5公分中功率高效率高稳定度FET振荡器

我们研制了一种普通封装的GaAs FET 和高Q介质谐振器的共漏振荡器。这种共漏振荡器采用FET沟道反向的办法,利用自身的栅源电容构成反馈电路,省去了复杂的外反馈网络;还采用了高Q介质谐振器作成反射型的稳频电路,解决了频率稳定度的问题。这种振荡器结构简单、调试方便,在4～6GHz范围内输出功率大于300mw,效率超过30％,机械调谱带宽大于100MHz;在-40～+70℃温度范围内,频漂小于±O.6MHz,频温系数为2×lO~6/l℃。     

X波段介质稳频电调FET振荡器

本文介绍了X波段介质稳频电调FET振荡器(FET DR VCO)的研制。采用反馈型电路结构,获得振荡频率为7774MHz,输出功率Po>10dBm,线性电调带宽>42MHz(功率变化△P<1dB),电调灵敏度为3.0MHz/V,在-20℃～+60℃范围内,频率温度稳定度<±5.7ppm/℃。     

C波段介质谐振器稳频FET振荡器

本文运用电磁场理论对圆柱形介质谐振器进行了分析和计算,并设计制作了C波段反馈型介质谐振器稳频FET振荡器,其工作频率f_0=7.4GHz,输出功率P≥30mW,频率稳定度为±2×10~(-5)(-10～+50℃),频率温度系数为0.67ppm/℃。     

环路反馈式场效应管介质稳频振荡器

本文介绍了一种环路反馈式场效应管介质稳频振荡器.该振荡器主要是由一个FET放大器及一个独立的介质谐振器反馈电路结构组成.通过分别仔细地调试此两部分的指标,可以获得较好性能的振荡器.所研制的振荡器的基本性能为:振荡频率为2.7GHz;从室温到50℃范围内频率稳定度可达0.3ppm/℃;输出功率为5～20mW.     

X波段砷化镓场效应管介质振荡器

本文介绍了反馈型介质振荡器,给出了介质谐振器尺寸的计算方法.该振荡器在8GHz下,温度范围-40～+70℃,频率稳定度为0.6ppm/℃,输出功率16～30mW,在+55℃下连续工作8 小时,频率漂移小于50kHz,推频系数小于10kHz/V,在偏离载频100kHz的FM噪声为-110dBc/Hz.该振荡器在无人值守中继系统中作上下变频器的本振源,使用良好.这类振荡器在10.7GHz下,温度范围-40～+55℃,频率稳定度0.6ppm/℃,输出功率大于5mW.     

双介质谐振腔FET振荡器

介质谐振腔FET(场效应晶体管)振荡器有吸收式、并联反馈式和串联反馈式(反射式)等数种.并联反馈式是利用谐振腔把栅极和漏极耦合起来而形成的振荡器,此类振荡器的性能良好.目前并联反馈式振荡器还没有一个合适的数学模型,设计只能靠经验,并且不便采用普通封装的低噪声放大用的FET.吸收式振荡器比较简单,但当谐振腔放在输出端时,高Q值的谐     

采用介质谐振器的C波段高稳定、低噪声GaAs FET集成振荡器

用BaO-TiO_2陶瓷介质谐振器稳频的GaAs FET集成振荡器提供一种高稳定低噪声小型微波功率源。新研制的陶瓷材料具有互相补偿的膨胀系数和介电常数温度系数,从而得出较小的谐振频率温度系数。振荡器在6千兆赫上得到输出功率100毫瓦,效率为17％,频率温度系数低达2.3ppm/℃。由于稳频使调频噪声电平减小30分贝以上。精确地测量了振荡器和谐振器的动态特性,以确定等效电路形式。介绍了基于这些等效电路形式的大信号设计理论,以便在振荡器和谐振腔之间实现最佳耦合条件。本稳频振荡器的性能可满足微波通讯系统的要求。     

高稳定度中功率C波段耿氏DRO

文章介绍了 C 波段介质谐振器稳频耿氏振荡器实用电路结构,简明分析了耿氏 DRO 稳频和工作原理以及用高 Q 介质谐振器稳频和双金属补偿所得的实验结果:在5.3GHz 附近,振荡器输出功率为280mW,在-40～+60℃范围内,振荡器频率温度系数为0.56PPm/℃,功率温度系数小于0.01dB/℃。     

具有数字式温度补偿的16千兆赫介质谐振腔振荡器

本文讨论了一种用于改善介质谐振腔振荡器(DRO)温度稳定性的数字补偿技术。其结果表明,对一个16.1千兆赫的DRO,在16到52℃的范围内,其频率温度特性从309ppm降低为3.8ppm,几乎减小了两个数量级,相当于平均值只有0.1ppm/℃。(注:ppm即百万分之一)     

反馈型介质腔稳GaAs FET振荡器

本文给出反馈型介质腔稳GaAs FET振荡器较严格的分析模型。导出振荡条件下FET的S参数与反馈电路参数间的关系式、振荡频率以及频率温度稳定度等的关系式。依此研制成两种X波段DRO,均获得良好的频率—温度特性。     

4千兆赫介质谐振器振荡器

本文叙述了介质谐振器作为加载带阻滤波器稳频的基本原理,介绍了4GHz介质谐振器振荡器.该振荡器在-40℃到+55℃范围内,频率稳定度在2ppm/℃左右,在+55℃下连续工作8小时,频率漂移一般在50kHz以内,振荡器的输出功率在10mW左右.该振荡器曾在国际卫星通迅公司5号星电视传输试验中作接收系统的本振源,使用良好.     

A Highly Stabilized Low-Noise GaAs FET Integrated Oscillator with a Dielectric Resonator in the C Band

A GaAs FET integrated oscillator stabilized with a BaO--TiO/sub 2/ system ceramic dielectric resonator provides a high-frequency-stabilized low-noise compact microwave power source. The newly developed ceramic has an expansion coefficient and dielectric constant temperature coefficient that offset each other and result in a small resonant frequency temperature coefficient. A stabilized oscillator output of 100 mW with a 17-percent efficiency and a frequency temperature coefficient as low as 2.3 ppm//spl deg/C are obtained at 6 GHz. FM noise level is reduced more the 30 dB by the stabilization. The dynamic properties of the oscillator and resonator are precisely measured to determine equivalent circuit representations. A large-signal design theory based on these equivalent circuit representations is presented to realize the optimal coupling condition between the oscillator and stabilizing resonator. The stabilized oscillator performance is sufficient for application to microwave communications systems.     

Temperature Stabilization of GaAs MESFET Oscillators Using Dielectric Resonators

A simple model of the temperature stabilization of dielectric resonator FET oscillators (DRO's) is presented. Deduced from the oscillation condition, the model furnishes relations for oscillation power and frequency stability with temperature. A stack resonator with an appropriate linear resonance frequency/temperature characteristic has been developed and used to stabilize a DRO: frequency stability of +- 120 kHz over - 20°C to 80°C (/sup delta=/+- 0.1 ppm/K) at 11.5 GHz has been achieved.     

UHF微带裂环介质谐振器FET振荡器分析

本文提出了微带裂环介质谐振器FET振荡器电路,分析了FET电路和微带裂环谐振器的特性,最后给出设计这种振荡器的频率温度稳定性考虑与优化方法.     

A Highly Stabilized GaAs FET Oscillator Using a Dielectric Resonator Feedback Circuit in 9-14 GHz

A new type of highly stabilized GaAs FET oscillator using a dielectric resonator and a stabilization resistor in the feedback circuit has been developed. The oscillator fabricated with a microwave integrated circuit has a high external quality factor Q/sub ex/ for more than1000 with no hysteresis phenomena. The microwave characteristics of the GaAs FET oscillator has revealed 1) high efficiency of 20 percent with 70-mW output power at 11.85 GHz, 2) a wide tuning range more than1000 MHz, 3) a wide oscillation frequency from 9 to 14 GHz with same MIC pattern by using five dielectric resonators of different sizes, 4) a high-frequency stability as low as /spl plusmn/ 150kHz in the tempature range from -20 to + 60/spl deg/ C, and 5) low FM noise of 0.07 Hz/ /spl radic/Hz at off-carrier frequency of 100kHz.     

A 22-GHz-band low-noise down-converter for satellite broadcastreceivers

A simple low-cost and high-performance 22 GHz band down-converter developed for a direct-to-home satellite broadcasting system is discussed. The down-converter consists of a low-noise high electron mobility transistor (HEMT) preamplifier, an image recovery mixer with a particular structure using dielectric resonator filters, a 21.4 GHz GaAs FET oscillator stabilized by a dielectric resonator, and an IF amplifier. These components are fully integrating using microwave integrated circuit technology into a small size. A total noise figure of less than 2.8 dB is obtained over the 22.5-23.0 GHz frequency range. The local oscillator achieves a frequency variation of less than 600 kHz_p-p over a temperature range of -20° to +60°C     

A Highly Stabilized MIC Gunn Oscillator Using a Dielectric Resonator

An X-band frequency-stabilized MIC Gunn oscillator of a very simple structure using a dielectric resonator is developed. It is studied how the oscillating characteristics can be controlled by circuit parameters, with special attention to the factors affecting the frequency stability with temperature. By optimizing these factors and by selecting the proper temperature coefficient of a newly developed dielectric resonator, the high frequency stability of less than /spl plusmn/100 MHz over the temperature range from -20 to 60/spl deg/C (2x10 /sup -7/ / /spl deg/C) was obtained.     

用于抛掷敏感器的Ka—波段微带集成本振—混频组件

介绍一种用于抛掷敏感器的结构紧凑的Ka－波段微带集成本振－混频组件,给出了该组件的微带电路结构,叙述了其中第一部件的功能。对该组件仔细做了环境和可靠性实验,其中包括震动,冲击和温度。在2GHz射频带宽内,该组件的双边带噪声系数是3.4-4.2dB,在其工作频带内本振动射频的隔离度大于27dB。由于使用了介质谐振器,本振的频率稳定度小于60ppm/℃。