Data Converter for Multistandard Mobile Phones

This paper describes an analog to digital converter (ADC) for mobile communication systems using a direct down conversion architecture. The ADC can be programmed to meet the requirements of different communication standards, including GSM (Global System for Mobile communication) and WCDMA (Wideband Code Division Multiple Access). The ADC is realized with a pipeline ADC architecture for WCDMA and a Sigma-Delta architecture for GSM. In order to have an optimized area and power consumption, the basic building blocks (opamps) of the converters are shared between the two converter architectures. The entire ADC consumes about 5.5 mW and occupies an active area of about 0.36 mm². A test circuit has been developed and fabricated and measurements show that both the required programmability and the required performance can be obtained using the proposed configurations.     

基于单CCCII的基带滤波器

本文提出了由单电流控制传输器（current controlled conveyor）实现的新型二阶低通滤波器，该滤波器是交流耦合，结构简单，功耗低，带宽约5MHz，适用于WCDMA的直流变频接收机。     

用FPGA实现IS-95A CDMA前向信道中的基带滤波器

介绍了IS-95A前向信道使用的基带滤波器,利用MATLAB软件对滤波器的系数量化进行了计算和仿真。FPGA的使用使得滤波器实现比较简单,而且具有高度的扩展性。     

一种基于多协议电流复用双频段压控振荡器的设计

.本文设计了一种基于IEEE 802.11 a/b/g和蓝牙多协议零中频收发机中双频段压控振荡器.该振荡器使用电流复用的方法,即将两个工作在不同频段的压控振荡器串联堆叠,达到了降低功耗的目的.通过Aglient ADS仿真,结果表明本文所设计的双频段压控振荡器功耗为12.22 mW,2.44和5.23 GHz载频处的相位噪声分别为-126.2和-120.1dBc/Hz@1 MHz,其性能完全符合IEEE 802.11a/b/g和蓝牙协议的要求.该振荡器将采用0.18 μm CMOS工艺实现,芯片面积为1.18 mm×0.67 mm.     

零中频DVB/DAB/CMMB调谐器中可编程信道滤波器设计

介绍了应用于多模多频(DVB/DAB/CMMB)移动数字电视接收的可编程信道滤波器设计.滤波器采用0.1dB波纹的7阶切比雪夫(Chebyshev)Ⅰ型低通结构,截止频率1.8/2.5/3/3.5/4 MHz可编程,在偏离截止频率1.25/4 MHz的频点上,分别实现26/57 dB衰减.多级直流负反馈环路用于抵消因版...     

移动通信用SAW滤波器发展动向

随着移动通信技术的发展.便携式电话和汽车电话设备需要各种更小、更轻并且性能有所改进的器件.SAW滤波器作为关键的高频器件.已变得越来越重要.本文慨述了SAW滤波器在移动通信中的发展动向.     

一种用于900MHz射频识别(RFID)读写器芯片的1.8VCMOS直接变频接收机

设计了针对解决900MHz RFID读写器收发机芯片中本地载波干扰问题而优化的直接变频接收机,并在0.18μm 1P6M混合信号CMOS工艺上实现验证.设计中使用了一种串联反馈结构的基带放大器以达到同时实现无源混频器输出缓冲,直流消除以及信号放大的功能.实际测量显示,该接收机的输入1dB压缩点为-4dBm,当中频信号解调信噪比要求为10dB时,可达到的灵敏度为-70dBm.该接收机与整个收发机集成在同一块芯片中,使用1.8V电源电压,工作时静态电流为90mA.     

一种基于DSP的手机音频优化方法

为了便捷、高效地对手机音频系统进行优化,这里提出了一种基于手机内核数字信号处理器（DSP）模块的实现新方法,通过软件编程实现多个级联的数字滤波器,对手机原始频率响应曲线中不达标的频段进行滤波,从而优化手机的整个音频系统。在设计滤波器的过程中应用Matlab中的函数进行仿真,可以有效地提高该方法的可靠性。应用该技术的手机通过了专门的手机音频测试,结果表明该方案可操作性强,优化效果显著。     

基带预失真线性化技术在DAB系统中的应用

通过典型的功放无记忆模型分析了功放的非线性对DAB信号所造成的失真及基带预失真技术的作用机理。介绍一种基于该机理的硬件实现，通过在数字基带对信号进行预失真处理，补偿后端的射频功放所产生的非线性幅度失真和相位失真，从而有效地改善了DAB射频功放的线性度。     

手机、无绳电话机、普通电话机的环境标志认证

中华人民共和国环境保护部颁发的《环境标志产品技术要求电话》,对手机、无绳电话机、普通电话机的环境标志认证提出技术要求,将于2011年4月1日起施行。本文主要对手机、无绳电话机和普通电话的环境标志认证背景以及环境标志认证的要求、流程、有效期等信息进行了介绍。     

A 1.8-V, 5-mA reconfigurable analog baseband circuit for low-IF multi-mode multi-band receivers

A new actively compensated amplifier suitable for replacing the positive feedback amplifier used in many active filter configurations is presented. The active compensation is achieved at the expense of only one resistor and one operational amplifier.     

基带成形滤波器的FPGA实现

针对数字化基带成形滤波的信号处理特点,将截短的基带波形进行二维分解,得到成形滤波器的多相结构。通过对多相结构的分析,给出了一种较为精简实用的基于滤波器系数查询表模式的FPGA实现结构,该结构具有实现简单、占用资源少等特点。仿真结果表明,该结构完全可以达到实际应用的要求。     

Mobile positioning for traffic state acquisition

The topics presented in this article are related to the project ‘Data Optimisation for integrated Telematics’ (Do-iT) granted by the German Ministry of Economics and Technology. Within this project the current traffic state will be derived by use of network-based data from numerous mobile phones of anonymous drivers. With respect to traditional methods such as local loop data and GPS-based floating car data (FCD), this method (floating phone data, FPD) will take advantage of area-wide availability without additional infrastructure and costs. The timing advance (TA) value and signal strength measurements to the serving antenna are available in the GSM network, as well as signal strength measurements to up to six neighbouring antennas. The TA value is used to determine the distance from the serving antenna to the mobile phone. From this a search area is generated. The position of the mobile phone is determined by use of the signal strengths, which are matched to a signal strength map. These positions are referenced to the digital road network. Positioning is used to enable a reliable traffic prediction as a base for modern traffic control and management. Within this article a brief overview of the project is given, with the main focus being on the positioning methods. Different approaches based on least squares adjustment and Kalman filtering are presented and first results from data measured in the vicinity of the city of Stuttgart are presented.     

移动终端管控系统基带板卡硬件设计与实现

移动终端管控系统是一种关联紧密的多通道信号处理系统,基带板卡是其有效保障。给出了一种DSP+ARM+FPGA多通道基带板卡设计方案,进行基带板卡硬件架构、功能和技术需求设计,对系统硬件电路进行详细设计和实现。通过测试验证了硬件设计的可行性。     

基于移动网络的手机缴纳电费系统的设计与研究

从移动运营商目前的业务现状、手机缴纳电费业务的特点及流程出发,分析了通过移动网络实现手机缴纳电费系统的实现方式、社会效益以及项目实现后需要解决的问题。     

Double‐Sharpened Decimation Filter Employing a Pre‐droop Compensator for Multistandard Wireless Applications

This paper presents a double‐sharpened decimation filter based on the application of a Kaiser and Hamming sharpening technique for multistandard wireless systems. The proposed double‐sharpened decimation filter uses a pre‐droop compensator which improves the passband response of a conventional cascaded integrator‐comb filter so that it provides an efficient sharpening performance at half‐speed with comparison to conventional sharpened filters. In this paper, the passband droop characteristics with compensation provides –1.6 dB for 1.25 MHz, –1.4 dB for 2.5 MHz, –1.3 dB for 5 MHz, and –1.0 dB for 10 MHz bandwidths, respectively. These results demonstrate that the proposed double‐sharpened decimation filter is suitable for multistandard wireless applications.     

一种基于自适应进化粒子滤波的移动机器人定位方法

提出了一种用于移动机器人定位的自适应进化粒子滤波算法.该算法利用遗传算法中的选择、交叉和变异操作改善样本的多样性,并且引入自适应调整控制参数.另外采用自适应重采样方法,只在需要时才进行重采样,减少重采样的次数.理论分析和仿真实验证明该算法能有效地提高定位精度.     

Building a Platform to Bridge Low End Mobile Phones and Cloud Computing Services

Two waves of technology are dramatically changing daily life: cloud computing and mobile phones. New cloud computing services such as webmail and content rich data search have emerged. However, in order to use these services, a mobile phone must be able to run new applications and handle high network bandwidth. Worldwide, about 3.45 billion mobile phones are low end phones;they have low bandwidth and cannot run new applications. Because of this technology gap, most mobile users are unable to experience cloud computing services with their thumbs. In this paper, a novel platform, Thumb-in-Cloud, is proposed to bridge this gap.Thumb-in-Cloud consists of two subsystems: Thumb-Machine and Thumb-Gateways. Thumb-Machine is a virtual machine built into a low end phone to enable it to run new applications. Thumb-Gateways can tailor cloud computing services by reformatting and compressing the service to fit the phone' s profile.     

基带信号QPSK调制与脉冲成型滤波器ASIC实现

WCDMA基带处理器上行方向采用QPSK调制方式与根升余弦脉冲成型滤波器产生3GPP WCDMA协议25.213 Release6中规定的基带信号.文章介绍了QPSK调制与此同时脉冲成型的基本原理,并给出了该调制方式与成型滤波器的ASIC设计.     

高形状因子可编程微波光子滤波器集成芯片

为了适应新型通信技术发展,该文提出了一种高形状因子、可编程的微波光子滤波器集成芯片。该滤波器芯片采用绝缘体上硅材料(SOI),利用有限冲击响应原理,通过调节各支路上的热光调制器,可以实现带宽可调、形状因子大于0.55的滤波曲线,以及中心频率可调、带宽可调和滤波形状可变3种不同滤波功能。该滤波器尺寸小、重量轻、灵活性高,能适用于大带宽信号处理,并能提供一种理想的信道划分方式,可广泛应用于国防领域和5G网络中。