• 전기학회논문지
• /
• 제62권12호
• /
• pp.1700-1705
• /
• 2013

A second harmonic millimeter wave oscillator utilizing sub-harmonic injection-synchronization is presented. A 8.7GHz oscillator with MES-FET is designed, and is driven as a harmonic output oscillator at 17.4GHz by means of sub-harmonic injection-synchronization. The oscillator operates as a multiplier as well as a oscillator in this scheme. Adopting this method, a high sable, high frequency millimeter wave source is obtainable even though self-oscillating frequency of an oscillator is relatively low. The range of injection-synchronization is about 26MHz, and is proportional to the input sub-harmonic power. The spectrum analysis of the 2nd harmonic output frequency shows remarkably decreased the phase noise level.

• 한국정보통신학회논문지
• /
• 제12권1호
• /
• pp.17-24
• /
• 2008

서브하모닉파 주입동기에 의한 밀리미터파 대역 고주파원의 고성능화에 대하여 다루었다. MES-FET로 8.7GHz의 발진기를 구성하고 서브하모닉파의 주입동기 방식으로 구동하여 17.4GHz의 고조파를 발생시켰다. 이러한 시스템에서 발진기는 발진과 동시에 체배기의 기능을 수행하여 안정된 고조파 발생시킬 수 있다. 이 기술을 채택하면 자려발진주파수가 비교적 낮은 발진기로도 고안정, 고출력 고주파를 발생시키는 고조파출력 발진기를 실현할 수 있다. 실험의 결과, 주입 동기의 범위 26MHz 내에서 고출력 고조파가 관측되었으며, 서브하모닉파 주입전력에 비례하였다. 스펙트럼 분석기로 고조파 출력의 파형을 관측한 결과, 제2고조파 출력의 위상 안정성이 현저히 향상되었음이 확인되었다.

• 한국통신학회논문지
• /
• 제21권12호
• /
• pp.3215-3226
• /
• 1996

In this paper a K-band harmonic oscillator competitive to ordinary Push-Push type oscillators is introduced. This oscillator is composed of two-X-band dielectric resonance circuits. To favor its harmonic generation, the load effect and the bias effect are studied to allow the maximum harmonic distortion. As results, the dielectric resonated load and the class A bias are used for the 2nd harmonic generation. analytical study for modelling of voltage controlled dielectric resonator is carried out with theoretical background. The performance of the circuit is evaluated by simulation using harmonic balanced method. The novel structure has ont only a voltage tuning circuit but also an output port at fundamental frequency as the function of prescaler for phase lockede loop application on the just single oscillation structure. In experimentation, the output freqneyc of the 2nd harmonic signal is 20.5GHz and the maximum power level of output is +5.5dBm without additional post amplifiers. the harmonic oscillator exhibits -30dBc of high fundamental frequency rejection without added extra filters. The phase noise of -90dBc/Hz at 100kHz off-carrier has been achieved under free running condition, that satisfies phase noise requirement of IESS 308. The proposed oscillator may be utilized as the clean and stable fixed local oscillator in Transmit Block Upconvertor(TBU) or Low oise Block downconvertor(LNB) for K/Ka-band digital communications and satellite broadcastings.

• Journal of electromagnetic engineering and science
• /
• 제5권2호
• /
• pp.92-96
• /
• 2005

This paper presents a novel microwave oscillator incorporating a simple microstrip ring type resonant cell as its terminating resonance component. Reduced chip size, higher dc-ac power efficiency, superior harmonic characteristics can be achieved from the introduction of a compact microstrip ring resonator cell. The oscillator provides a second harmonic suppression of 26.51 dB and the output power of 2.046 dBm at 2.11 GHz.

• ETRI Journal
• /
• 제33권1호
• /
• pp.125-127
• /
• 2011

This letter presents a new type of resonator, namely, the split quarterwave microstrip resonator (SQMR), to improve the poor harmonic suppression and low Q-factors in conventional quarterwave microstrip resonators. An oscillator incorporating the proposed SQMR is designed, fabricated, and tested to demonstrate that, not only the second harmonic suppression, but also the phase noise of the oscillator can be improved. The oscillator with the SQMR shows improved second harmonic suppression of -74.59 dBc and phase noise figure of merit of -169.77 dBc/Hz at 1 MHz offset.

• Journal of electromagnetic engineering and science
• /
• 제6권3호
• /
• pp.160-164
• /
• 2006

This paper describes a compact printed helical resonator and its application to a microwave oscillator circuit implemented in coplanar waveguide(CPW) technology. The high Q-factor and spurious-free characteristic of the resonator contribute to the phase noise reduction and the harmonic suppression of the resulting oscillator circuit, respectively. The designed resonator resonating at the frequency of 5.5 GHz showed a loaded Q of 180 in a chip area of only 40 % of the corresponding miniaturized hairpin resonator without any spurious resonances. The fully planar oscillator incorporated with this resonator showed additional phase noise reduction of 10.5 dB at 1 MHz offset and a second harmonic suppression enhancement of 6 dB when compared to those of a conventional CPW oscillator without the planar helical resonator(PHR) structure.

• 한국전자파학회:학술대회논문집
• /
• 한국전자파학회 2005년도 종합학술발표회 논문집 Vol.15 No.1
• /
• pp.101-106
• /
• 2005

This paper presents a new microwave oscillator incorporating a corrugated coplanar waveguide (CCPW) electromagnetic bandgap (EBG) structure as its terminating resonance component. The use of a compact CCPW EBG structure was effective in reducing the phase noise and improving the harmonic characteristics of the microwave oscillator circuit without additional backside processing and drastic size increment. The fully planar CCPW oscillator oscillating at the frequency of 5.41 GHz showed a phase noise characteristic of -90.7 dBc/Hz at 100kHz offset and a second harmonic suppression of 42.67 dB.

• 한국전자파학회:학술대회논문집
• /
• 한국전자파학회 2003년도 종합학술발표회 논문집 Vol.13 No.1
• /
• pp.304-308
• /
• 2003

A low cost solution employing harmonic oscillation to the frequency synthesizer at 5.8 GHz is proposed. The proposed frequency synthesizer is composed of 2.9GHz PLL chip, 2.9GHz oscillator, and 5.8GHz buffer amplifier. The measured data shows a frequency tuning range of 290MHz, ranging from 5.65 to 5.94GHz, about 0.5dBm of output power, and a phase noise of -107.67 dBc/Hz at the 100kHz offset frequency. All spurious signals including fundamental oscillation power (2.9GHz) are suppressed at least 15dBc than the desired second harmonic signal.

• Bulletin of the Korean Chemical Society
• /
• 제23권2호
• /
• pp.355-356
• /
• 2002

• 한국전자파학회논문지
• /
• 제16권1호
• /
• pp.49-55
• /
• 2005

본 논문에서는 아날로그 위상 고정 루프(PLL: Phase Locked Loop)를 이용한 무선 LAN(Wireless Local Area Network)용 위상 고정 고조파 발진기(PLHO: Phase Locked Harmonic Oscillator)를 설계 및 제작하였다. 이 고조파 발진기는 Ring 공진기, 주파수 동조를 위한 바랙터 다이오드 그리고 위상 고정 루프 회로로 구성된다. 발진기의 8.5 GHz의 기본 주파수는 위상 고정 루프를 위한 귀환 신호로 이용되고 17.0 GHz의 2차 고조파는 출력으로 이용되므로 위상 고정 시스템에서 위상 비교를 위한 주파수 분배기를 한 단계 줄일 수 있다. 위상 비교기로는 샘플링 위상 검출기(SPD: Sampling Phase Detector)를 사용하여 위상고정 루프 회로를 간단히 하였다. 위상고정 고조파 발진기의 발진 출력은 17.0 GHz에서 2.17 dBm, 기본 주파수와 3차 고조파 억압 특성은 각각 -31.5 dBc, -29.0 dBc이다. 위상잡음은 각각 -87.6 dBc/Hz at 1 kHz와 -95.4 dBc/Hz at 10 kHz이다.