abstract: PURPOSE: A steering device of an unmanned vehicle for collision test is provided to improve the safety and the reliability of the collision test by using not only linear path but also curve path with the unmanned vehicle. CONSTITUTION: A steering device of unmanned vehicle includes a lead antenna(22), an electronic control device(24), and a steering device(26). The lead antenna(22) detects an electromagnetic field generated at a leading wire. The electronic control device(24) controls the steering device(26) by deciding a target locus and an error. The steering device(26) controls front wheels according to a fixed locus by receiving a signal of the electronic control device(24).
Patent KR-20010066197-A (KR)
Inventor: KIM SANG GON
IPC: E05B1/00
Filed: 1999-12-31
Abstract: PURPOSE: An outer knob of a vehicle door is provided to convert the operation of the handle from the to and fro direction to the up and down direction for reducing the operation force of the handle, thereby improving the whole manipulation when opening or closing the door. CONSTITUTION: An outer knob(10) of a vehicle door includes a handle(12) disposed on a front surface of a housing, a hinge point(13) of the handle, and a rod(15) operating in association with the manipulation of the handle, wherein the hinge point is formed on the handle with a predetermined distance from a horizontal position of the handle for operating the handle in the vertical direction, and the rod is formed with a connection part at a predetermined position on the hinge point, a distance(L5) between the handle and the hinge point being larger than a distance(L6) between the hinge point and the rod.
Patent KR-20000068121-A (KR)
Title: 정보 신호 디코딩 방법 및 장치
IPC: H04N21/44
Filed: 1998-06-12
Abstract: MPEG 디코더 등에서, 영상이 프리즈될지라도 음성을 출력하고 프리즈로부터의 해제 직후에 음성과 영상을 동기시킨다. 
     동화상 데이터의 프리즈 및 그것의 연속적 출력이 메모리(8)내의 제 3 출력 버퍼 영역(8D)을 사용하여 행하여진다.  프리즈중에 입력되는 동화상의 데이터 스트림에서의 I 및 P 화상은 제 1 출력 버퍼 영역(8B) 및 제 2 출력 버퍼 영역(8C)을 이용하여 디코딩된다.  또한, 음성의 데이터 스트림은 동화상과 동기 관계를 유지하면서 디코딩된다.  디코딩된 I 및 P 화상은 프리즈중에라도 제 1 출력 버퍼 영역(8B) 및 제 2 출력 버퍼 영역(8C)에 저장되기 때문에, 영상 데이터는 프리즈로부터의 해제 직후에 음성 데이터와 동기하여 출력될 수 있다.
Patent KR-20000048897-A (KR)
Inventor: WILLIAMS ROGER O
IPC: B24B37/04
Filed: 1997-10-03
Abstract: PURPOSE: An improved method and apparatus is provided for controlling the depth of removal by a chemical mechanical polishing of a selected material on a supporting semiconductor underlayer where it is desired to terminate removal of the selected material, such as silicon oxide, at a specified depth. CONSTITUTION: A selected material such as a surface oxidization layer is polished to initiate removal thereof in the direction of the material-underlayer interface. This system includes three primary components: a chemical mechanical wafer polishing machine, a semiconductor thin film thickness measurement device, and statistical signal process algorithm and its associated computer system provides a chemical mechanical polishing system control by analysis and prediction of the current and future removal rates based on performance of past ratios for the before and after semiconductor thin film thickness measurements.
Patent KR-20000069051-A (KR)
Title: 비트스트림의 디코딩 처리 요구량의 측정치를 추출하는 장치 및 방법
IPC: H04N21/6332
Filed: 1998-09-28
Abstract: 본 명세서에 기술되어 있는 본 발명은 비트스트림을 디코딩하기 위한 처리 요구량의 측정치를 결정하기 위해 비트스트림으로부터 구문 구성 요소를 추출하는 방법을 설명한다. 이 측정치들은 디코더의 성능 요구량에 대한 지식에 기초하여 디코더 자원의 동적 할당을 허용한다. 상기 방법은 관련 구문 구성 요소를 추출하는 파서, 비트스트림 요구량의 측정치를 발생하는 프로세서 및 상기 측정치들이 필요할 때 사용 가능하게 하는 버퍼를 사용한다.
Patent KR-20000057442-A (KR)
Title: System for maintaining datastream continuity in the presence of disrupted source data
Inventor: KRANAWETTER GREG ALAN US
IPC: H04N7/30
Filed: 1997-12-15
Abstract: PURPOSE: A system is provided for maintaining data-stream continuity in the presence of disrupted source data. CONSTITUTION: A video decoder(10) capable of transcoding video data from various input formats to a predetermined output format is disclosed. Input data may be standard definition (NTSC or PAL) data or MPEG compressed data. Standard definition data are rearranged into block format to be compatible with the decoder's(10) single display processor(40). The display processor(40) includes a block-to-line converter(56,58) and selectively processes and conveys either MPEG format data or non-MPEG format data to a display device. A block based memory(20) stores MPEG and non-MPEG pixel block data. The decoder is capable of receiving and displaying burst and non-continuous transmissions
Patent KR-20000070634-A (KR)
IPC: C07K14/75
Filed: 1998-01-30
Abstract: A stabilized solution of fibrinogen containing samples, in particular a stabilized solution of the biological active component (BAC) which is a solution of proteins derived from blood plasma comprising fibrinogen, tranexamic acid and arginine or lysine or mixtures or arginine and lysine, their pharmaceutically acceptable salts, as well as, optionally, substances forming a buffered solution in aqueous medium.
Patent KR-20000075580-A (KR)
IPC: C07J13/00
Filed: 1998-12-23
Abstract: 본 발명은 다양한 질환, 특히 에스트로겐-의존성 질환를 치료하는데 유용한 신규한 항에스트로겐성 화합물을 제공한다. 바람직한 화합물은 1,3,5-에스트라트리엔 핵을 가지며, 화합물이 에스트로겐이 그의 수용체에 결합하는 것을 경쟁적으로 차단하는데 효과적이 되도록 하는 분자부분구조에 의해 C-17 또는 C-11 위치에서 치환된다. 특히 바람직한 화합물은 17-데스옥시-1,3,5-에스트라트리엔이다. 본 발명은 또한 치료학적 방법 및 제약 조성물도 제공한다.
Patent KR-20000076359-A (KR)
Title: 흡수 냉온수기의 고온재생기
IPC: F25B15/06
Filed: 1998-11-11
Abstract: 브롬화리튬의 희석용액을 가열농축하여 냉매인 수증기를 분리하는 흡수냉온수기용 고온재생기이다.  연소가스를 내뿜는 버너(4B)의 분출구측에 내통(2)에 의하여 연소실(11B)을 구획한다.  연소실의 상하로서 외통(1)에 구획된 액실에 용액이 수용된다.  외통의 상부에는 냉매증기유출로(8)가 연소실의 버너와 반대단에는 가스배기로(13, 14)가 각각 형성되어 있다.  연소실의 상하의 액실을 연통하는 복수의 용액관(3)이 연소실을 관통하고 있다.  복수의 용액관은 측면에 핀(16)을 가지는 편평한 관이다.  핀은 상류측에만 설치한다.  이 핀에 의하여 편평관내에 충만한 용액과 연소가스 사이에서의 열교환이 진행되어 용액의 유동이 촉진된다.
Patent KR-20000076389-A (KR)
Title: 무선에 의한 열차 제어방법 및 무선 열차 제어 시스템
Filed: 1997-03-19
Abstract: 무선통신을 이용한 열차 제어에 있어서, 스펙트럼 확산 통신의 동기기술에 착안하여, 동기의 상태를 이용하여 무선통신의 전송로 상황을 파악하거나, 기기 고장의 판정도 용이하게 실현할 수 있는 통신 시스템을 제공한다. 또한, 지상국과 차상국에서 복수의 암호화 키와, 긴급통신시의 긴급 코드를 준비해 두고, 프로토콜 신호를 사용하여 주고받음으로 일치를 도모하며, 통상의 제어신호는, 복수의 암호 방식이 혼재한 신호로 통신을 행하고, 긴급 통신시에는 통일된 신호로 통신할 수 있는 시스템을 제공한다. 또한, 열차 등록 프로토콜시에 주어지는 동적인 ID 코드를 사용하여, 운전 종료시의 열차의 제어대상으로부터 말소시의 처리도 높은 안전도로 행할 수 있는 시스템 제어방식을 제공한다.
Patent KR-20010005884-A (KR)
IPC: H04B7/26
Filed: 1998-02-13
Abstract: 시분할 다중화에 의해 형성된 타임슬롯이 적어도 주파수 방향에서 복수의 블록으로 나누어지고, 또한 복수의 서브캐리어가 각 블록 내에 형성된다.    소정 수의 블록이 1통신채널을 형성하며, 타임슬롯 내에 복수의 통신채널이 형성된다.    이것으로써, 1타임슬롯이 주파수로 분리된 다중 캐리어의 통신에 의해 다중화될 수 있다.    이러한 방식에 의해, 간단한 구조로써 다중경로가 존재하는 환경 하에서도 만족스럽게 통신이 수행될 수 있다.
Patent KR-20010012803-A (KR)
Title: 고용량의 가스 저장 및 분배 장치
Filed: 1998-05-20
Abstract: 본 발명은 물리적 흡수제(14)에 수착(收着)될 수 있고 이러한 수착에 이어 압력 및/또는 열을 매개로 한 탈착(脫着)에 의해 상기 흡수제로부터 탈착될 수 있는 유체를 저장하고 필요시에 분배하는 장치에 관한 것이다.  본 발명의 장치는 상기 물리적 흡수제(14)를 담는 저장 및 분배 용기와, 탈착된 가스 보전 구조체, 예컨대 물리적 흡수제(14)로부터 탈착되고, 후에 그 유체를 배출하는 보전 구조체(112) 쪽으로 유동하는 유체를 보전하는 저장 용기(101) 또는 연장된 길이의 가스 유동 도관을 포함한다.  펌프(118)가 상기 저장 및 분배 용기(101)와 가스 유동 연통되게 작동식으로 결합되어, 흡착된 유체를 유체 보전 구조체(112)로 수송한다.  작동 조립체(120)가 상기 보전 구조체(112) 내에 보유되는 유체의 압력을 모니터하여, 후에 구조체로부터 유체를 배출할 수 있게 상기 보전 구조체(112) 내의 유체를 미리 정해진 압력 범위 및 양으로 유지한다.
Patent KR-20010013478-A (KR)
Inventor: OSBORN THOMAS WARD III
IPC: A61F13/15
Filed: 1998-06-03
Abstract: Absorbent articles such as sanitary napkins, pantiliners, and incontinence pads are disclosed. This development relates to sanitary napkins and other disposable absorbent articles which have an extensible main body portion and which are designed to be adhered directly to the pudendal region of the body of the wearer. This development is directed to extensible disposable absorbent articles which may be directly adhered to the body of the wearer without the use of longitudinal end tabs or side edge tabs. A sanitary napkin of the present invention may contain at least some elastically stretchable components providing the sanitary napkin with an overall elastic stretchability during wear. Additionally, the topsheet, backsheet, and absorbent core may all be elastically stretchable. The absorbent article is provided with a body contacting adhesive to yield an extensible, body adhering absorbent article. An elastically stretchable sanitary napkin of the present invention may be provided with an elastomeric body adhesive.
Patent KR-20010073354-A (KR)
Title: Apparatus for removing interference signal in radio communication system
Inventor: LEE EUN GI
IPC: H04B15/02
Filed: 2000-01-14
Abstract: PURPOSE: A device for eliminating interruption signals in a wireless communication system is provided to efficiently and adaptively eliminate interruption signals of an identical frequency. CONSTITUTION: An attenuation signal generator(20) receives transmission signals to be transmitted through a transmission antenna(26), and controls the transmission signals to be generated as attenuation signals, by responding to control signals for applying amplitude and phase identical with interruption signals changed according to peripheral environments of the transmission antenna(26) and a receiving antenna(28). A subtracter(24) subtracts the attenuation signals from signals received through the receiving antenna(28) to extract desired signals, and outputs the extracted signals as received signals. A control signal generator(22) mixes the received signals and tracer signals, to generate signals of a direct current indicating the degree of interruption signals remaining in the received signals as control signals.