### 电子工程代写|电子系统工程代写Digital Systems Engineering代考|EE273

statistics-lab™ 为您的留学生涯保驾护航 在代写电子系统工程Systems Engineering方面已经树立了自己的口碑, 保证靠谱, 高质且原创的统计Statistics代写服务。我们的专家在代写电子系统工程Systems Engineering方面经验极为丰富，各种代写电子系统工程Systems Engineering相关的作业也就用不着说。

• Statistical Inference 统计推断
• Statistical Computing 统计计算
• (Generalized) Linear Models 广义线性模型
• Statistical Machine Learning 统计机器学习
• Longitudinal Data Analysis 纵向数据分析
• Foundations of Data Science 数据科学基础

## 电子工程代写|电子系统工程代写Digital Systems Engineering代考|Analogue Communication: Signals, Systems and Modulation

Communication starts with a signal. ${ }^{3}$ The simplest method of communication is visual-the policeman standing at an intersection directing traffic with signals. Another level of communication-using technology-is the concept of signals sent via Morse code over telegraph lines and received at a distant post office. This method was very popular during the 1800 s and sending a telegram was the only way to quickly send information over long distances. In the modern context, the signal in electronic communication has come to mean in particular an electrical, information- bearing signal, and the information content is voice, images or text.

The simplest signal is mathematically represented by a function of time which, for example, may be a time-varying message (like a sound signal) converted to a time-varying electrical voltage. Such an electrical signal may be represented by $x(t)$ (or $m(t)$, when we talk about a message signal). If the concept of a signal is not clear here, it will become clearer as you proceed in reading this text.

In an engineering communication system, it is important to note the following steps to convert raw information to the final signal which is made ready for communication, and after the communication process is over, to reconvert the signal back to the raw information:

1. The raw data or information which we want to transmit-which is generally analogue in nature. Most naturally occurring signals are analogue, like the diurnal temperature or $\mathrm{ECG}, \mathrm{EEG}$ or voice.
2. Conversion of the raw information to electrical signals:
(a) Conversion of the data into electrical signals, perhaps by use of a transducer. The resulting signal we call $m(t)$ for analogue communication.
(b) Conversion from $m(t)$ to $m[n]$ for digital communication.
3. Processing $m(t)$ (or $m[n]$ ) by a communication system so that it may be conveniently transmitted over a channel such as
(a) space or
(b) electrical wires or
(c) a fibre optic cable or
(d) any other medium.

## 电子工程代写|电子系统工程代写Digital Systems Engineering代考|A Typical Communication System

A communication system, in the more modern sense of the term, consists of four different blocks: a transmitter, a receiver, a channel and a source of noise. This is shown in Fig. 1.4. In this book, communication essentially will mean to be electrical communication.

If we take a look at the individual parts of a communication system, then we find that the transmitter consists of a source of information and a converter which converts the raw information into suitable electrical signals. Examples of the source of information are
(a) an audio signal,
(b) pixel values in an image and
(c) characters such as ‘ $a$ ‘, ‘ $\%$ ‘ and ‘ $L$ ‘.
These sources of information are important in that in the first case, a speech message or music may comprise the audio signal. In the second case, one may want to send a digital photograph to a friend so the individual pixels constitute the information, and so on.

The channel is the medium used for communication. The importance of the channel is that the channel properties must be such that the channel must be a ‘good’ medium to convey electrical signals and must not impede the progress of the signal which is transmitted in any manner. Examples of the channel are
(a) air,
(b) an optical cable and
(c) a coaxial line.
Each of these channels of communication has its own advantages and disadvantages.

The third block of a communication channel is the source of noise. In any communication system, noise ‘smears’ the signal in transit. Sources of noise are all those electrical sources which tend to confuse the signal being transmitted through the channel. An example of electrical noise is shown in $\mathrm{Fig}_{.} .5 .$

## 电子工程代写|电子系统工程代写Digital Systems Engineering代考|Analogue Communication: Signals, Systems and Modulation

1. 我们想要传输的原始数据或信息通常是模拟的。大多数自然发生的信号都是模拟信号，如昼夜温度或和CG,和和G或声音。
2. 将原始信息转换为电信号：
(a) 将数据转换为电信号，可能使用换能器。我们称之为结果信号米(吨)用于模拟通信。
(b) 从米(吨)至米[n]用于数字通信。
3. 加工米(吨)（或者米[n]) 通过通信系统，以便可以方便地通过诸如
(a) 空间或
(b) 电线或
(c) 光缆或
(d) 任何其他介质的通道传输。

## 电子工程代写|电子系统工程代写Digital Systems Engineering代考|A Typical Communication System

(a) 音频信号，
(b) 图像中的像素值和
(c) 字符，例如“一个 ‘, ‘ %’ 和 ‘大号’。

(a) 空气、
(b) 光缆和
(c) 同轴线。

## 广义线性模型代考

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## MATLAB代写

MATLAB 是一种用于技术计算的高性能语言。它将计算、可视化和编程集成在一个易于使用的环境中，其中问题和解决方案以熟悉的数学符号表示。典型用途包括：数学和计算算法开发建模、仿真和原型制作数据分析、探索和可视化科学和工程图形应用程序开发，包括图形用户界面构建MATLAB 是一个交互式系统，其基本数据元素是一个不需要维度的数组。这使您可以解决许多技术计算问题，尤其是那些具有矩阵和向量公式的问题，而只需用 C 或 Fortran 等标量非交互式语言编写程序所需的时间的一小部分。MATLAB 名称代表矩阵实验室。MATLAB 最初的编写目的是提供对由 LINPACK 和 EISPACK 项目开发的矩阵软件的轻松访问，这两个项目共同代表了矩阵计算软件的最新技术。MATLAB 经过多年的发展，得到了许多用户的投入。在大学环境中，它是数学、工程和科学入门和高级课程的标准教学工具。在工业领域，MATLAB 是高效研究、开发和分析的首选工具。MATLAB 具有一系列称为工具箱的特定于应用程序的解决方案。对于大多数 MATLAB 用户来说非常重要，工具箱允许您学习应用专业技术。工具箱是 MATLAB 函数（M 文件）的综合集合，可扩展 MATLAB 环境以解决特定类别的问题。可用工具箱的领域包括信号处理、控制系统、神经网络、模糊逻辑、小波、仿真等。