• 전자공학회논문지A
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• 제33A권6호
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• pp.81-89
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• 1996

Quantum RF impedance of SIS (superconductor insulator superconductor) junction has been analyzed by using through on tucker's quantum mixer theory in the frequency range form 80 GHz to 120 GHz. The embedding impedance of waveguide-type mixer mount and its equivalent circuit have been evaluated. From these evaluated results, the impedance matching efficiency between mixer mount embedding impedance and mixer port impedance of upper-side band and IF which were determined by augmented admittance matrix with given backshort position has been discussed in detail. It is found that the mixer with fixed backshort mount ahs a impedance matching efficiency about 80% at each port of mixer within 85GHz to 115GHz, which implys a conversion los of mixer would be good enough to be operated such a wide band frequency range. Therefore, the theoretical evaluated results show that our method can be used ot design the mixer mount without any mechanical tuning elements such a backshort or an E-plane tunners for wide band operation.

• Journal of electromagnetic engineering and science
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• 제7권4호
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• pp.154-160
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• 2007

A reconfigurable multi-band mixer for the SDR system is proposed. The proposed reconfigurable mixer is operated between $850\;MHz{\sim}2\;GHz$, which includes all commercial mobile communication service. Because the varactor diodes are used to select a specific frequency and to adjust the impedance characteristic of the selected frequency band, the proposed reconfigurable mixer can be achieved to similar performance across all of the tuning range. In addition, the designed reconfigurable mixer is applicable for the SDR system since it has a single signal path for the multi-band signals and wide band tuning range.

• 한국전자통신학회논문지
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• 제13권4호
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• pp.685-694
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• 2018

본 논문에서는 Ku대역 추적레이더의 핵심부품인 고주파 헤드 내 주파수 믹서(혼합기)의 설계 및 제작 결과에 대해서 다룬다. 단일종단(Single-Ended) 및 단일평형(Single-Balanced) 믹서의 단점을 보완하기 위해서, Fine-Line 구조의 평형(Balanced) 믹서를 설계하여 낮은 변환손실 특성을 가지도록 하였으며, Ku대역 RF신호를 입력받아 L밴드 IF신호를 생성하도록 하였다. 제작된 믹서에 대해서 Ku밴드 5개 샘플주파수를 대상으로 실험한 결과, 최대 잡음지수(Noise Figure Max) 6.823dB, 이득(Gain) 4.159dB ~ 4.676dB, 통과대역(Band Pass) 61MHz의 값을 확인하였다.

• 전자공학회논문지A
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• 제33A권6호
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• pp.90-98
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• 1996

We have evaluated the theoretical conversion loss and noise temperature of mixer using the quantum mixer theory and the method to determine the embedding impedance of waveguide-type mixer mount. At fixed backshort position of the mixer, the calculated SSB mixer conversion loss and mixer noise temperature are 5 dB and 10K within frequency range form 85 GHz to 115 GHz, respectively. The SIS mixer has been developed by using through on the calculated rsutls to observe cosmic radio waves. SIS junction of mixer is Nb/Al-AlOx/Nb and it consists of four series array. Area of each of junction is about 2.5${\mu}m^{2}$. The average receiver noise temperature of manufactured receiver with this mixer is about 30 K(DSB). The receiver noise temperature is much lower than that of receiver with a mixer using mechanical tuning backshort.

• Journal of information and communication convergence engineering
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• 제14권1호
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• pp.35-39
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• 2016

In this paper, we develop a 94-GHz single balanced mixer with low conversion loss using planar Schottky diodes on a GaAs substrate. The GaAs Schottky diode has a nanoscale anode with a T-shaped disk that can yield high cutoff frequency characteristics. The fabricated Schottky diode with an anode diameter of 500 nm has a series resistance of 21 Ω, an ideality factor of 1.32, a junction capacitance of 8.03 fF, and a cutoff frequency of 944 GHz. Based on this technology, a 94-GHz single balanced mixer was constructed. The fabricated mixer shows an average conversion loss of -7.58 dB at an RF frequency of 92.5 GHz to 95 GHz and an IF frequency of 500 MHz with an LO power of 7 dBm. The RF-to-LO isolation characteristics were greater than -32 dB. These values are considered to be attributed to superior Schottky diode characteristics.

• 한국전자통신학회논문지
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• 제15권5호
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• pp.827-834
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• 2020

본 연구는 주파수 체배기 이론을 이용하여 초고주파 항공용 레이다를 위한 3차 고조파 믹서 설계에 대한 연구이다. 기본 믹서 설계 방법과는 달리 주파수 체배기 이론을 이용하여 국부 주파수(LO)의 3차 고조파 성분이 최대가 되는 게이트 바이어스 전압을 선택하여 중간주파수(IF)에서 3차 고조파 혼합(mixing) 성분이 최대가 되도록 하였다. 제안한 고조파 믹서는 플라스틱 패키지의 상용 GaAs MESFET 소자를 이용하여 설계 및 제작하여 기존 초고주파 믹서의 높은 변환손실, 회로 복잡성, 높은 가격 및 제작 복잡도를 개선할 수 있었다. 제안한 설계 방법을 이용한 3차 고조파 믹서는 33 GHz ~ 36 GHz 대역에서 8 ~10 dB 변환손실 특성 및 0 dBm 선형성 (P1dB) 특성을 나타내었다.

• International journal of advanced smart convergence
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• 제10권1호
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• pp.12-23
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• 2021

This paper proposes a low power radio frequency receiver front-end where, in a single stage, single-balanced mixer and voltage-controlled oscillator are stacked on top of low noise amplifier and re-use the dc current to reduce the power consumption. In the proposed topology, the voltage-controlled oscillator itself plays the dual role of oscillator and mixer by exploiting a series inductor-capacitor network. Using a 65 nm complementary metal oxide semiconductor technology, the proposed radio frequency front-end is designed and simulated. Oscillating at around 2.4 GHz frequency band, the voltage-controlled oscillator of the proposed radio frequency front-end achieves the phase noise of -72 dBc/Hz, -93 dBc/Hz, and -113 dBc/Hz at 10KHz, 100KHz, and 1 MHz offset frequency, respectively. The simulated voltage conversion gain is about 25 dB. The double-side band noise figure is -14.2 dB, -8.8 dB, and -7.3 dB at 100 KHz, 1 MHz and 10 MHz offset. The radio frequency front-end consumes only 96 ㎼ dc power from a 1-V supply.

• 전기전자학회논문지
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• 제16권2호
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• pp.127-130
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• 2012

In this paper, we reported on a single balanced monolithic diode mixer using Marchand balun for millimeter-wave applications. The single balanced monolithic mixer was fabricated using drain-source-connected pseudomorphic high electron mobility transistor (PHEMT) diodes considering the PHEMT MMIC full process. The average conversion loss is 16 dB in the RF frequency range of 81~86 GHz at LO frequency of 75 GHz with LO power of 10 dBm. The RF-to-LO isolation characteristics are greater than -30 dB and the total chip size is $1.0mm{\times}1.35mm$.

• Journal of electromagnetic engineering and science
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• 제4권4호
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• pp.143-149
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• 2004

This paper describes characteristics of the single-balanced low IF resistive FET mixer for the digital beam forming(DBF) receiver. This DBF receiver based on the direct conversion method is designed with Low IF I and Q channel. A radio frequency(RF), a local oscillator(LO) and an intermediate frequency(IF) considered in this research are 1950 MHz, 1940 MHz and 10 MHz, respectively. Super low noise HJ FET of NE3210S01 is considered in design. The measured results of the proposed mixer are observed IF output power of -22.8 dBm without spurious signal at 10 MHz, conversion loss of -12.8 dB, isolation characteristics of -20 dB below, 1 dB gain compression point(PldB) of -3.9 dBm, input third order intercept point(IIP3) of 20 dBm, output third order intercept point(OIP3) of 4 dBm and dynamic range of 30 dBm. The proposed mixer has 1.0 dB higher IIP3 than previously published single-balanced resistive and GaAs FET mixers, and has 3.0 dB higher IIP3 and 4.3 dB higher PldB than CMOS mixers. This mixer was fabricated on 0.7874 mm thick microstrip $substrate(\varepsilon_r=2.5)$ and the total size is $123.1\;mm\times107.6\;mm$.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 추계종합학술대회 논문집(1)
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• pp.361-364
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• 2000

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