Monolithically Integrated 100 GHz DFB-TWEAM

A monolithically integrated distributed feedback (DFB) laser and traveling-wave electro-absorption modulator (TWEAM) with ${geq} 100$ GHz ${-}3$ dBe bandwidth suitable for Non-return-to-zero (NRZ) operation with on-off keying (OOK) is presented. The steady-state, small-signal modulation response, microwave reflection, chirp characteristic, and both data operation and transmission were investigated. The DFB-TWEAM was found to be an attractive candidate for future short distance communication in high bitrates systems.      

11 dBm photonic millimetre-wave generation at 100 GHz usinguni-travelling-carrier photodiodes

The design and characterisation of a millimetre-wave uni-travelling-carrier photodiode with a monolithically integrated matching (impedance transform) circuit utilising a coplanar-waveguide short-stub are presented. The device with the matching circuit shows ~50% higher efficiency than one with a 50 Ω load design. The maximum saturation output power obtained is 13.6 mW at 100 GHz     

Integrated antennas on Si with over 100 GHz performance, fabricated using an optimized proton implantation process

We have improved the performance of integrated antennas on Si for possible application in wireless communications and wireless interconnects. For practical VLSI integration, we have reduced the antenna size and optimized the proton implantation to a low energy of /spl sim/4 MeV with a depth of /spl sim/175 /spl mu/m. To avoid any possible contamination, the ion implantation is applied after device fabrication. Excellent performance such as very low RF power loss up to 50 GHz, record high 103 GHz antenna resonance, and sharp 5 GHz bandwidth have been achieved.     

跨越100GHz壁垒的取样器及其应用

在时域和视域测量仪器中,取样技术一直起着重要的信号捕获和变换作用,例如数字示波器的实时带宽远远不如取样示波器的等效带宽.     

An Integrated Sideband-Separating SIS Mixer Based on Waveguide Split Block for 100 GHz Band with 4.0–8.0 GHz IF

We have developed an integrated sideband-separating SIS mixer for the 100 GHz band based on the waveguide split block. The measured receiver noise temperatures with 4.0–8.0 GHz IF are less than 60 K in the LO frequency range of 90–110 GHz, and a minimum value of around 45 K is achieved at 100 GHz. The image rejection ratios are more than 10 dB in the frequency range of 90–110 GHz. We have installed the sideband-separating SIS mixer into an atmospheric ozone-measuring system at Osaka Prefecture University and successfully observed an ozone spectrum at 110 GHz in SSB mode. This experimental result indicates that the sideband-separating SIS mixer is very useful for astronomical observation as well as atmospheric observation.     

The 100 GHz light switch

Escalating transmission rates in telecoms networks are the spur behind an international research effort in optical processing. The author reports on the work of the BT researchers who are laying the foundations for a new era of photon-based switching systems. The work is based on an interferometric switch known as the TOAD. The TOAD is a variant of a Mach-Zehnder interferometer. Light enters the interferometer, then passes through a 50:50 coupler which divides the input equally between the upper and lower arms. In general, the upper and lower light streams will experience different phase shifts, and these shifts will determine the way the original input is allocated between the two output ports. In particular, if the interferometer is suitably biased then all the light will appear at one or other of the outputs. Now, if a phase shift is introduced into one of the arms the output will switch between ports. This is the principle; its practical exploitation depends on the availability of a device that can effect a π phase shift at a rate of at least tens of GHz. In the TOAD this function is assigned to a semiconductor optical amplifier     

High-speed VCSEL of modulation bandwidth over 7.0 GHz and itsapplication to 100 m PCF datalink

High-speed vertical cavity surface emitting laser (VCSEL) with 6×6 μm active area is fabricated by reducing its pad area in order to reduce its parasitic capacitance. The fabricated VCSEL shows the 3 dB bandwidth of over 7 GHz and average threshold current of 0.7 mA. This is the highest 3 dB modulation bandwidth ever reported for the plan type bottom emitted laser with pad. The maximum intrinsic bandwidth as estimated from k-factor is found to be over 20 GHz, which is less than three times than the observed bandwidth. The thermal characteristics are also found to be almost unchanged due to the reducing of its pad size. It also showed open eye pattern for 3 GHz nonreturn to zero (NRZ) pseudorandom signal after transmission through 100 m large core plastic clad fiber (PCF), which could be used in short and medium distance optical links     

Leakage currents over the Surface of CdHgTe-based photodiodes

The leakage current I _p over the surface of Cd_xHg_1−x Te-based photodiodes that have a cutoff wavelength of the photosensitivity spectrum of λ=9.8–11.6 μm and are fabricated by implanting Zn⁺⁺ ions into the p-type solid solution is investigated. The surface character of the I _p current is indicated by a coordinate shift of the peak in the sensitivity profile of n ⁺-p junctions, which is measured in a scanning mode by the beam of a CO₂ laser with a wavelength of 10.6 μm, with an increase in voltage U across the photodiode and the shift of spectral characteristics to shorter wavelengths with increasing U. __________ Translated from Fizika i Tekhnika Poluprovodnikov, Vol. 38, No. 7, 2004, pp. 890–895. Original Russian Text Copyright ? 2004 by Biryulin, Turinov, Yakimov.     

Microstrip IMPATT-diode oscillator for 100 GHz

The design and performance of a rugged duroid-microstrip IMPATT-diode oscillator is described. The oscillator's frequency was set by a simple, easily replaceable metal resonant cap, with fine tuning of about 30 MHz/mA being achieved by means of the diode current.     

Double-drift IMPATT diodes near 100 GHz

This paper reports the highestxpower (frequency)²IMPATTS produced to date. A CW output power of 380 mW has been achieved at 92 GHz with an efficiency of 12.5 percent. An all-implanted double-drift n⁺-n-p-p⁺silicon structure was fabricated, using a lightly doped epitaxial layer as the starting material. The newly made structure uses a more shallow n⁺contact than previous diodes, and therefore has more equal drift spaces. Small-signal admittance calculations show lower susceptance per unit area in the newly made structure. The shallow contact has allowed the study of unequal dopings in the n- and p-drift spaces. Unequal dopings up to 50 percent can be tolerated with less than 20 percent variation in measured efficiency and output power. Both admittance and breakdown voltage calculations based upon experimentally determined doping profiles and independently measured ionization coefficients were found to be in good agreement with experiment. The doping profiles on both sides of the depletion region were determined byC(V)analysis. The testing of both the old and new structures has been carried out in a microwave circuit having improved mechanical tuning accuracy due to the introduction of a newly designed tuning plunger.     

Groove-guide connection losses at 100 GHz

Sections of groove guide can be simply connected together with a loss of less than 0.2 dB even at 100 GHz. A gap of up to 1 mm between the sections introduced an additional loss of only about 0.1 dB and alignment tolerances needed to be no better than ±0.5 mm.     

Design of Subharmonic Mixers above 100 GHz

This paper presents the design and simulation of several fixed-tuned sub-harmonic mixers cover frequencies from 110 GH to 130 GHz, 215 GH to 235 GHz, 310 GH to 350 GHz, and 400 GH to 440 GHz. Among them, 120 GHz, 225 GHz, 330 GHz subharmonic mixers are designed with flip-chipped planar schottky diode mounted onto a suspended quartz-based substrate, the 225 GHz and 425 GHz subharmonic mixers are GaAs membrane integrated, and the 115 GHz subharmonic mixer has been fabricated and tested already.     

基于百公里量子通信实验的可移动式一体化纠缠源

利用准相位匹配技术和Sagnac环结构设计研制了一套高亮度、高稳定性、小型化、可移动式的一体化纠缠源系统.此纠缠源基于周期极化磷酸钛氧钾(PPKTP)晶体参量下转换过程,亮度达到了13.8 Mcps,偏振对比度好于98%,纠缠度达到0.9 357,温度变化和机械振动测试引起的计数率抖动小于5%.此系统成功地应用到了外场百公里量子纠缠分发和连续长时间关联速度下限测量试验中,从而为进一步实现空间纠缠源载荷提供了良好的试验技术基础.     

Integrated 460 GHz photonic transmitter module

A photonic sub-millimetre (sub-mm) wave transmitter module has been developed and fabricated. The module consists of a 1.55 μm waveguide InP photodetector monolithically integrated with a planar full wave slot antenna and passive lowpass filter for DC bias supply. For the first time, optical heterodyne 460 GHz sub-mm signal generation is demonstrated It is further shown that the module can effectively replace the classical solid-state oscillator of an astronomical superconductor-insulator-superconductor heterodyne receiver The module generates sufficient sub-mm wave power to operate the receiver under optimum conditions     

Monolithic millimetre wave ICs for 100 GHz

The primary research field of Fraunhofer-Institut Angewandte Festkörperphysik (IAF)(Applied Solid-State Physics) in Freiburg, Germany, is III–V electronics, with a focus on high-speed/high-frequency devices and integrated circuits for various applications in commercial and military systems. William Haydl, head of the MMIC group, reports on IAF's latest developments.     

Groove-guide microwave detector for 100 GHz operation

A detector has been designed and constructed, using a beam-lead diode, directly in a groove guide. A triangular dipole, produced by photolithography on RT/Duroid 5880, is placed transversely across the guide. A GEC beam-lead Schottky diode, bonded across the dipole, acts as the rectifying element. When used with a cylindrical back short-circuit and an appropriate bias current, a voltage sensitivity of about 400 VW?1 and a tangential sensitivity of about ?42 dBm was obtained at a frequency of 100 GHz.     

100GHz高增益InP基MMIC共源-共栅放大器

本文介绍了一种高增益InP MMIC共源-共栅放大器,当偏置在最大带宽时,该器件在75～100GHz下的平均增益为8.0dB;当偏置在最高增益时,80GHz下的增益高于12dB。这是目前报道的W波段(75～100GHz)增益最高的放大器。所用的有源器件是栅长为0.1μm晶格匹配的InGaAs-InAlAs高电子迁移率晶体管(HEMT)。该放大器以共面波导(CPW)作为传输线,芯片总面积为600μm×500μm。     

A Low Noise 100 GHz Sideband-Separating Receiver

We have built a 100 GHz sideband-separating receiver. The receiver, a breadboard for the band 3 cartridges for ALMA, achieves a SSB noise temperature of 6hf/k with a 4–8 GHz IF. We show that it is possible to meet the ALMA specifications. The design of the receiver is reviewed and the relationships between the receiver noise temperature and properties of the components used in the receiver are discussed.     

100 kHz~6 GHz宽带接收机设计

为解决射频信号接收系统前端因强电磁干扰而发生的互调干扰、阻塞和饱和等问题,设计基于宽带匹配网络优化了一款高效率宽带接收机。该接收机模块工作频率覆盖整个S波段,其采用4线制SPI接口,根据上位机的指令完成链路控制。除此之外,采用7阶巴特沃斯低通滤波器设计,严格保证带内最佳平坦度和端口驻波比。实测结果表明,该接收机模块实现了100 kHz~6 GHz的信号放大和下变频,并以140 MHz和100 kHz~19.999 MHz的中频输出,具备内外部10 MHz参考时基自动切换功能。可见射频接收前端优化设计可实现对目标侦测频段内信号的高选择性跟踪预选,使接收系统对强干扰信号进行有效抑制。