空心硅通孔的设计及其传输性能

硅通孔(TSV)能够实现信号的垂直传输,是微系统三维集成中的关键技术,在微波毫米波领域,硅通孔的高频传输特性成为研究的重点。针对微系统三维集成中,无源集成的硅基转接板的空心TSV垂直传输结构低损耗的传输要求,进行硅通孔的互连设计和传输性能分析。采用传输线校准方式,首先在硅基转接板上设计TSV阵列接地的共面波导(CPW)传输线和带TSV过孔的传输结构,并分别进行仿真分析,计算得出带TSV过孔的传输结构的插入损耗;然后通过后道TSV工艺,在硅基转接板上制作传输线和带TSV过孔的传输结构,用矢量网络分析仪法测试传输线和带TSV过孔的传输结构的插入损耗;最后计算得到单个TSV过孔的插入损耗,结果显示在0.1～30 GHz频段内其插入损耗S21≤0.1 dB,实现了基于TSV的低损耗信号传输。     

玻璃通孔的高频传输性能

随着玻璃通孔(TGV)制作工艺的成熟,微波毫米波系统采用玻璃基板进行集成,其高频传输特性成为研究的重点。对玻璃通孔的互连设计、制作和传输性能进行研究。在玻璃基板上分别设计直通传输线和带两个TGV、等长传输线的TGV传输结构;通过激光改性、腐蚀扩孔和电镀填充的TGV工艺制作技术以及薄膜电路布线技术,在玻璃基板上制作直通传输线和TGV传输结构;采用矢量网络分析仪法分别测试直通传输线和TGV传输结构的插入损耗,计算得到单个TGV的插入损耗,结果显示在33~40 GHz频段内单个TGV插入损耗S₂₁≤0.2 dB,可以满足微波毫米波系统集成应用中对玻璃基板通孔的低传输损耗要求。     

三星BSR—9300模拟卫星接收机横条干扰的检修

在ＣＡＴＶ系统中 ,传输线是传输电磁波的媒体 ,有线电视网是用同轴电缆等作为传输线把各种设备、部件连接起来而构成的电视信号传输系统。有线电视系统传输的是高频信号 ,通常为 30～ 10 0 0ＭＨｚ以上 ,它所采用的传输线是高频信号传输线 ,高频信号在传输线上是以波的形式传播的。当传输系统各部分的阻抗匹配时 ,传输线上只有入射波而没有反射波 ,此时电压(电流 )沿线分布为行波状态 ,这时入射波在传输线各处的电压幅度相等 ;反之当信号源、传输线与接收端的负载阻抗不匹配时 ,一部分信号就会由负载反射回来 ,这种反射波在返回途中和入射…     

非平行微带线间的串扰抵消研究

非平行微带线是印刷电路板(PCB)上不可避免的互连结构。针对PCB 上非平行微带线间的串扰问题,用平行微带线近似非平行微带线,把平行耦合微带线间的串扰抵消方法应用到非平行耦合微带线中,提出了利用耦合传输线信道传输矩阵方法来进行远端串扰抵消,在对非平行耦合传输线信道传输矩阵进行特征值分解的基础上构建串扰抵消电路。仿真了非平行微带线间夹角分别为q=3°、5°、10°时的串扰,结果表明,该方法可以有效改善非平行微带线上信号眼图的质量,串扰抵消效果良好。     

基于SOA的全光超宽带脉冲波形调制技术研究

提出一种基于半导体光放大器(SOA)中交叉增益调制效应(XGM)实现全光超宽带(UWB)脉冲波形调制(PSM)的新方案,只需要一个SOA,结构简单、易于集成;输出的PSM信号只含有一个波长,不需要色散介质引入时间差进行延时。利用OptiSystem7.0软件对方案进行了仿真,研究了调制信号的传输特性,并分析了各参数对调制信号的影响,得出优化范围。     

MEMS铜基微同轴传输线性能仿真及测试

研究了一种新型的MEMS超宽带铜基微同轴传输系统。设计了特性阻抗为50Ω铜基微同轴传输线结构,其仿真电压驻波比(VSWR)在DC～110 GHz内低于1.15。且设计了可用于探针台测试和芯片金丝键合的地-信号-地(GSG)转接结构,仿真插入损耗低于0.1 dB。采用该微同轴结构和GSG转接结构设计了用于探针台测试的直通-反射-传输线(TRL)校准套件,利用薄膜工艺加工得到了铜基微同轴传输线及校准件实物,通过实验测试得到该微同轴传输线DC～40 GHz最大插入损耗为0.35 dB/cm,通过仿真拟合推算其110 GHz下的插入损耗约为0.65 dB/cm,该插入损耗性能显著优于平面印刷传输线,同时,该微同轴传输线的体积远小于波导传输结构,可以用于研制小型化、高性能、高集成密度微波/毫米波系统。     

键合线互连电路的优化设计

介绍了一种微波多芯片组件中芯片与传输线互连的键合线互连电路设计。采用低通滤波器方法设计的键合线互连电路结构,在键合线长度一定的情况下,能够显著提高键合线互连电路的频率响应。设计了一种基于3阶低通滤波器的键合线互连电路,将键合线的寄生电感融入了3阶低通滤波器中,改善了键合线互连电路的微波传输特性,提高了键合线互连电路的截止频率。采用微波电路设计软件和三维电磁场软件相结合的设计方法,对键合线互连电路的微波特性进行建模、分析,验证了这种电路设计方法的正确性。     

基于集成节点的PON与OBS网络互连技术研究

无源光网络(PON)与光突发交换(OBS)网的互连是光分组传送网络发展的必然.文章分析了PON与OBS网互连存在的主要问题及已有的解决方案,提出一种聚合PON与OBS边缘节点功能的集成节点结构,研究基于集成节点的PON与0BS网络互连技术方案,提出基于业务流量的三级汇聚机制,分析结果表明三级汇聚机制可以保证业务等级,减少业务延时.     

微带线到共面波导的LTCC 宽带耦合互连过渡

在LTCC 多层电路结构中,不同形式的信号传输线之间往往采用垂直通孔互连,但由于互连通孔在高频时会 带来电感效应,且加工后会因变形而引入许多寄生参量,因此可选择耦合形式的互连过渡来实现不同传输线之间的互 连。本文针对微带线到共面波导,设计了一种可应用于LTCC 工艺的宽带耦合互连过渡结构,着重研究了耦合金属面 的宽度和耦合金属面侧边对地间隔对过渡结构频率特性的影响,并优化这些尺寸,得到了理想仿真结果：4.3GHz 到 12.7GHz 的频带内,回波损耗大于10dB,插入损耗最小到0.346dB,辐射损耗系数在小于12GHz 时,小于8.56%。     

耦合传输线信道传输矩阵建模及串扰抵消效果分析

针对高速互连系统中传输线上的串扰问题,基于电磁耦合理论,研究了耦合传输线信道传输矩阵的性质,建立了以下两种情况的耦合传输线信道传输矩阵模型及其矩阵分解形式,分别是：（1）考虑受扰线两边各一条相邻微带线对受扰线的串扰;（2）考虑受扰线两边各两条相邻微带线对受扰线的串扰.给出了上述两种情况下基于耦合传输线信道传输矩阵分解形式的串扰抵消方案,并利用仿真工具ADS对其进行了验证.结果表明：信号抖动和失真大幅下降,串扰抵消效果良好,并且第二种情况下的串扰抵消效果优于第一种情况.该结果说明了在基于耦合传输线信道传输矩阵进行串扰抵消时,考虑两边各两条相邻微带线的串扰效果较好,对保持高速信号完整性具有一定的实际应用价值.     

基于RapidIO协议的高速数据互联模块设计

RapidIO技术是目前世界上第一个、也是惟一的嵌入式系统互连国际标准,可以简单、高效、可靠地实现从单板到全系统的互连,在高性能数字信号处理系统中得到广泛的应用。介绍了基于RapidIO协议的高速数据互联模块的设计方案、高速数据传输设计中的难点、以及模块的信号完整性分析。该模块现已在雷达信号处理系统中得到应用验证,各项性能指标均能够满足应用需求,实现了可靠稳定的高速数据传输。     

Modeling and measurement of simultaneous switching noise coupling through signal via transition

The signal via is a heavily utilized interconnection structure in high-density System-on-Package (SoP) substrates and printed circuit boards (PCBs). Vias facilitate complicated routings in these multilayer structures. Significant simultaneous switching noise (SSN) coupling occurs through the signal via transition when the signal via suffers return current interruption caused by reference plane exchange. The coupled SSN decreases noise and timing margins of digital and analog circuits, resulting in reduction of achievable jitter performance, bit error ratio (BER), and system reliability. We introduce a modeling method to estimate SSN coupling based on a balanced transmission line matrix (TLM) method. The proposed modeling method is successfully verified by a series of time-domain and frequency-domain measurements of several via transition structures. First, it is clearly verified that SSN coupling causes considerable clock waveform distortion, increases jitter and noise, and reduces margins in pseudorandom bit sequence (PRBS) eye patterns. We also note that the major frequency spectrum component of the coupled noise is one of the plane pair resonance frequencies in the PCB power/ground pair. Furthermore, we demonstrate that the amount of SSN noise coupling is strongly dependent not only on the position of the signal via, but also on the layer configuration of the multilayer PCB. Finally, we have successfully proposed and confirmed a design methodology to minimize the SSN coupling based on an optimal via positioning approach.     

SiGe HBT Microprocessor Core Test Vehicle

A major impediment to the continuation of Moore's Law in the years to come is the performance of interconnections in ICs at high frequencies. Microprocessors are using a greater portion of their clock cycle charging and discharging interconnections. Silicon-germanium (SiGe) heterojunction bipolar transistors (HBTs) provide a fast track technology for the exploration of the effect of interconnections on high-speed computer design. Industry has pursued low-k dielectrics to decrease wire capacitance. Cu metallization has been used to reduce wire resistance which becomes important as the wire dimensions are scaled down. These are not the only issues for high-frequency interconnections. Some other high-frequency issues include coupling, transmission line propagation, skin effects, and dielectric and substrate loss. These phenomena cause signal attenuation, noise, and dispersion in addition to delay. In the limit of zero device delay, interconnection delay will remain in addition to these problems. Wire shortening has been possible using more layers of interconnections, but this approach may be reaching its limit. An unconventional approach, three-dimensional (3-D) integration, attempts to shorten wiring through increased circuit component placement flexibility. The approach considered here for 3-D integration uses wafer-to-wafer aligning and bonding, wafer thinning and deep, high-aspect-ratio Cu via formation. This provides an intimate interconnection between CPU components and an extremely wide path to memory that would be infeasible in conventional or multichip module packaging. This combination of SiGe HBT BiCMOS and 3-D chip stack technologies enables small computing engines in the 16-32-GHz range.     

A Three-Dimensional Stacked-Chip Star-Wiring Interconnection for a Digital Noise-Free and Low-Jitter I/O Clock Distribution Network

Cascaded repeaters are indispensable circuit elements in conventional on-chip clock distribution networks due to heavy loss characteristics of on-chip global interconnections. However, cascaded repeaters cause significant jitter and skew problems in clock distribution networks when they are affected by power supply switching noise generated by digital logic blocks located on the same die. In this letter, we present a new three-dimensional (3-D) stacked-chip star-wiring interconnection scheme to make a clock distribution network free from both on-chip and package-level power supply noise coupling. The proposed clock distribution scheme provides an extremely low-jitter and low-skew clock signal by replacing the cascaded repeaters with lossless star-wiring interconnections on a 3-D stacked-chip package. We have demonstrated a 500-MHz input/output (I/O) clock delivery with 34-ps peak-to-peak jitter and a skew of 11ps, while a conventional I/O clock scheme exhibited a 146-ps peak-to-peak jitter and a 177-ps skew in the same power supply noise environment     

基于深度学习的水下无线光通信信噪比改善研究与实现

复杂的水下环境造成了水下光信号的质量下降,为提升水下无线光通信系统信号信噪比,结合深度神经网络提出了一种信噪比改善方法,该方法通过信号频谱有效抑制了信号噪声。实验结果表明:针对1 m传输距离的水下无线光通信16阶正交振幅调制-正交频分复用(16QAM-OFDM)信号,该方法可以实现约17 dB的信噪比提升同时误码率降低至1.709×10-3,可应用于水下无线光通信系统中提升传输性能,且具备一定的泛化能力。     

The performance of MIMO system using MRT scheme in vehicular systems

In this paper an inter‐vehicle multiple‐input multiple‐output system using maximal ratio transmission (MRT) scheme is proposed, and its performance is investigated where the proposed system uses multiple antennas for transmission and reception. It has the advantage of increasing effectively the diversity order without changing the receiver. As far as we know, MRT has not been employed in vehicular systems to improve system performance. Specifically, error performance of the MRT with different number of antennas at the transmitting and receiving stations has been examined, ie, MRT (2, 1) and MRT (2, 2) in a vehicular system in which cascaded Nakagami‐m fading distribution used. First, we derive expressions of probability distribution function and then moment generating function of end‐to‐end signal‐to‐noise ratio. Based on these expressions, we obtain the symbol error rate expression on account of examining the performance of the considered system. Then, the upper bounds for the symbol error rate expressions for high enough signal‐to‐noise ratio values have been calculated. Finally, we validate the confirmation of obtained theoretical results through simulation results and furthermore show that the multiple‐input multiple‐output system using MRT scheme can provide the full diversity.      

Comprehensive Electromagnetic Modeling of On-Chip Switching Noise Generation and Coupling

A comprehensive modeling methodology is presented for the investigation of on-chip noise generation and coupling due to power switching. The backbone of the methodology is an electromagnetic model for the on-chip portion of the power grid. This allows for the impact of the displacement current density and, hence, electromagnetic retardation, to be taken into account in the accurate modeling of the power grid behavior at picosecond switching speeds. In this manner, and through the interfacing of this model with an electromagnetic model for the package portion of the power grid, which is described in terms of a multiport rational matrix transfer function, the impact of package-chip electrical interactions on switching noise can be modeled with electromagnetic accuracy. The electromagnetic model for the power grid is complemented by a resistance-capacitance model for the semiconductor substrate, which is capable of modeling local substrate induced noise coupling between neighboring circuits. Finally, distributed resistance, inductance, capacitance and conductance circuits for signal wires are extracted and used to provide for a transmission line-based modeling of crosstalk and power grid induced signal degradation. Transient simulations using the proposed comprehensive model are carried out using a hybrid time-domain integration scheme which combines a SPICE-like engine for the analysis of all circuit netlists and the nonlinear drivers incorporated in the model with a numerical integration algorithm suitable for the expedient update of the state variables in the discrete electromagnetic model for the power grid.      

Efficient wireless transmission scheme based on the recent DST-MC-CDMA

The capacity of a multicarrier code-division multiple access (MC-CDMA) system is limited by a multiple access interference (MAI) from other users. In this paper, we propose a MAI cancellation scheme to transmit images over a recent discrete sine transform (DST) based MC-CDMA (DST-MC-CDMA) system. In the proposed scheme the minimum mean square error (MMSE) equalizer is used to provide the initial estimate of users’ data and the parallel interference cancellation (PIC) scheme is then used to regenerate and cancel the MAI from the desired user. The proposed scheme is called MMSE-PIC. Simulation results in multi-path fading channel confirm the excellent performance of the proposed scheme as compared to MMSE equalization method. It is also found that the best suitable tentative decision for the proposed scheme is the null zone decision or the clipper decision. We also conduct experiments to show the performance of the proposed scheme with a real image transmission over the DST-MC-CDMA system. Results show that the proposed scheme provides significant image quality improvement as compared to the existing schemes. The average peak signal to noise ratio improvement achieved by the proposed scheme over the conventional MMSE equalizer at a SNR = 30 dB is about 6.5 dB for different number of users.     

An adaptive code position modulation scheme for wireless sensor networks

In this letter, an energy-efficient adaptive code position modulation scheme is proposed for wireless sensor networks to provide the relatively stable bit error ratio (BER) performance expected by the upper layers. The system is designed with focus on the adaptive control of transmission power, which is adjusted based on the measured power density of background noise. Interfaces among the modulation module, packet scheduling module and upper layer are provided for flexible adjustments to adapt to the background noise and deliver expected application quality. Simulations with signal processing worksystem (SPW) validate the effectiveness of the scheme.     

一种低损耗毫米波垂直互联设计

设计了一种利用球栅阵列(BGA)的毫米波垂直互联,解决了毫米波系统三维(3D)集成时层间信号互联的低损耗传输问题.根据传输线理论,利用电磁仿真软件对这种采用BGA的垂直互联进行了仿真,并对层间通孔半径、焊球半径、焊盘半径等对传输性能的影响进行了分析.样件测试结果显示,在28.4~30.4 GHz,其层间垂直传输损耗小于0.36 dB,反射小于-15 dB.该垂直互联结构简单、性能良好,可广泛用于毫米波微系统3D集成.