The combinatorial core of the OVSF code assignment problem that arises in UMTS is to assign some nodes of a complete binary tree of height h (the code tree) to n simultaneous connections, such that no two assigned nodes (codes) are on the same root-to-leaf path. Each connection requires a code on a specified level. The code can change over time as long as it is still on the same level. We consider the one-step code assignment problem: Given an assignment, move the minimum number of codes to serve a new request. Minn and Siu proposed the so-called DCAalgorithm to solve the problem optimally. We show that DCA does not always return an optimal solution, and that the problem is NP-hard. We give an exact nO(h)-time algorithm, and a polynomial time greedy algorithm that achieves approximation Ratio Θ(h). Finally, we consider the online code assignment problem for which we derive several results
标签： combinatorial assignment problem arises
上传时间： 2014-01-19
上传用户：BIBI
The software is capable to simulate space time code [1] for QPSK modulation using different number of state. Examples of generator matrix up to 256 stetes are provided. Variable signal to noise Ratio (SNR) might be applied to produce bit error rate (BER) or frame error rate (FER) curves.
标签： modulation different software simulate
上传时间： 2014-01-21
上传用户：qq1604324866
In this project we analyze and design the minimum mean-square error (MMSE) multiuser receiver for uniformly quantized synchronous code division multiple access (CDMA) signals in additive white Gaussian noise (AWGN) channels.This project is mainly based on the representation of uniform quantizer by gain plus additive noise model. Based on this model, we derive the weight vector and the output signal-to-interference Ratio (SIR) of the MMSE receiver. The effects of quantization on the MMSE receiver performance is characterized in a single parameter named 鈥漞quivalent noise variance鈥? The optimal quantizer stepsize which maximizes the MMSE receiver output SNR is also determined.
标签： mean-square multiuser receiver project
上传时间： 2014-11-21
上传用户：ywqaxiwang
We analyze, both analytically and numerically, the effectiveness of cloaking an infinite cylinder from observations by electromagnetic waves in three dimensions. We show that, as truncated approximations of the ideal permittivity and permeability tensors tend towards the singular ideal cloaking fields, so that the anisotropy Ratio tends to infinity, the D and B fields blow up near the cloaking surface. Since the metamaterials used to implement cloaking are based on effective medium theory, the resulting large variation in D and B will pose a challenge to the suitability of the field averaged characterization of " and 碌. We also consider cloaking with and without the SHS (softand- hard surface) lining, shown in [6] to be theoretically necessary for cloaking in the cylindrical geometry. We demonstrate numerically that cloaking is significantly improved by the SHS lining, with both the far field of the scattered wave significantly reduced and the blow up of D and B prevented.
标签： effectiveness analytically numerically cloaking
上传时间： 2017-03-30
上传用户：zxc23456789
This application report discusses the design of non-invasive optical plethysmography also called as pulsoximeter using the MSP430FG437 Microcontroller (MCU). The pulsoximeter consists of a peripheral probe combined with the MCU displaying the oxygen satuRation and pulse rate on a LCD glass. The same sensor is used for both heart-rate detection and pulsoximetering in this application. The probe is placed on a peripheral point of the body such as a finger tip, ear lobe or the nose. The probe includes two light emitting diodes (LEDs), one in the visible red spectrum (660nm) and the other in the infrared spectrum (940nm). The percentage of oxygen in the body is worked by measuring the intensity from each frequency of light after it transmits through the body and then calculating the Ratio between these two intensities.
标签： plethysmography non-invasive application discusses
上传时间： 2014-01-17
上传用户：天诚24
This project features a full-hardware sound compressor using the well known algorithm: IMA ADPCM. The core acts as a slave WISHBONE device. The output is perfectly compatible with any sound player with the IMA ADPCM codec (included by default in every Windows). Includes a testbench that takes an uncompressed PCM 16 bits Mono WAV file and outputs an IMA ADPCM compressed WAV file. Compression Ratio is fixed for IMA-ADPCM, being 4:1. PLEASE NOTICE THAT THIS CORE IS LICENSED UNDER http://creativecommons.org/licenses/by-nc-sa/3.0/ (Creative Commons Attribution-Noncommercial-Share Alike 3.0 Unported). That means you may use it only for NON-COMMERCIAL purposes.
标签： full-hardware compressor algorithm features
上传时间： 2014-01-14
上传用户：Shaikh
This file is a function under matlab which allow to compute and plot Amplitude modulation : AM. We can observe the effect of the information parameter can be changed such as amplitude and modulation Ratio m.
标签： modulation Amplitude function compute
上传时间： 2017-06-26
上传用户：cooran
The MINI2440 is an effecient ARM9 development board with a comprehensive price, it characterizes simple method and high performance-price Ratio. Based on the Samsung S3C2440 microprocessor, it embodies professional stable CPU core power source chip and reset chip to ensure the stability of the system opeRation. The PCB on the MINI2440 board is designed to be 4-layers board, adopting the ENIG technology and professional equal-length wiring to ensure the completeness of the signals of the key signal wires and manufactured and released under stringent quality control plans. With the help of this detailed manual, users are supposed to become proficient in the development process of embedded Linux and WinCE operating system, they are supposed to get the foundation, so long as they have obtained the basic and necessary knowledge about the C language, in two weeks.
标签： comprehensive characterizes development effecient
上传时间： 2013-12-18
上传用户：csgcd001
In 揚erformance of multi-carrier DS CDMA Systems?we apply a multi-carrier signaling technique to a direct-sequence CDMA system, where a data sequence multiplied by a spreading sequence modulates multiple carriers, rather than a single carrier. The receiver provides a correlator for each carrier, and the outputs of the correlators are combined with a maximal-Ratio combiner. This type of signaling has the desirable properties of exhibiting a narrowband interference suppression effect, along with robustness to fading, without requiring the use of either an explicit RAKE structure or an interference suppression filter.
标签： multi-carrier erformance signaling technique
上传时间： 2017-07-31
上传用户：宋桃子
Aodv for NS-2. A mobile ad-hoc network (MANET) is a kind of wireless ad-hoc network, and is a self-configuring network of mobile routers connected wirelessly. MANET may operate in a standalone fashion, or may be connected to the larger Internet. Many routing protocols have been developed for MANETs over the past few years. This project evaluated three specific MANET routing protocols which are Ad-hoc On-demand Distance Vector (AODV), Dynamic Source Routing (DSR) and Dynamic MANET Ondemand routing protocol (DYMO) to better understand the major characteristics of these routing protocols. Different performance aspects were investigated in this project including packet delivery Ratio, routing overhead, throughput and average end-to-end delay.
标签： network ad-hoc wireless mobile
上传时间： 2014-01-11
上传用户：zsjzc
