• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.8
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• pp.1392-1398
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• 2000

In this paper, Sub Harmonic Ring Mixer using Anti-Parallel Diode Pair is studied. Conventional mixers mix LO signal with RF signal and, obtain IF signal from the difference between LO and RF. Sub harmonic ring mixers using APDP mix RF signal with the second harmonic of LO signal, LO frequency needed for conventional receiver is reduced by 1/2.The produced mixer showed 12 dB conversion loss, and 1 dB compression point of IF signal, in respect to RF signal, was found at the 0 dBm RF signal. Isolation LO/IF and LO/RF is 24.6 dB and 22.5 dB respectively. Isolation RF/LO and LO/RF is 32.6 dB and 22.5 dB respectively.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.1
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• pp.26-32
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• 1994

In this paper, using the newly developed GaAs Schottky beam-lead diode made by Marconi company, we have developed and evaluated the waveguide type single-ended mixer at Q-band. The various components of the mixer were separately designed and optimized using the Super-Compact software. These studies included the design of the step waveguide impedance transformer and the RF-choke filter, and the optimization of a high and low impedance for the RF-choke filter. Moreover, this RF-choke filter pattern included a section to reject the second harmonic frequency of the RF signal. Finally, this Q-band mixer with 1.4GHz/400MHz IF frequency exhibits an average conversion loss of 5.3 dB over 33-50GHz bandwidth.

• Journal of the Korean Institute of Telematics and Electronics T
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• v.35T no.1
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• pp.22-28
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• 1998

A new type of FET source mixer with a single bias voltage has been presented. It is designed to operate at Vds=0 [V] with only one positive supply voltage, which makes mixer circuits simple. The proposed mixer has shown improved stability and less sensitivity to both bias and LO power compared with conventional active mixers. It also shows lower conversion loss than that of diode mixers. The minimum conversion loss measured at RF frequency of 5.6㎓ is 0.6㏈ for a LO frequency of 5.8㎓.

• Journal of the Korean Institute of Telematics and Electronics
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• v.23 no.6
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• pp.868-873
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• 1986

The Schottky barrier diode has been used as an element of the mixer inspite of its conversion loss. In this paper the use of a GaAs MESFET is shown as a device of mixer, and the conversion gain is obtained. Also, input matching circuits aredesigned by s-parameter and fabricated on a dielectric teflon epoxy fiber glass substrate. According to the results, the conversion gain is 9 dB at the signal frequency of 4 GHz and the intermediate frequency of 1.217GHz.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2006.07a
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• pp.718-718
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• 2006

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2000.11a
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• pp.193-196
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• 2000

본 논문에서는 FG-CPW(Finite-Ground Coplanar Wave-Guide) 구조의 단일 평형 다이오드 믹서에 대해서 논의된다. 주파수 영역은 무선 LAN 대역으로 선택하였다. RF 신호는 5.725-5.875 GHz, LO 신호는 5.58GHz, 그리고 IF 신호는 140 MHz가 사용된다. 제시된 FG-CPW 구조의 LPF(low pass filter)는 회의크기를 줄일 수 있으며, 불필요한 하모닉 억제 특성이 우수하다. 5.635 GHz에서 5 dBm의 Power를 갖는 LO신호가 입력될 때 6.2 dB 의 혼합기의 변환손실을 얻는다. 또한 LO-RF isolation과 LO-IF isolation은 각각 30 dB $\Omega$dB 의 특성을 보인다. 이 혼합기는 CPW 구조가 일반적으로 알려진 밀리미터 대역에서의 장점뿐만 아니라 C-Band의 무선 LAN 분야에도 충분히 응용될 수 있으리라 기대된다.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.2
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• pp.257-262
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• 2012

The Ministry of Information-Communication assigned 18~19GHz frequency band for communication of cabins and platform to link between subway/train and it's station. In this paper, we propose wireless transmission devices which are 2 stage hybrid low noise amplifier of 18GHz band and mixer for 18GHz as well to apply for RF receiver. We designed LNA to be noise matched its 1st stage and gain matched for 2nd stage and mixer using $180^{\circ}$ hybrid coupler to suppress the spurious signal. The transistors of 18 GHz LNA and mixer are NE3210S01 of NEC and KMB-N51-1, respectively. As the result of simulation, we get 19.92dB gain and 2.06dB noise figure with LNA and 8.61dB conversion loss with mixer.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.2
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• pp.227-231
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• 2004

A MMIC (Monolithic Microwave Integrated Circuit) mixer chip using the schottky diode of InGaAs/CaAs p-HEMT process has been developed for receiver down converter of Ka-band. A different approach of MMIC mixer structure is applied for reducing the chip size by the exchange of ports between IF and LO. This MMIC covers with RF (30.6∼31.0㎓)and IF (20.8∼21.2㎓). According to the on-wafer measurement, the MMIC mixer with miniature size of 3.0mm1.5mm demonstrates conversion loss below 7.8㏈, LO-to-RF isolation above 27㏈, LO-to-IF isolation above 19㏈ and RF-to-IF isolation above 39㏈, respectively.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2000.11a
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• pp.154-157
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• 2000

One of the problems using DCR(Direct Conversion Receiver) type architecture are DC offset, Poor channel selectivity. APDP(Anti Parallel Diode Pair) can be mood candidate for the DCR frequency mixer due to its inherent 2nd harmonic suppression. APDP shows good IP2 and DC suppression. This paper describes single APDP LO power characteristics, IP2, and receiver structure utilizing APDP frequency mixer.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.7
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• pp.293-299
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• 2003

In this paper, we have proposed a high conversion and isolation characteristic V-band quadruple sub-harmonic mixer monolithic circuit which is designed and fabricated for the millimeter wave down converter applications. While most of the sub-harmonic mixers use a half of fundamental frequency, we adopt a quarter of the fundamental frequency. The proposed circuit is based on a sub-harmonic mixer with APDP(anti-parallel diode pair) and the 0.1 ${\mu}{\textrm}{m}$ PHEMT's (pseudomorphic high electron mobility transistors). Lumped elements at IF port provide better selectivity of IF frequency and increase isolation. Maximum conversion gain of 0.8 ㏈ at a LO frequency of 14.5㎓ and at a RF frequency of 60.4 ㎓ is measured. Both LO-to-RF and LO-to-IF isolations are higher than 50 ㏈. The conversion gain and isolation characteristic are the best performances among the reported quadruple sub-harmonic mixer operating in the V-band millimeter wave frequency thus far.