基于零偏置肖特基二极管的270 GHz高性能波导检波器

根据InP二极管的物理结构, 采用三维高频电磁仿真软件对其精确建模仿真, 获得二极管的物理模型和匹配电路的精确参数, 而后将此模型利用谐波平衡进行仿真设计.最后, 在此基础上采用InP肖特基二极管, 设计制作并测试了国内首款270GHz的零偏置检波器.检波器的最大电压响应度为1600V/W, 在260~280GHz范围内, 电压响应的典型值为1400V/W, 其对应的等效噪声功率典型值为18pW/Hz.实验结果与仿真结果比较吻合, 其结果表明, 设计方法较为精确, 具有设计简单、优化方便等优点.     

基于零偏置肖特基二极管的270GHz高性能波导检波器（英文）

根据InP二极管的物理结构,采用三维高频电磁仿真软件对其精确建模仿真,获得二极管的物理模型和匹配电路的精确参数,而后将此模型利用谐波平衡进行仿真设计.最后,在此基础上采用InP肖特基二极管,设计制作并测试了国内首款270 GHz的零偏置检波器.检波器的最大电压响应度为1600 V/W,在260~280 GHz范围内,电压响应的典型值为1400 V/W,其对应的等效噪声功率典型值为18 pW/槡Hz.实验结果与仿真结果比较吻合,其结果表明,设计方法较为精确,具有设计简单、优化方便等优点.     

基于平面肖特基二极管的W波段检波器

肖特基二极管技术为常温下毫米波信号的检测提供了有效的解决方案。它具有极低的寄生电容和级联电阻,可用于该频段的倍频器、混频器和检波器当中。相比于Galey Cell和热辐射测定器(Bolometer),基于肖特基二极管的直接检波技术具有低噪声、高反应率和常温使用的特点。本文介绍了一种基于波导结构的零偏置肖特基二极管检波器,采用E面探针传输波导基模电磁波,通过阻抗匹配实现微带线到二极管的耦合。测试结果表明,在-30 dBm输入功率下：电压反应率的峰值可达8 900 V/W;在75 GHz~105 GHz的频率范围内,电压反应率在1 000 V/W以上。     

W波段混合集成高速脉冲检波器

基于混合集成技术,利用HSCH-9161梁式引线检波二极管,成功研制了一种w波段高速脉冲检波器.为了满足检波器实验测试的需要,设计了同波段的高速脉冲调制器,其采用典型的单刀单掷开关电路结构.实验测试得到:在92～98GHz工作频带内,调制脉冲信号上升时间为700ps时,连续波信号源经调制和检波后输出脉冲络的上升时间为2ns～3ns.实验测试表明,该检波器工作频率高、响应速度快,可应用于W波段脉冲检测系统.     

0.14 THz 10 Gbps无线通信系统

太赫兹通信由于其固有的宽带特性,在Gbps以上的高速无线通信领域受到广泛关注。本文描述了一种工作在0.14 THz频段的无线通信系统,传输速率达10 Gbps。该系统基于超外差结构,中频采用数字信号处理技术进行16QAM高阶数字信号调制解调,依靠肖特基二极管次谐波混频技术实现从中频到太赫兹信号的频谱搬移。目前该系统已经通过了500 m 10 Gbps距离无线传输实验验证,通信频段为133.8 GHz～137.4 GHz,带宽3.6 GHz,发射功率0 dBm,传输误码率低于10-6。     

W 波段宽带高灵敏度功率检波器

在对肖特基二极管等效电路模型精确建模的基础上,设计并制作了W 波段宽带高灵敏度功率检波器。根据GaAs 低势垒肖特基二极管的物理结构,建立了二极管等效电路模型,并通过对W 波段检波器试验模块的研制和测试提取了准确的电路模型参数。最后,针对宽带工作要求,根据二极管等效电路模型,优化了射频阻抗匹配网络,使检波器工作频率能够覆盖78～98 GHz。测试结果表明,当输入功率为-30 dBm 时,82 GHz 处检波灵敏度达到了7000 mV/ mW,78～98 GHz 范围内检波灵敏度高于1500 mV/ mW,实测正切灵敏度优于-36 dBm。实测和仿真结果一致,验证了二极管等效电路模型的准确性。     

基于混频偏置合成的高速太赫兹无线通信系统

提出一种基于载波抑制混频与载波偏置功率合成的高速太赫兹无线通信方案。发射端利用载波抑制混频器和载波偏置功率合成在140 GHz载波上实现了开关键控(OOK)调制;接收端利用包络检波接收器进行检波接收。分别开展了不同混频本振功率及偏置功率下的检波响应实验、不同基带信号功率及偏置功率下的检波响应实验,以及不同输入功率下的检波响应实验。实验结果对OOK调制器设计,以及OOK类通信系统的优化均具有较好的指导意义。最后,利用优化的系统参数在70 cm距离上实现了140 GHz, 16 Gbps的无线通信,系统误码率(BER)优于10-5。     

（英）一种基于透镜天线的宽带太赫兹准光检波器

设计了一种能够工作在140~325 GHz频带的宽带准光检波器,由一颗高阻硅透镜和单片集成检波芯片组成.设计并加工出双缝天线,在天线馈电端集成了肖特基二极管,该紧凑结构使其能够接收空间中的太赫兹辐射并转换为基带信号.为增强片上天线的方向性,利用MLFMM算法进行了扩展半球硅透镜的设计和优化,实现了良好的辐射特性.通过测试,天线在220 GHz和324 GHz处的辐射增益分别为26 dB和28 dB.在140~325 GHz,检波器测试得到的响应率可达到1 000~4 000 V/W,对应的等效噪声功率(NEP)估算为0.68~273 pW/Hz.     

一种基于透镜天线的宽带太赫兹准光检波器（英文）

设计了一种能够工作在140~325 GHz频带的宽带准光检波器,由一颗高阻硅透镜和单片集成检波芯片组成.设计并加工出双缝天线,在天线馈电端集成了肖特基二极管,该紧凑结构使其能够接收空间中的太赫兹辐射并转换为基带信号.为增强片上天线的方向性,利用MLFMM算法进行了扩展半球硅透镜的设计和优化,实现了良好的辐射特性.通过测试,天线在220 GHz和324 GHz处的辐射增益分别为26 dB和28 dB.在140~325 GHz,检波器测试得到的响应率可达到1 000~4 000 V/W,对应的等效噪声功率(NEP)估算为0.68~2.73pW/Hz(1/2).     

基于肖特基变容二极管的0.17 THz 二倍频器研制

研制了一种基于肖特基变容二极管的0.17 THz 二倍频器, 该器件为0.34 THz 无线通信系统收发前端提供了低相噪、低杂散的本振信号.倍频器结构基于波导腔体石英基片微带电路实现, 其核心器件是多结正向并联的肖特基变容二极管.文中采用结参数模型和三维电磁模型相结合的方式对二极管进行建模, 通过两种电路匹配方式实现了0.17 THz 二倍频器的最优化设计, 最终完成器件的加工及测试.测试结果表明, 在输入80~86 GHz, 20 dBm 的驱动信号下, 倍频器的最大输出功率达12.21 mW, 倍频效率11%, 输出频点为163 GHz;当前端输入功率达到饱和状态时, 该频点输出功率可达21.41 mW.     

Fabrication of 40 Gb/s Front‐End Optical Receivers Using Spot‐Size Converter Integrated Waveguide Photodiodes

We fabricated 40 Gb/s front‐end optical receivers using spot‐size converter integrated waveguide photodiodes (SSC‐WGPDs). The fabricated SSC‐WGPD chips showed a high responsivity of approximately 0.8 A/W and a 3 dB bandwidth of approximately 40 GHz. A selective wet‐etching method was first adopted to realize the required width and depth of a tapered waveguide. Two types of electrical pre‐amplifier chips were used in our study. One has higher gain and the other has a broader bandwidth. The 3 dB bandwidths of the higher gain and broader bandwidth modules were about 32 and 42 GHz, respectively. Clear 40 Gb/s non‐return‐to‐zero (NRZ) eye diagrams showed good system applicability of these modules.     

SiGe clock and data recovery IC with linear-type PLL for 10-Gb/sSONET application

An integrated 10 Gb/s clock and data recovery (CDR) circuit is fabricated using SiGe technology, It consists of a linear-type phase-locked loop (PLL) based on a single-edge version of the Hogge phase detector, a LC-tank voltage-controlled oscillator (VCO) and a tri-state charge pump. A PLL equivalent model and design method to meet SONET jitter requirements are presented. The CDR was tested at 9.529 GB/s in full operation and up to 13.25 Gb/s in data recovery mode. Sensitivity is 14 mV_pp at a bit error rate (BER)=10^-9 . The measured recovered clock jitter is less than 1 ps RMS. The IC dissipates 1.5 W with a -5 V power supply     

用于SDH STM-64光发射机的GaAs PHEMT激光驱动器

介绍了用于SDH系统STM-64速率光发射机用的激光二极管/光调制器驱动器集成电路的设计。电路采用法国OMMIC公司的0.2μm GaAs PHEMTs工艺设计并制造,可以驱动激光二极管和电吸收式调制器。电路由输入匹配电路、预放大电路、源极跟随器、主放大电路、电容耦合电流放大器和输出电路组成。电路芯片面积1.0mm×0.9mm。测试结果表明,电路采用单一正5V电源供电,直流功耗1.4W,可以在10Gb/s速率下正常工作,眼图良好。最高工作速率高于20Gb/s,输出电压幅度2.8V。     

High-performance antimonide-based heterostructure backward diodes for millimeter-wave detection

Small-area antimonide-based backward diodes for zero-bias millimeter-wave detection have been fabricated and tested. The devices were fabricated using high-resolution I-line stepper lithography, allowing accurate control of the small device active area required for operation at W-band. The devices exhibit excellent measured performance from 1-110 GHz, with responsivities when driven from a 50-/spl Omega/ source of 2540 V/W at 95 GHz. This translates to a projected responsivity of 11.5 /spl times/ 10/sup 3/ V/W at 95 GHz for a conjugately matched detector. The compression characteristics of the detectors have been measured, with 1.2 dB of responsivity compression for an input power of 8 /spl mu/W.     

20 GHz bandwidth InGaAs photodetector for long-wavelength microwave optical links

InGaAs photodetectors have been fabricated having a packaged RC plus transit-time-limited bandwidth of 20 GHz and a fibre-coupled responsivity of 0.55 A/W. Using a directly modulated InGaAsP diode laser, the photodetector optical frequency response was measured 3 dB flat to 17 GHz, the bandwidth limit of the laser.     

High-Speed Coplanar Waveguide Based Submount for 40 Gbit/s Electroabsorption Modulator

A high-speed submount has been designed and fabricated for 40 Gb/s electroabsorption (EA) modulators. The submount contains a coplanar waveguide (CPW) for microwave signal feeding and a Ta₂N thin-film resistor for impedance matching. The CPW transmission line is designed to ensure low microwave loss and reflection, and Ti/Cu/Ni/Au metal is adopted for electrode fabrication to guarantee good contact with the Ta₂N thin-film. The typical reflection coefficient of fabricated submount is estimated to be lower than?21 dB up to 40 GHz. As a demonstration, a high-speed EA modulator was chip-level packaged using the high-speed submount, and the measured small-signal modulation bandwidth was over 40 GHz.     

Evanescent-Coupled Ge p-i-n Photodetectors on Si-Waveguide With SEG-Ge and Comparative Study of Lateral and Vertical p-i-n Configurations

Si-waveguide-integrated lateral Ge p-i-n photodetectors using novel Si/SiGe buffer and two-step Ge-process are demonstrated for the first time. Comparative analysis between lateral Ge p-i-n and vertical p-Si/i-Ge/n-Ge p-i-n is made. Light is evanescently coupled from Si waveguide to the overlaying Ge- detector, achieving high responsivity of 1.16 A/W at 1550 nm with f_{3 dB} bandwidth of 3.4 GHz for lateral Ge p-i-n detector at 5 V reverse bias. In contrast, vertical p-Si/i-Ge/n-Ge p-i-n has lower responsivity of 0.29 A/W but higher bandwidth of 5.5 GHz at -5 V bias. The higher responsivity of lateral p-i-n detectors is attributed to smaller optical mode overlap with highly doped Ge region as in vertical p-i-n configuration.     

Zero bias resonant tunnel Schottky contact diode for wide-band direct detection

A Schottky-collector resonant tunnel diode detector has been fabricated and characterized at zero bias up to 400 GHz. General device structure and fabrication are discussed, and small-signal equivalent models are presented for different diode areas. Over the measured range of 200 to 400 GHz using a monolithic antenna structure, noise equivalent power values between 3-8 pW/Hz/sup 1/2/ are achieved. The current-voltage characteristics of the diode show weak temperature dependence over a measured range of 213-323 K.