摘要：The design and the deposition of a rugate filter for broadband applications are *** bandwidth is extended by increasing the rugate period continuously with *** width and the smoothness of the reflection band with the distribution of the periods are *** improvement of the steepness of the stopband edges and the suppression of the side lobes in the transmission zone are realized by adding two apodized rugate structures with fixed periods at the external broadband rugate filter *** rapidly alternating deposition technology is used to fabricate a rugate filter *** measured transmission spectrum with a reflection bandwidth of approximately 505 nm is close to that of the designed broadband rugate filter except a transmittance peak in the *** on the analysis of the cross-sectional scanning electron microscopic image of the sample,it is found that the transmission peak is most likely to be caused by the instability of the deposition rate.

摘要：Beamforming using sensor array is widely used in spatial signal processing since it offers better spatial focusing capability than single sensor. However, in practical appli- cations for broadband signal, there always exists a trade-off issue between the directivity capability of an array and its robustness on system errors. In this paper, in order to combine merits of different beamformers instead of trade-off their per- formances, we propose a constrained minimum-power com- bination method. We firstly analyze two optimal beamform- ers that maximize Directivity Factor （DF） and White Noise Gain （WNG） respectively. Then we propose a non-linear combination method, which automatically selects the best beamformer that has the minimum output power, so as to control the unwanted white noise amplification and keep the maximum DF if possible. Two solutions to the proposed com- bination strategy are given. They do not need to determine the correct trade-off factor used in linear combination method, and avoid challenge ~stimations on noise and target statistics required in adaptive beamforming. The performance of the proposed beamformer is evaluated in ideal noise fields and complicated noise fields respectively. It is shown that the proposed beamformer integrates merits of different beamform- ers. It always achieves the best speech quality and biggest noise reduction compared to other popular beamformers.

摘要：A broadband class-F power amplifier for an S-band handset device is integrated on a 330.82 mm^3 die using an In Ga /GaAs HBT process. With LC serial harmonic traps immersed into the broadband output matching circuit, good harmonic suppression performance can be achieved. A pure resistive impedance of the matching circuit, but near zero at second and infinite at third harmonic frequency, which enhances the efficiency, is obtained across 1.8–2.5 GHz. Tested with a continuous wave（CW） signal, the PA delivers an output power of 34 dBm and achieves a PAE of 57% at 2 GHz. In addition, excellent harmonic suppression levels of less than –53 dBc across the second to fifth harmonic are obtained.

摘要：A broadband class-F power amplifier for multiband LTE handsets applications is developed across 2.3- 2.7 GHz. The power amplifier maintains constant fundamental impedance at the output matching circuit which is operating for broadband. The nearly zero of second harmonic impedance and nearly infinity of third harmonic impedance are found for highly efficient class-F PA. The harmonic control circuits are immersed into the broad- band output matching for fundamental frequency. For demonstration, the PA is implemented in InGaP/GaAs HBT process, and tested across the frequency range of 2.3-2.7 GHz using a long-term evolution signal. The presented PA delivers good performance of high efficiency and high linearity, which shows that the broadband class-F PA supports the multiband LTE handsets applications.

摘要：A novel design of high-efficiency broadband power amplifier （BPA） with the low-pass bias networkto enhance the efficiency and output power is presented in this paper. Compared with other bias networks, the proposed low-pass bias network shows a smaller baseband impedance, which can reduce the electrical memory effect. While it provides a larger radio frequency （RF） impedance, which can prevent the leakage of the output power from bias network. A BPA with the proposed bias network is designed using commercial GaN device Cree40025F. The designed BPA shows a fractional bandwidth of 40%, from 1.8 GHz to 2.7 GHz. The measured results exhibit 73.9 % drain efficiency （DE） value with output power of 43.5 dBm at 2.7 GHz, which appears an enhancement of 9.5% and 2.5 dBm comparing with that adopts LC bias network.

摘要：broadband sound sink/absorber via a structure with deep sub-wavelength thickness is of great and continuing interest in physics and engineering *** intuitive technique extensively used is to combine components(resonators)with quasi-perfect absorption to piece together a broad absorbing band,but the requirement of quasi-perfect absorption substantially places a very strict restriction on the impedance and thickness of the ***,we theoretically and experimentally demonstrate that a compact broadband acoustic sink that quasi-perfectly absorbs broadband arriving sound waves can be achieved with coherently coupled‘‘weak resonances"(resonant sound absorbing systems with low absorption peaks).Although each component exhibits rather low absorption peak alone,via manipulating the coherent coupling effect among the components,they collectively provide a remarkably improved performance over a wide frequency range with a significantly compressed *** illustrate the design principle,a hybrid metasurface utilizing the coaction of parallel and cascade couplings is presented,which possesses an average absorption coefficient of 0.957 in the quasi-perfect band(a>0:9)from 870 to 3224 Hz with a thickness of only 3.9 *** results open new avenues for the development of novel and highly efficient acoustic absorbers against low frequency noise,and more essentially,suggest an efficient approach towards on-demand acoustic impedance engineering in broadband.

摘要：This paper deals with the design of bidirectional coupler for broadband power line communication and the impedance matching technique with the power line. This coupler can be used for both transmitting and receiving the data, acting as transceiver. The impedance mismatching problem is also solved here using line trap circuit. The coupler circuit is capable of transmitting or receiving modulated signals with carrier frequency of 15 MHz which can be used for domestic as well as distribution power networks. Laboratory prototype tested using power line network consists of electrical household appliances and results show that the circuit is able to facilitate bidirectional band pass transmission.

摘要：Magnolia broadband近日宣布，它已和韩国主要手机制造商Pantech ＆ Curitel达成协议。由其利用Magnolia的Diversity Plus芯片组发展新型手机。Pantech ＆ Curitel将于2005年第三季把CDMA2000 EV-DO手机提供给美国电信业者以及北美、南美和亚洲其它地区的电信厂商进行测试。Magnolia是无线产业的专业IC设计公司以及天线分集射频解决方案发展商，这项合作将帮助Magnolia在美国无线市场进一步推广DiversityPlus技术。

摘要：CELL BE处理器包括一个基于PowerPC架构的控制处理单元Power Processing Element（PPE）以及8个SIMD的协处理器单元——Synergistic Processing Elements（SPEl，以及用以连接PPE，输入输出单元以及SPE的高速环形数据总线——Element Interconnect BUS（EIB）。CELLBE同时还提供了DMA指令和控制机制以用于在不同处理单元之间提供高效的通信。PPE和SPE均为RISC结构，指令字长为32位，寻址空间为64位。SPE提供最高128位宽的SIMD的数据通路。工作在3．2GHz主频下，单个SPE对8位整型可提供51．2Billion的峰值计算速度，对单精度浮点可提供25．6GFlops的峰值计算速度。

摘要：益登科技宣布，已和Magnolia broadband公司达成一项代理协议，由益登科技在中国台湾地区和大陆市场销售与代理该公司的各种手机芯片组，同时为采用这些产品的OEM厂商提供支持服务。将Magnolia的DiversityPlus芯片用于双天线手机，无线通讯业者就能以同样的无线基础设施支持两倍的用户，而不必增加基站等设施，同时还加强了手机的覆盖范围、资料速率和电池寿命。