Abstract-The effect of the companding process on QAM signals has been under investigation for the past several years. The compander, included in the PCM telephone network to improve voice performance, has an unusual affect on digital QAM data signals which are transmitted over the same channel. The quantization noise, generated by the companding process which is multiplicative (and asymmetric), degrades the detectability performance of the outermost points of the QAM constellation more than that of the inner points. The combined effect of the companding noise and the inherent white gaussian noise of the system, leads us to a re-examination of signal constellation design. In this paper we investigate the detectability performance of a number of candidates for signal constellations including, a typical rectangular QAM constellation, the same constellation with the addition of a smear-desmear operation, and two new improved QAM constellation designs with two-dimensional warpi
标签： investigation Abstract-The companding the
上传时间： 2013-12-20
上传用户：英雄
This directory builds the miniport driver for Adaptec’s 1540 family of SCSI controllers. This driver exports several functions which are used by SCSIPORT.SYS to issue SCSI requests to the devices attached to the controller, process adapter interrupts, and various other SCSI activities. This driver is also responsible for detecting non-Plug and Play 1540 SCSI controllers—the Plug and Play controllers are detected by the operating system—and for shutting down the controller during device removal or power management operations. This sample also demonstrates the use of the SCSIWMI library to add WMI functionality to SCSI miniports. This library can be linked into a miniport and provides most of the framework needed to expose WMI data blocks to SCSIPORT and the system.
标签： driver This controllers directory
上传时间： 2016-06-28
上传用户：caiiicc
M-file uses random data which BPSK modulates a carrier to configure a BPSK UWB transmitter. The receiver demodulates the BPSK UWB carrier and the data is recovered.
标签： BPSK transmitter configure modulates
上传时间： 2014-08-09
上传用户：skfreeman
Coaxial feed structures are widely used in ultra-wide band antennas . This paper modeled the characteristic of the monopole antenna feeded by coaxial line by FDTD in the time-domiain,which showes that . Firstly, it introduced the theory of the arithmetic and the particularly realization in the calculation then it described the use in the time-domain finally it analysed several characteristics of the monopole antenna. The arithmetic used in the microstrip antenna is also a quick and economical way to design the antenna.
标签： structures ultra-wide antennas Coaxial
上传时间： 2016-06-28
上传用户：朗朗乾坤
As information technology is more and more in-depth and wide range of applications, management information system has been gradually implemented in the technical maturity. Management Information System is a continuous development of new disciplines. Library Management System is a typical management information system (MIS), the development includes the background of the establishment and maintenance of database and front-end application development aspects. Database requested data consistency, integrity and the security of the data, and front-end applications require complete functions, such as easy-to-use. After analysis, I chose companies MICROSOFT VISUAL BASIC and Access prospects were as database development tools and background. With the provision of the various object-oriented development tools, in particular the data window convenient and simple objects developed intelligent customer satisfaction systems.
标签： more applications information technology
上传时间： 2013-11-29
上传用户：xymbian
Under the labor sentiment monitor system has several parts of compositions: The mobile termination software and hardware development, the central server software development as well as opens video frequency the prompt reflection. The labor sentiment monitor end is responsible for the data and the scene picture which
标签： compositions termination sentiment monitor
上传时间： 2014-11-29
上传用户：aig85
* acousticfeatures.m: Matlab script to generate training and testing files from event timeseries. * afm_mlpatterngen.m: Matlab script to extract feature information from acoustic event timeseries. * extractevents.m: Matlab script to extract event timeseries using the complete run timeseries and the ground truth/label information. * extractfeatures.m: Matlab script to extract feature information from all acoustic and seismic event timeseries for a given run and set of nodes. * sfm_mlpatterngen.m: Matlab script to extract feature information from esmic event timeseries. * ml_train1.m: Matlab script implementation of the Maximum Likelihood Training Module. ?ml_test1.m: Matlab script implementation of the Maximum Likelihood Testing Module. ?knn.m: Matlab script implementation of the k-Nearest Neighbor Classifier Module.
标签： acousticfeatures timeseries generate training
上传时间： 2013-12-26
上传用户：牛布牛
Advanced UNIX Programming is the long-awaited (19 years!) update to the 1985 original. Maybe "update" isn t the right word--of the 750-or-so pages in the new book, there are maybe two dozen paragraphs that are unchanged. The original covered about 70 system calls, and the new one covers about 300. （这是Advanced UNIX Programming的附书源码）
标签： update long-awaited Programming the
上传时间： 2013-12-19
上传用户：xiaoxiang
This programme is to control DC motor in a certain speed using PWM. The target speed is "r", it is the speed in 1s. The sample rate is 0.1s, so the actual speed target is "rc"=r/10. The "r" and "rc" are integer, and the range of "r" is from 50 to 100. Keep rc=r/10!!! The array "speed1" and "speed2" are the control result, in 0.1s and 1s. The length of "speed1" is 2400, and "speed2" is 240. The "pw" and "nw" are the parameters of PWM. The test will last 4 min.
标签： speed programme is control
上传时间： 2014-11-22
上传用户：jyycc
Already the industry standard for Python users, Programming Python from O Reilly just got even better. This third edition has been updated to reflect current best practices and the abundance of changes introduced by the latest version of the language, Python 2.5
标签： Python Programming industry standard
上传时间： 2013-12-13
上传用户：zgu489
