K-band f.e.t. amplifiers

Single-stage f.e.t. amplifiers operating in K-band have been constructed using the Varian VSX 9305 0.5 ?m-gate GaAs f.e.t. An amplifier gain of 9±1 dB was obtained over the frequency band 18.5?20.5 GHz and gain of 8±1 dB was observed from 23.0 to 26.0 GHz. An amplifier noise figure of 5.6 dB was measured at 24 GHz.     

Cryogenic 2?4 GHz f.e.t. amplifier

A cryogenic single-stage broadband f.e.t. amplifier with an average noise temperature of 34 K (0.5 dB) over a bandwidth of 2 GHz has been developed. The average gain is 12 dB. The best spot noise temperature is 17 K (0.25 dB) at 3.2 GHz, which is competitive with cryogenic parametric amplifiers.     

High-performance in W-band monolithic pseudomorphic InGaAsHEMT LNA's and design/analysis methodology

High-performance W-band monolithic one- and two-stage low noise amplifiers (LNAs) based on pseudomorphic InGaAs-GaAs HEMT devices have been developed. The one-stage amplifier has a measured noise figure of 5.1 dB with an associated gain of 7 dB from 92 to 95 GHz, and the two-stage amplifier has a measured small signal gain of 13.3 dB at 94 GHz and 17 dB at 89 GHz with a noise figure of 5.5 dB from 91 to 95 GHz. An eight-stage LNA built by cascading four of these monolithic two-stage LNA chips demonstrates 49 dB gain and 6.5 dB noise figure at 94 GHz. A rigorous analysis procedure was incorporated in the design, including accurate active device modeling and full-wave EM analysis of passive structures. The first pass success of these LNA chip designs indicates the importance of a rigorous design/analysis methodology in millimeter-wave monolithic IC development     

A W-band image-rejection downconverter

The design, fabrication, and evaluation of a W-band image-rejection downconverter based on pseudomorphic InGaAs-GaAs HEMT technology are presented. The image-rejection downconverter consists of a monolithic three-stage low-noise amplifier, a monolithic image-rejection mixer, and a hybrid IF 90° coupler with an IF amplifier. The three-stage amplifier has a measured noise figure of 3.5 dB, with an associated small signal gain of 21 dB at 94 GHz while the image-rejection mixer has a measured conversion loss of 11 dB with +10 dBm LO drive at 94.15 GHz. Measured results of the complete image-rejection downconverter including the hybrid IF 90° coupler and a 10 dB gain amplifier show a conversion gain of more than 18 dB and a noise figure of 4.6 dB at 94.45 GHz     

数字硅MOSFET微波特性的研究

利用国内先进的 0 .6μm数字 Si-MOS工艺 ,设计了射频 MOSFET,并研究了其 DC和微波特性 :I-V曲线、S参数、噪声参数和输出功率。研究发现 ,数字电路用 Si MOSFET的频率响应较高 :频率为 1 GHz时功率增益可达 1 0 d B,2 GHz时为 8d B,4GHz时为 5 d B。 1 .8GHz时 ,1分贝压缩输出功率 1 2 .8d Bm,饱和输出功率可达 1 8d Bm,且最小噪声系数为 3 .5 d B。用提取的参数设计并研制了微波 Si MOSFET低噪声放大器 ,以验证MOS器件的微波性能。此放大器由两级级联而成 ,单电源供电 ,输入输出电容隔直。在频率 1 .7～ 2 .2 GHz的范围内 ,测得放大器增益 1 5± 0 .5 d B,噪声系数 N F<3 .8d B,1分贝压缩输出功率 1 2 d Bm;在频率 1 .5～ 2 .5 GHz的范围内 ,放大器增益大于 1 3 d B。     

7.9?8.4 GHz GaAs m.e.s.f.e.t. amplifier

A 4-stage balanced GaAs m.e.s.f.e.t. amplifier has been developed for the 7.9?8.4 GHz satellite-communication frequency band. Linear gain of 26±0.5dB and 150 mW power at 1 dB compression were obtained across the design band. The small-signal gain, phase linearity, group delay and noise figure are described as a function of frequency. Large-signal gain saturation, 3rd-order intermodulation distortion, gain and phase against temperature and a.m.-to-p.m. conversion data are also presented.     

High-performance Ka-band and V-band HEMTlow-noise amplifiers

Quarter-micron-gate-length high-electron-mobility transistors (HEMTs) have exhibited state-of-the-art low-noise performance at millimeter-wave frequencies, with minimum noise figures of 1.2 dB and 32 GHz and 1.8 dB at 60 GHz. At Ka-band, two-stage and three-stage HEMT low-noise amplifiers have demonstrated noise figures of 1.7 and 1.9 dB, respectively, with associated gains of 17.0 and 24.0 dB at 32 GHz. At V-band, two stage and three-stage HEMT amplifiers yielded noise figures of 3.2 and 3.6 dB, respectively, with associated gains of 12.7 and 20.0 dB and 60 GHz. The 1-dB-gain compression point of all the amplifiers is greater than +6 dBm. The results clearly show the potential of short-gate-length HEMTs for high-performance millimeter-wave receiver application     

（英）D波段InP基高增益、低噪声放大芯片的设计与实现

利用90-nm InAlAs/InGaAs/InP HEMT工艺设计实现了两款D波段（110~170 GHz）单片微波集成电路放大器。两款放大器均采用共源结构,布线选取微带线。基于器件A设计的三级放大器A在片测试结果表明：最大小信号增益为11.2 dB@140 GHz,3 dB带宽为16 GHz,芯片面积2.6×1.2 mm2。基于器件B设计的两级放大器B在片测试结果表明：最大小信号增益为15.8 dB@139 GHz,3dB带宽12 GHz,在130~150 GHz频带范围内增益大于10 dB,芯片面积1.7×0.8 mm2,带内最小噪声为4.4 dB、相关增益15 dB@141 GHz,平均噪声系数约为5.2 dB。放大器B具有高的单级增益、相对高的增益面积比以及较好的噪声系数。该放大器芯片的设计实现对于构建D波段接收前端具有借鉴意义。     

Tunable X band GaAs f.e.t. amplifier

The design of a frequency-tunable X band amplifier using GaAs Schottky field-effect transistors is described. By using a broadband input matching circuit and a frequency-tunable output matching circuit, the gain of 7±0.5 dB obtained from a single-stage amplifier may be varied from 8 to 10 GHz, with corresponding terminal v.s.w.r.s, over any 600 MHz band width, better than 2:1. A single-stage amplifier gives a noise figure of 4.7 dB with a gain of 5.8 dB, and a 2-stage amplifier a 6.0 dB noise figure with 12.5 dB power gain.     

Performance of sulphur-ion-implanted GaAs f.e.t.s

GaAs f.e.t.s have been produced by sulphur-ion implantation that give optimum noise figures as low as 4.6 dB at 10 GHz and maximum available gains of greater than 10 dB at 10 GHz. A considerable degree of uniformity among the devices is observed.     

220GHz低噪声放大器研究

基于IHP锗硅BiCMOS工艺,研究和实现了两种220 GHz低噪声放大器电路,并将其应用于220 GHz太赫兹无线高速通信收发机电路。一种是220 GHz四级单端共基极低噪声放大电路,每级电路采用了共基极（Common Base, CB）电路结构,利用传输线和金属-绝缘体-金属(Metal-Insulator-Metal, MIM)电容等无源电路元器件构成输入、输出和级间匹配网络。该低噪放电源的电压为1.8 V,功耗为25 mW,在220 GHz频点处实现了16 dB的增益,3 dB带宽达到了27 GHz。另一种是220 GHz四级共射共基差分低噪声放大电路,每级都采用共射共基的电路结构,放大器利用微带传输线和MIM电容构成每级的负载、Marchand-Balun、输入、输出和级间匹配网络等。该低噪放电源的电压为3 V,功耗为234 mW,在224 GHz频点实现了22 dB的增益,3 dB带宽超过6 GHz。这两个低噪声放大器可应用于220 GHz太赫兹无线高速通信收发机电路。     

Substrate dependence of InP m.e.s.f.e.t. performance

There is evidence to suggest that Fe outdiffuses, during the growth, into the epitaxial films prepared by vapour-phase epitaxy at 650°C. Field-effect transistors on Fe-doped material show substantial looping that was absent on Cr-doped material and exhibit about 2 dB worse noise figure at about 7 GHz. Experiments with low 1015 S-doped InP grown on Sn-, Cr- and Fe-doped substates indicate that such outdiffusion is typically about 5 ?m. Saturation velocity levels in the m.e.s.f.e.t. channel are about 1.7 × 107 cm/s and 1.3 × 107 cm/s, associated with Cr and Fe doped substrates, respectively.     

A 75 GHz to 115 GHz quasi-optical amplifier

A wideband quasi-optical amplifier employing two pyramidal back-to-back horns has been developed. Using a four-stage W-band low noise amplifier (LNA) designed and fabricated by Martin Marietta Laboratories, the quasi-optical amplifier gives a system gain greater than 11 dB from 86 GHz to 113 GHz without any low frequency oscillations. A peak system gain of 15.5 dB is measured at 102 GHz, and the measured noise figure of the system is 7.4 dB at 94 GHz. The quasi-optical amplifier design maintains the same polarization of the received and transmitted signal, provides better than -40 dB isolation, and can be fabricated monolithically at millimeter-wave frequencies     

S波段雷达接收机前端低噪声放大器

采用0.35μm SiGe BiCMOS工艺设计了用于S波段雷达接收机前端电路的低噪声放大器。对于现代无线接收机来说,其动态范围和灵敏度很大程度上都取决于低噪声放大器的噪声性能和线性度。相对于CMOS工艺来说,SiGe BiCMOS工艺具有更高的截止频率、更好的噪声性能和更高的电流增益,非常适合微波集成电路的设计。该低噪声放大器采用三级放大器级联的结构以满足高达30dB的增益要求。在5V的电源电压下,满足绝对稳定条件,在3GHz-3.5GHz频段内,功率增益为34.5dB,噪声系数为1.5dB,输出1dB功率压缩点为11dBm。     

Dual-gate m.e.s.f.e.t. self-oscillating X-band mixers

GaAs dual-gate m.e.s.f.e.t.s have been successfully used as self-oscillating down-convertors in X-band. A single device replaces the preamplifier, mixer and local oscillator. The best conversion gain achieved by mixing from 10 GHz down to 1 GHz was 12 dB. The input (gate 1) to output (drain) port isolation amounted to 16 dB. Slug-tuner and `disc?-resonator circuits were tested and showed comparable gain and noise performance. Best d.s.b. noise figures of 5.5 dB could be realised at an i.f. of 1 GHz with an associated conversion gain of 4 dB.     

A full W-band low noise amplifier module for millimeter-wave applications

A full W-band Low Noise Amplifier (LNA) Module is designed and fabricated in this letter. A broadband transition is introduced in this module. The proposed transition is designed, optimized based on the results from numerical simulations. The results show that 1 dB bandwidth of the transition ranges from 61 to 117 GHz. For the purpose of verification, two transitions in back-to-back connection are measured. The results show that transmission loss is only about 0.9-1.7dB. This transition is used to interface integrated circuits to waveguide components. The characteristic of the LNA module is measured after assembly. It exhibits a broad bandwidth of 75 to 110 GHz , has a small signal gain above 21 dB. The noise figure is lower than 5dB throughout the entire W-band (below 3 dB from 89 to 95GHz) at a room temperature. The proposed LNA module exhibits potential for millimeter wave applications due to its high small signal gain, low noise, and low dc power consumption     

Performance of selenium-ion-implanted GaAs f.e.t.s

Selenium-ion-implanted GaAs f.e.t.s have given minimum noise figures as low as 3·4 dB and maximum available gains of at least 10 dB at 10 GHz. The devices do not appear to suffer from short-term drift problems, and have greater device-characteristic uniformity and reproducibility than epitaxial f.e.t.s.     

Performance of self-oscillating GaAs m.e.s.f.e.t. mixers at X-band

A new mode of m.e.s.f.e.t. operation, the self-oscillating mixer is reported. Conversion gains of up to 2 dB at 10 GHz and noise figures as good as 15 dB have been demonstrated by using a simple circuit.     

A 4?8 GHz dual gate m.e.s.f.e.t. amplifier

A two-stage dual-gate f.e.t. amplifier with small signal gain of 20 ± 0.75 dB, covering an octave bandwidth (4?8 GHz) and having a dynamic gain control range in excess of 60 dB is reported. The gain frequency response, input and output v.s.w.r. are described as a function of second-gate voltage. The performance of the dual-gate f.e.t. amplifier as a fast r.f. switch is also presented.     

Broadband lumped-element X band GaAs f.e.t. amplifier

The design of a 2-stage broadband X band amplifier using GaAs Schottky field-effect transistors is described. The performance of the intrinsic device and the amplifier are summarised. The amplifier gives 9.5±1 dB gain over the frequency range 6.5?12 GHz. The v.s.w.r. at the input and the output does not exceed 2.5:1. Practical wideband matching networks are described that minimise overall amplifier noise figure and maintain a constant gain over the design bandwidth, while including the effects of parasitics, loss and discontinuity capacitances.