A 50-GHz silicon IMPATT diode oscillator and amplifier

Recent experimental observations on a silicon impact avalanche transit-time diode oscillator and amplifier CW-operated at 50 GHz are presented. 1) CW oscillation power of 100 mW was obtained at an overall efficiency of 2 percent. The oscillation frequency was continuously tunable over a 1.3-GHz range by a sliding short. 2) Phase-locking has been achieved with a maximum normalized gain-bandwidth product of 0.1. The minimum locking signal power required for a 500-MHz locking bandwidth was 20 dB below the oscillator output. 3) Electronic tuning of the oscillator frequency was demonstrated by placing a millimeter-wave varactor diode in the tuning circuit. The output frequency versus the bias voltage on the varactor diode was linear with maximum frequency deviation of 300 MHz. Frequency modulation of the oscillator by driving the varactor with a sinusoidal source was obtained at a modulation frequency of 50 MHz. 4) Stable amplification with 13-dB gain was obtained, centered at 52.885 GHz with a 3-dB bandwidth of 1 GHz. The maximum output power obtained was 16 mW. Higher gain of about 17 dB was obtained at a reduced bandwidth. The noise figure of the amplifier was 36 dB. Equivalent circuits for the oscillator and the amplifier are derived. The calculated results agree reasonably well with the experimental observations.     

Monolithic integrated circuits incorporating InP-based heterostructure barrier varactors

Fully integrated monolithic circuits incorporating InP-based heterostructure barrier varactor (HBV) frequency multipliers have been fabricated via epitaxial liftoff and transfer-substrate techniques onto a quartz substrate. We have obtained a maximum output power of 6 mW at 288 GHz: corresponding to an overall efficiency of 6%. In addition, we have observed a 45-GHz, 3-dB bandwidth centered around 300 GHz for a constant input power of 70 mW.     

W-band finite ground coplanar monolithic multipliers

This paper describes the design, fabrication, and experimental evaluation of W-band planar monolithic varactor frequency multipliers based on finite ground coplanar (FGC) lines. These lines are a low-loss low-dispersion alternative of a planar transmission line to more conventional microstrip of coplanar waveguide lines at millimeter-wave frequencies. The near transverse-electromagnetic nature of propagation of the FGC lines simplifies circuit design and layout. Two-diode W-band varactor multipliers with input Q's of two and three and FGC input and output have been realized. The multiplier with input Q=2 has an output power of 72 mW, an efficiency of 16.3% near 80 GHz, and a -3-dB bandwidth greater than 10 GHz, while the multiplier with Q=3 has an efficiency of 21.5% near 70 GHz and a 6-GHz bandwidth. This paper briefly describes the characteristics of the FGC lines, the design of the multipliers and their radiofrequency performance     

InP depletion-mode microwave MISFET's

Depletion-mode aligned-gate InP MISFET's with gate lengths of 1.5-1 µm have given output power of 1.26-W/mm gate width and power-added efficiencies of up to 40 percent at 4 GHz. At 12 GHz, 0.75-W/mm gate width with 22-percent power-added efficiency was obtained. At 18 GHz, a power output of 331 mW (0.59 W/mm) with 3.1 dB of gain and 15.7-percent power-added efficiency was measured. An output power of 245 mW (0.44 W/mm) with 3-dB gain and 10.7-percent efficiency was obtained at 20 GHz.     

High-Power Frequency Multiplier Using MIS Varactors (Short Papers)

The experiment described demonstrates the applicability of MIS varactors in microwave power circuits. A frequency doubler with 55-percent overall efficiency and pulsed output power of 5.5 W at 5.4 GHz with a duty cycle of 50 percent has been built by using two MIS varactors in parallel. The multiplier has a coaxial low-pass filter at the input and a waveguide output, allowing a 3-dB bandwidth of 8 percent.     

Advanced devices and components for the millimeter and submillimeter systems

The purpose of this paper is to discuss key topics related to low-noise mixers, high efficiency multipliers, the use of quasi-optical techniques to reduce circuit losses, and the development of very high-Q devices applicable to the millimeter and submillimeter wavelengths [1]-[5]. In particular, we will describe the development of a highly reliable metalized GaAs Ta-Schottky-barrier diode with native-oxide passivation. The zero-bias cutoff frequency of these diodes is greater than 1000 GHz when measured accurately near 60 GHz with a zero-bias junction capacitance near 0.1 pF. This zero-bias cutoff frequency is approximately twice the value for a comparable nonmetallized device. Using these very high-Q devices, we have achieved RF performance that has advanced prior state of the art. In frequency multipliers, doublers (100-200 GHz), and triplers (100-300 GHz), we have realized conversion efficiencies of 12 and 2 percent, respectively. The CW output power of the doubler was 18 mW and that of the tripler 2 mW. In an image-enhanced mixer at 35 GHz with an IF of 1 GHz, we have realized conversion loss below 3 dB including 0.6-dB circuit losses, and less than 5.9-dB noise figure (SSB) including a 2-dB IF noise-figure contribution.     

0.2 THz二倍频器研究

基于六阳极结反向串联型GaAs平面肖特基二极管,设计并实现了0.2 THz大功率二倍频器。肖特基二极管倒装焊接在50m石英电路上。采用电磁场和电路联合设计仿真获得了二倍频器的倍频效率。当入射功率在100 mW时,输出频率在190~225 GHz带内效率大于5%。在小功率（Pin100 mW）和大功率（Pin300 mW）注入条件下,测试了倍频电路的输出功率和倍频效率。在100 mW驱动功率下采用自偏压测试,最大输出功率为14.5 mW@193 GHz,对应倍频效率为14%;在300 mW驱动功率下采用自偏压测试,在188~195 GHz,输出功率大于10 mW,最大输出功率为35 mW@192.8 GHz,对应倍频效率为11%。     

A Waveguide-Cavity Multiple-Device FET Oscillator

A waveguide-cavity oscillator, applicable to power-combining circuits, has been developed using probe for coupling between active device and, cavity. No lossy stabilizing element is required. The control of output power, oscillation frequency, and injection locking bandwidth are performed easily. Output power of 44 mW and dc-RF conversion efficiency of 33.2 percent were obtained at 9.2GHz for a single-device low-power FET oscillator. A simple technique of cascading the pretuned oscillator modules was used to construct multiple-device oscillators incorporating up to four FET's with combining efficiency of about 100 percent.     

A low-voltage ultra-wideband down-conversion mixer with improved power conversion gain

This article presents a wideband mixer using a TSMC 0.18?µm complementary metal-oxide semiconductor technology process for ultra-wideband (UWB) system applications. The measured 3-dB radio frequency (RF) bandwidth is from 3 to 8.4?GHz with an intermediate frequency of 10?MHz. The measurement results of the proposed mixer achieve 8.1?dB average power conversion gain ?5?dBm input third-order intercept point (IIP3) at 7.4?GHz and 12.4–13.3?dB double side band noise figure. The total dc power consumption of this mixer including output buffers is 3.18?mW from a 1?V supply voltage. The output current buffer consumption is about 2.26?mW with an excellent local oscillator-RF isolation of up to 40?dB at 5?GHz. The article presents a mixer topology that is greatly suitable for low-power operation in UWB system applications.     

A Ka-band avalanche-diode up-converter

Operation of a silicon avalanche-diode up-converter with output frequency at 35 GHz is reported. This was done by superimposing the input signal on the dc bias while providing the diode with the LO signal. Up-conversion was achieved with about 0-dB conversion loss and output power up to 200 mW. The influence of dc bias and input frequency level is considered; the bandwidth is also shown.     

V-band high-efficiency high-power AlInAs/GaInAs/InP HEMT's

The authors report on the state-of-the-art power performance of InP-based HEMTs (high electron mobility transistors) at 59 GHz. Using a 448-μm-wide HEMT with a gate length of 0.15 μm, an output power of 155 mW with a 4.9-dB gain and a power-added efficiency of 30.1% were obtained. By power-combining two of these HEMTs, an output power of 288 mW with 3.6-dB gain and a power-added efficiency of 20.4% were achieved. This is the highest output power reported with such a high efficiency for InP-based HEMTs, and is comparable to the best results reported for AlGaAs/InGaAs on GaAs pseudomorphic HEMTs at this frequency     

Millileter-Wave Power-Combining Amplifier Using A Broadband Waveguide Combiner

A Millimeter-wave power-combining amplifier based on the multi-way rectangular-waveguide power-dividing/combining circuit has been presented and investigated. The equivalent-circuit approach has been used to analyze the passive power-dividing/combining circuits. An eight-device amplifier is designed and measured to validate the power-dividing/combining mechanism using this technique. Both the measured 10-dB return loss bandwidth and the 2-dB insertion loss bandwidth of the passive system are more than 10?GHz. The measured maximum small-signal gain of the millimeter-wave eight-device power amplifier is 22.5?dB at 26.8?GHz with a 3-dB bandwidth of more than 6?GHz, while the input and output return loss of the proposed eight-device power amplifier is around ?10?dB from 26?GHz to 36?GHz. The measured maximum output power at 1-dB compression from the power amplifier is 28 dBm at 29.5?GHz.     

Wide-Band Reflection-Type Transferred Electron Amplifiers

Stable CW and pulsed linear-reflection-type amplification at C- and X-band frequencies using epitaxial-GaAs transferred electron devices is described. These devices have a doping density-length product (nl) greater than 5 x 10/sup 11/cm/sup -2/. Criteria for avoiding the normal instabilities are discussed with specific regard for the circuit impedance, operating bias-voltage material characteristics, and the device temperature. The active impedance of a stable device has been measured, along with the effects of the package parasitic. These data were utilized to design multiple-tuned wide-band circulator-coupled coaxial-amplifier networks. Instantaneous CW bandwidths of nearly 1 octave have been measured in C-band, and instantaneous bandwidths of 4 GHz have been measured in X-band with single-stage Iinear gains from 6 to 12 dB. A -1-dB gain compression power output of 250 mW, with a saturated power output approaching 1 watt, has been realized from a single device. The noise figure of a single-stage amplifier has been found to be 15 dB. The phase response of a typical amplifier has been found to be linear with a differential phase shift of less than 20/spl deg/ /GHz. The amplitude linearity has been related to third-order intermodulation distortion and found to be comparable to that obtainable from traveling-wave-tube amplifiers (TWTAs). In a two-stage configuration a small-signal gain of 22 dB and a fractional bandwidth of 35 percent have been realized in C-band. A novel scheme for studying the gain response of pulse-biased devices using swept-frequency techniques has been developed. Pulsed amplification has been obtained with a power output of 2 watts at a 5-percent duty cycle with a conversion efficiency of 6 percent and a bandwidth of 1 GHz.     

Very large bandwidth strained MQW DFB laser at 1.3 μm

A 3-dB bandwidth of 20 GHz has been demonstrated for a compressively strained multiquantum well InGaAsP-InP DPB laser operating at 1.3 μm. The laser displayed superior static performance including very low threshold current (~8 mA), high external quantum efficiency (0.44 mW/mA), high CW output power (>60 mW) and high temperature operation     

Power measurement setup for large signal microwave characterization at 94 GHz

We report the development of a power measurement setup in order to characterize devices at 94GHz. A very careful calibration of the setup has been performed in order to take into account in a most accurate way the losses through the different parts of the bench and in particular through the tuner. These aware power measurements have allowed to demonstrate state of the art power results on two different devices. We reached at 94GHz an output power of 876mW/mm associated to a 7.5-dB power gain and a power added efficiency (PAE) of 33% on a pseudomorphic high electron mobility transistor (PHEMT) on GaAs substrate. We achieved a 260-mW/mm maximum output power density with 5.9-dB power gain and 11% PAE on an InAsP channel HEMT on InP substrate.     

2cm波段耿管电调振荡器

报道了采用部分集成方案研制的Ｋｕ波段变容管调谐耿管振荡器（ＶＣＯ）及两管功率合成器。研制的两只中心频率为１６和１７ＧＨＺ的电调振荡器，其中１６ＧＨＺ的电调带宽大于６４０ＭＨｚ，输出功率大于１１０ｍＷ，功率起伏小于０．６ｄＢ；而１７ＧＨｚ的电调带宽大于２３０ＭＨｚ，输出功率大于１１０ｍＷ，功率起伏小于０．９ｄＢ。两管功率合成器的振荡频率为１７．３ＧＨｚ，输出功率达２５０ｍＷ．     

A 100-element HBT grid amplifier

A 100-element 10-GHz grid amplifier has been developed. The active devices in the grid are chips with heterojunction-bipolar-transistor (HBT) differential pairs. The metal grid pattern was empirically designed to provide effective coupling between the HBTs and free space. Two independent measurements, one with focusing lenses and the other without, were used to characterize the grid. In each case, the peak gain was 10 dB at 10 GHz with a 3-dB bandwidth of 1 GHz. The input and output return losses were better than 15 dB at 10 GHz. The maximum output power was 450 mW, and the minimum noise figure was 7 dB. By varying the bias, a signal could be amplitude modulated with a modulation index as large as 0.65. Tests show that the grid was quite tolerant of failures-the output power dropped by only 1 dB when 10% of the inputs were detuned. The grid amplifier is a multimode device that amplifies beams of different shapes and angles. Beams with incidence angles up to 30° were amplified with less than a 3-dB drop in gain     

Fabrication and performance of GaAs p+n junction and Schottky barrier millimeter IMPATT's

A recently developed procedure, incorporating both preferential electrochemical etching for wafer thinning and electroplating for heat sink formation has been applied to the fabrication of Kaband (26.5-40 GHz) GaAs IMPATT's. Both epitaxially grown GaAs p⁺n junction and Cr Schottky barrier diodes have been fabricated. This procedure makes possible the batch fabrication of small area diodes (<2 times 10^{-5}cm²) over a large wafer area. The diodes have been operated both in the oscillator and stable-amplifier mode. Power, efficiency, and noise performance of the devices is reported. The p⁺n diodes, which could withstand junction temperature of over 300°C, gave the best power and efficiency. Powers as high as 680 mW with 12.4 percent efficiency at 34.8 GHz and an efficiency as high as 16 percent with 390 mW at 29.5 GHz have been achieved. The Cr Schottky diodes were unable to withstand junction temperatures in excess of 200°C and therefore produced less power despite the potentially better power handling capability. The highest power obtained from a Cr Schottky is 470 mW with 12.5 percent efficiency at 34 GHz. Comparable oscillator noise performance has been obtained with both types of diode. The best AM (DSB) double sideband NSR obtained is -135 dB in a 100 Hz window at 1.5 MHz from the carrier. An rms frequency deviation as low as 13 Hz in a 100 Hz window has been observed with a power output of 164 mW at 35.4 GHz by raising the external Q to 138. A lowest FM noise measure of 23 dB was achieved by reducing output power to 16 mW. The amplifier noise figure measured for both p⁺n and Cr Schottky diodes is 26 dB.     

A high-gain, low-noise 1/2-μm pulse-doped pseudomorphic HEMT

A 1/2-μm gate-length pulse-doped pseudomorphic high-electron-mobility transistor (HEMT) grown by MBE, which exhibits a current-gain cutoff frequency of 62 GHz, is discussed. The maximum available gain cutoff frequency was greater than 150 GHz. A minimum noise figure of 0.85 dB and associated gain of 14 dB were measured at 10 GHz. Tuned small-signal gain in a waveguide-to-microstrip test fixture at 44 GHz was 7.6 dB. When the HEMT was tuned for power, 260 mW/mm with 5-dB gain and 17% power-added efficiency were obtained at 44 GHz. These results suggest that a 1/2-μm pseudomorphic HEMT is a viable candidate for Q-band applications     

多阳极220GHz倍频器单片设计

介绍了一款基于GaAs肖特基二极管单片工艺的220 GHz倍频器的设计过程以及测试结果。为提高输出功率,倍频器采用多阳极结构,8个二极管在波导呈镜像对称排列,形成平衡式倍频器结构。采用差异式结电容设计解决了多阳极结构端口散射参数不一致问题,提高了倍频器的转换效率和工作带宽。对设计的倍频器进行流片、装配和测试,测试结果显示：倍频器在204～234 GHz频率范围内,转化效率大于15%;226 GHz峰值频率下实现最大输出功率为90.5 mW,转换效率为22.6%。设计的220 GHz倍频器输出功率高,转化效率高,工作带宽大。