Introduction (chapter objectives) Complex envelopes and modulated signals Spectra of bandpass signals Nonlinear distortion · Communication circuits(mixers, phase- locked loops, frequency synthesizers, and detectors) Transmitters and receivers · Software radios

3.9 Time-Division Multiplexing Definition. Time-division multiplexing (TDM) is the time interleaving of samples from several sources so that the information from these sources can be transmitted serially over a single communication channel

Chapter Objectives Analog-to-digital signaling(PCM and delta modulation) Binary and multilevel digitals signals Spectra and bandwidths of digital signals Prevention of intersymbol interference Time division multiplexing Packet transmission

Introduction Basic signal properties(dc, rms, dBm. and power) Fourier transform and spectra Linear systems and linear distortion Bandlimited signal and sampling Discrete Fourier transform · Bandwidth of signal

Introduction Basic signal properties(dc, rms, dBm, and power) Fourier transform and spectra Linear systems and linear distortion Bandlimited signal and sampling Discrete Fourier transform Bandwidth of signal

Chapter One Introduction Why? Information Age Information Superhighway

Introduction Frequency-selective fading is a dominant impairment in mobile communications Fading reduces receive signal-to-noise ratio and degrades the bit-error-rate(BER) Frequency selectivity of the channel, i. e, delay spread, induces inter-symbol interference(ISI) To combat frequency-selective fading

第一节波形信源的统计特性和离散化 第二节连续信源和信源的信息测度 第三节具有最大熵的连续信源 第四节连续信道和波形信道的分类 笫五节连续信道和波形信道的信息传输率 笫六节连续信道和波形信道的信道容量 第七节连续信道编码定理

循环码 1、循环码的多项式描述 2、循环码的生成多项式 3、系统循环码 4、多项式运算电路 5、循环码的编码电路 6、循环码的译码 7、循环汉明码 8、缩短循环码

差错率:差错率是衡量传输质量的重要指 标之一,它有以下几种不同的定义。 码元差错率:指在传输的码元总数中发生差错的码 元数所占的比例(平均值),简称误码率。 比特差错率/比特误码率:指在传输的比特总数中发 生差错的比特数所占的比例(平均值)。在二进制 传输系统中,码元差错率就是比特差错率。 码组差错率:指在传输的码组总数中发生差错的码 组数所占的比例(平均值)