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 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.     

微波介质谐振器温度系数的快速检测系统

谐振频率温度系数是微波介质陶瓷材料的重要性能参数之一,文中提出了一种微波介质谐振器温度系数的新型快速检测方法,并介绍了系统的测试原理、电路结构和软件组成。该系统对微波陶瓷材料温度系数进行测量时,所产生的系统误差、人为误差最小,可实现精确和快速检测。     

介质谐振器反馈型GaAs FET振荡器

本文扼要分析了高Q介质反馈型FET振荡器的原理,认为介质反馈型振荡器类同于高Q介质谐振器与FET栅极耦合的反射型振荡器。实验表明,在-40～+55℃范围内,频率稳定度达2.0ppm/℃,最佳可小于0.2ppm/℃。同时,介质温度系数对振荡电路的过补偿比欠补偿更有利于提高输出功率温度稳定性。     

高Q Ba(Zn_(1/3)Ta_(2/3))O_3介质谐振器材料及其在毫米波系统中的应用

叙述了Ｂａ（Ｚｎ１／３Ｔａ２／３）Ｏ３介质谐振器材料的制备、结构、微波性能及典型应用。Ｂａ（Ｚｎ１／３Ｔａ２／３）Ｏ３介质材料介电常数εｒ为２９．５，频率温度系数τ≈０（－５５～＋８５℃），１０ＧＨｚ下最大无载Ｑ值１４７００，在２８ＧＨｚ测得Ｑ值约为４８００。这种材料具有高Ｑ值，特别适用于Ｘ以上波段作为振荡器电路中频率稳定元件。用这种介质谐振器已研制出８ｍｍ介质稳频微带耿氏振荡器，频率稳定度小于１０×１０－６／℃，最大输出功率达１８０ｍＷ。     

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.     

一种X 波段串联反馈介质振荡器的设计

在毫米波通信系统中,振荡器是最基本的微波频率源。本文介绍了一种串联反馈型介质振荡器的设计方法, 基于负阻理论和谐波平衡法,利用HFSS 和ADS 设计了10.5Ghz 的低相位噪声串联反馈型介质振荡器。HFSS 用来精 确仿真介质谐振器与微带线的耦合;ADS 用来对振荡器非线性仿真,优化相位噪声和输出功率。在设计过程中,采 用低噪声PHEMT 晶体管ATF-34143 作为振荡器的有源器件,高Q 值、高介电常数的介质谐振器作为稳频元件,确 定振荡器的谐振频率。     

基于CST与ADS的介质谐振振荡器的设计

分析了介质谐振振荡器的起振和稳频的原理,研究了一种低相位噪声的介质谐振振荡器的设计方法。以X波段为例,利用CST Microwave Studio 2010软件仿真了微带线与介质谐振器耦合的模型,将仿真得到的结果导入S2P文件中。再利用Agilent ADS 2011软件仿真介质谐振振荡器的完整电路,采用S参数仿真和谐波仿真分析等方法设计介质谐振振荡器,结合理论分析,调整和修改实验电路的参数值,使模型达到最好的优化结果。最后通过测试验证仿真结果。采用NEC公司的2SC5508芯片作为放大器,得出微波振荡器的输出频率为10.6 GHz,输出功率为5.19 dBm和较低的相位噪声,其在偏离中心频率10 kHz处小于-121 dBc/Hz。     

厚度伸缩压电陶瓷振子

对厚度伸缩压电陶瓷振子的振动状态进行了分析,并得到其等效电路.推导了振子的谐振频率、反谐振频率以及等效电路参数与振子尺寸、振子材料的介电、压电、弹性常数间的关系式.最后讨论了振子的一些特性和制作.     

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.     

Systematic evaluation and analysis for 60-GHz dielectric resonatorscoupled to a microstrip line on a GaAs substrate

This paper presents the first systematic evaluation and analysis of 60-GHz-band TE_01δ-mode cylindrical dielectric resonators coupled to a microstrip line on a GaAs substrate. The loss components of the unloaded Q are analyzed using simple numerical techniques. The distance between the resonator center and the microstrip line which gives the maximum coupling coefficient is found to be approximately 3/5 of the resonator radius, whose ratio is almost constant for all practical cases. The temperature characteristics are also demonstrated and the origins of temperature dependences of the unloaded Q and the coupling coefficient are discussed. An equivalent circuit model for the dielectric resonator coupled to the microstrip line is presented, whose element parameters can express the dependences of the resonant frequency, the unloaded Q, and the coupling coefficient on the structural parameters and the temperature     

高稳定Ka波段微带耿氏振荡器

报道了一种使用介质谐振器稳频的高性能和高稳定的Ka波段全微带GaAs Gunn振荡器。在33GHz下,输出功率高达170mW,频率稳定度为9.7ppm/℃。     

Low phase-noise microwave oscillators with interferometric signal processing

Phase-noise spectral density of a 9-GHz oscillator has been reduced to -160 dBc/Hz at 1-kHz offset frequency, which is the lowest phase noise ever measured at microwave frequencies. This performance was achieved by frequency locking a conventional loop oscillator to a high-Q sapphire dielectric resonator operating at the elevated level of dissipated power (/spl sim/0.4 W). Principles of interferometric microwave signal processing were applied to generate the error signal for the frequency control loop. No cryogenics were used. Two almost identical oscillators were constructed to perform classical two-oscillator phase-noise measurements where one oscillator was phase locked to another. The phase locking was implemented by electronically controlling the level of microwave power dissipated in the sapphire dielectric resonator.     

An X-band integrated circuit FET oscillator with dielectric resonator stabilization

Experimental results are presented for the performance of a MIC common drain GaAs FET oscillator and are compared with the performance of the same oscillator stabilized by using a high Q. temperature compensated dielectric resonator made from barium nonatitanate. The unstabilized oscillator gave 85 mW of Rf power at an efficiency of 20%. whilst the compensated oscillator gave 46 mW of power at an efficiency of 12%. with a line width of only 0.3 MHz as measured at 60 dB below the peak. Over the temperature range 0 to 60°C the frequency of the stabilized oscillator changed only 5 MHz, compared t0 the 30 MHz change found in unstabilized oscillators. Mechanical tuning was easily achieved, and careful choice of coupling between the resonator and oscillator eliminated the hysteresis observed in the mode of oscillation of designs previously reported.     

A compact millimeter-wave finline and microstrip hybrid integrated front-end

Unlike usual millimeter-wave(MMW) beam lead mixer, an integrated mixer using packaged diodes with large junction area is designed, and a novel dielectric resonator stabilized microstrip oscillator is given. On these bases, a high performance MMW finline and microstrip hybrid integrated front-end has been developed with minimum double side band noise figure of 4 dB and frequency temperature coefficient of 5～10 PPm/°C. It has been fabricated in small amounts and works well in many MMW systems.     

A Novel Low-Noise Downconverter System Using A Microstrip Coupled Transmission-Mode Dielectric Resonator (Short Paper)

A low-noise downconverter system for microwave downlink applications is presented. Although most downconverters with an internally generated local oscillator have been designed utilizing MESFET's and DGFET's, the circuit described herein uses a silicon bipolar Darlington pair as its active device and a dielectric resonator for feedback. Downconverters of the latter type have been realized with noise figures as low as 4.57 dB and conversion gains of 7 dB over an intermediate frequency range from 0.6 to 1.8 GHz.     

C波段高稳定陶瓷谐振振荡器设计

文章介绍了利用陶瓷谐振器（CR）来提高振荡器频率稳定度的方法,并利用专用微波电路设计软件（AWR）对该方法进行了分析,同时还对压控支路进行了温度补偿设计。根据分析结果制作的C波段高稳定陶瓷振荡器取得令人满意的指标：在全温范围测试结果为温漂≤50×10^-6／℃,带内线性≤1．1,频率稳定度≤＋15MHz,相噪≤-108...     

A double-stage injection-locked oscillator for optically fed phasedarray antennas

In an optically fed phased array antenna system, the microwave carrier signal is transmitted via a modulated lightwave to each active T/R (transmit/receive) module, where it must be converted back to the microwave domain. Currently, efficient optical-to-microwave conversion is extremely difficult, as the detected microwave signal is weak and noisy. A novel circuit, containing a high-gain/low-noise microwave injection-locked oscillator, has been developed to improve the interface between the optical and microwave components. The circuit utilizes two FETs and a dielectric resonator, which serves as a frequency-dependent feedback element. The circuit, designed to operate at about 8 GHz, provides significant amplitude and phase noise suppression. In addition, the circuit realization is compatible with MMIC technology     

C波段高稳定陶瓷谐振振荡器的设计

介绍了利用陶瓷谐振器（CR）来提高振荡器频率稳定度的方法,并利用专用微波电路设计软件（AWR）对该方法进行了分析,同时还对压控支路进行了温度补偿设计。根据分析结果制作的C波段高稳定陶瓷振荡器取得了令人满意的指标：在全温范围测试结果为温漂≤50 ppm/℃,带内线性≤1.1,频率稳定度≤±15 MHz,相噪≤-108 d...     

Ku频段多通道抗振激励源设计

介绍一种Ku频段多通道抗振激励源设计,采用X频段抗振低相噪介质稳频振荡器(DRO),通过结构固连减少各部分电路在振动环境中的相对运动,保证了激励源在振动条件下的稳定性.采用二次谐波镜频抑制混频器一次变频,简化了激励源电路并实现了对本振泄漏的高抑制度和良好的边带抑制.多芯片微带混合集成设计实现了激励源的小型化.研制的样机达到了振动环境下相噪优于-97 dBc/Hz@10kHz,本振抑制大于32 dB、边带抑制大于35 dB的优良性能,验证了设计技术的有效性.