• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.491-492
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• 2006

The MMIC (Microwave Monolithic Integrated Circuit) self oscillating double conversion mixer was designed and fabricated for the V-band transmitter applications. The MMIC self oscillating double conversion mixer which dose not need external local oscillator was designed using GaAs PHEMT technology. The first self oscillating mixer use PHEMT technology. The first self oscillating mixer use PHEMT for $f_{LO}$ signal generation and $f_{IF}$ signal is applied at gate port and $f_{RF1}$ signal is generated at a drain port of first stage. The second gate mixer use PHEMT for $f_{LO}$ signal and $f_{RF1}$ signal is applied at gate port and $f_{RF2}$ signal is output at a drain port of second stage.

• 한국정보통신학회논문지
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• 제7권3호
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• pp.492-498
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• 2003

본 논문은 캐스코드결합에 의한 마이크로파 자기발진믹서를 설계하기 위하여 믹서가 최적 변환이득을 나타내는 바이어스 조건에 대해 분석하였다. 마이크로파 자기발진믹서는 두 개의 GaAs MESFET를 케스코드 결합시켰으며 상위 MESFET는 비교적 높은 Q값을 가지는 유전체공진기에 의해서 발진기로 동작시키고 아래쪽 FET는 저잡음 특성과 최적의 변환이득을 나타내는 믹서로서 동작시켰다. 분석결과 드레인 전압은 $V_{ds}=2.5V$이고 게이트바이어스 전압은 $V_{gs1}=-0.2V와 \;V_{g2}=0V$로 선정하였을 때 설계된 5.15Ghz의 발진기 출력은 5.92dBm, 위상잡음은 -132.0dBc@100KHz, 믹서의 변환손실은 약 -3dB를 나타내어 이론에 의한 자기발진믹서를 설계할 수 있음을 보였다.

• 대한전자공학회논문지
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• 제24권3호
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• pp.413-419
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• 1987

In this paper, self-oscillating mixer is designed by small signal S-parameter and series feedback circuit. The input-output matching circuit is accomplished from double stub and additional matching stub. The self-oscillating mixer is oscillating itself and amplifies without any external local oscillator and an intermediate frequency amplifier, so it has advantages in its economical and system simplification. The experimental results show the maximum conversion gain 1.5d B and the noise figure 6.5d B at RF center frequency 4GHz and IF 1.1GHz` output oscillating power 4d Bm, efficiency 13.4%, stability -10MHz/V and -0.5MHz/\ulcornerC at oscillating frequency 5.1GHz.The rejection band loss characteristics in band pass filter and low pass filter are -40d B and -30d B, respectively.

• 한국정보기술학회논문지
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• 제16권11호
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• pp.61-68
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• 2018

도플러 레이더에 응용할 목적으로 전압제어 발진기와 주파수 혼합기가 합쳐진 10.525GHz 자체발진 혼합기 반도체 IC 칩을 실리콘 CMOS 기술을 이용하여 설계하였다. 자체발진 혼합기에 포함된 p-코어 형태의 VCO는 송신신호에 포함된 잡음을 최소화한다. 이 잡음 최소화는 센싱 가능 거리를 늘여서 움직임 감지센서의 도달거리와 도달감도에 유리한 방향으로 작용한다. 위상잡음에 대한 시뮬레이션 결과 P-코어로 설계된 VCO는 1MHz 오프셋에서 -106.008dBc/Hz, 25MHz 오프셋에서 -140.735dBc/Hz의 잡음특성을 가짐으로써 N-코어 및 NP-코어로 설계된 VCO에 비하여 우수한 잡음 특성을 보였다. 본 연구에 의한 p-코어로 설계된 VCO를 이용하여 자체 발진 혼합기를 구현한다면 도달거리와 도달감도가 우수한 움직임 감지센서를 제작할 수 있을 것이다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 통신소사이어티 추계학술대회논문집
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• pp.86-89
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• 2003

In this paper, Self-Oscillating Mixer is designed by oscillator that was based on a general nonlinear input-output model for the subharmonic injection locked oscillator is analysed. We have designed and fabricated the Self-Oscillating Mixer for 5GHz by proposed subharmonic injection locked oscillator based frequency synthesizer structure that have characteristic of good frequency sensitivity, good phase noise. The design strategy leading to an optimized SILO with regards to its locking range is described and a test SOM circuit is demonstrated a 4dB conversion gain at 280MHz IF frequency from the carrier.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(1)
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• pp.435-438
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• 2002

A design of Ku-band(11.7~12.20Hz) monolithic microwave integrated circuit(MMIC) low noise block(LNB) downconverter using self oscillating mixer (SOM) for direct broadcast satellite(DBS) application is presented The proposed LNB downconverter is composed of low noise amplifier(LNA), image reject filter(IRF), SOM , low pass filter(LPF). The conversion gain is 30dB , VSn is less than 1.7: 1 and overall noise figure is less than 1.2dB.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2000년도 춘계종합학술대회
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• pp.132-134
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• 2000

This paper presents self-oscillating mixer(SOM) with simple structure which includes dc source, a cross type groove, and a three terminal GaAsFET. By using parasitic elements such as cooper wires, If level of the active antenna is increased. In order to include active device into FDTD analysis, equivalent voltage source are used to substitute for the active device and to describe the voltage-current relationships. This approach is applied to analyze SOM theoretically.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 C
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• pp.1958-1960
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• 2003

Here we describe a unique self-oscillating mixer (SOM) design using a modified defected ground structure (DGS) for down-converter. Proposed SOM is consisted of self-oscillator, which can produce negative resistance and select resonance frequency, and input/output matching filter. As the advantage of this SOM can be reused by module that mix signals with transistor that is used to oscillator, it is simply and low-costly designed Also, there is easy advantage to be applied in RFIC/ MMIC technology because it offers excellent high Q value in spite of using micro-strip structure. Designed self-oscillating frequency is 1.04GHz and RF frequency established is 0.8GHz. It was achieved 20dB conversion loss and phase noise of -95dBc/Hz at 100KHz offset frequency over intermediate frequency (IF). The equivalent circuit parameters for DGS are extracted by using a three dimensional EM simulator and simple circuit analysis method.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2000년도 춘계종합학술대회
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• pp.139-142
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• 2000

본 논문에서는 마이크로파 트랜시버용 자기발진믹서를 설계·제작하였다. 설계된 자기 발진기는 10.75GHz의 동작주파수에서 4.33dBm의 출력을 보였으며 위상잡음은 100KHz의 offset주파수에서 -102dBc/Hz의 특성을 보였다. 입사신호 11.7호z∼12.9GHz를 인가시켰을 때 If 주파수 950MHz∼2150MHz 범위에서 변화이득은 6dB로 나타났으며 설계된 SOM은 디지털 트랜시버 시스템의 하향변환기에 적용할 수 있음을 확인하였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 추계종합학술대회 논문집
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• pp.291-294
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• 1999

This paper presents a GaAs MESMET self oscillating mixer for high efficiency L-band frequency conversion with small chip area consumption. Main circuit topology is consist of cascoded two FET with resonating part. The circuit is designed as unstably nonlinear for limited frequency band. FET with drain shorted to source is used for frequency tuning element. Linear conversion gain of -18.83 ㏈ is achieved with 9mA and 4V consumption. Input 1㏈ compression point is more than 11㏈m. The chip area is 1.4$\times$1.4 mm.