软件无线电中的射频与数字信号处理：多标准多模式方法

需积分: 10 75 浏览量更新于2024-07-21 收藏 2.48MB PDF 举报

"《RF and Digital Signal Processing for Software-Defined Radio》是关于软件无线电中射频与数字信号处理的专业书籍，中文译名为《软件无线电中的射频与数字信号处理》。这本书以其多标准、多模式的方法论，为工程技术人员提供了实用的参考指南。" 在软件无线电领域，射频（RF）和数字信号处理（DSP）是两个至关重要的概念。软件无线电技术是一种革命性的通信方法，它允许通过软件来实现传统上由硬件完成的许多无线通信功能。这本书深入探讨了这两个领域，旨在帮助读者理解和应用软件无线电的核心技术。 RF部分主要涉及以下知识点： 1. 射频系统的基本原理：包括射频信号的产生、放大、调制和解调过程，以及射频前端的设计。 2. 射频硬件：涵盖混频器、滤波器、振荡器、放大器等关键组件的工作原理和设计考虑。 3. 射频接收机和发射机架构：讨论不同类型的接收机和发射机设计，如超外差接收机和直接转换接收机。 4. 射频干扰和噪声处理：介绍如何在射频链路中减少噪声和提高信噪比。数字信号处理部分涵盖了以下内容： 1. 数字信号处理基础：包括离散时间信号、数字滤波器理论、采样定理和数字信号处理算法。 2. 信号调制与解调：详细讲解各种数字调制技术，如QPSK、QAM和OFDM，并阐述其在软件无线电中的实现。 3. 多载波通信：重点讨论OFDM（正交频分复用）系统，这是现代无线通信系统中广泛使用的一种技术。 4. 软件定义无线电中的同步和信道估计：这些是确保数据正确传输的关键步骤，书中会介绍相关的算法和实现策略。 5. 频谱感知和认知无线电：讨论软件无线电在频谱效率提升和动态频谱接入方面的应用。此外，书中可能还涵盖了多标准兼容性、错误检测与纠正编码、信号检测和分类、以及实时 DSP 实现等主题。通过这些内容，读者能够获得构建和优化软件无线电系统所需的知识和技能，以适应不断变化的通信环境和标准。

www.newnespress.com

3Introduction

conversion closer to the antenna. However, more digital signal processing should by

no means imply that the radio is any easier to design or that IF-sampling is superior to

quadrature sampling. All it means is that IF-sampling architecture could possibly afford

more ﬂ exibility in supporting multiple waveforms and services at a reasonable cost and

complexity. Furthermore, IF-sampling architecture does not imply that the ensuing design

becomes any less complicated or any more robust!

As a matter of fact, the added ﬂ exibility of the radio serves to add to its complexity,

especially when dealing with coexistence scenarios and interference mitigation.

However, the advantage of SDR over traditional solutions stems from its adaptability to

its environment and the number and type of application that it can support. This can be

accomplished since the hardware itself and its operation is abstracted completely from

the software via a middleware layer known as the hardware abstraction layer (HAL). The

purpose of the HAL is to enable the portability and the reusability of software [3] . This

common framework enables the development and deployment of various applications

without any dependencies on the particular radio hardware.

The SDR concept further assumes certain smarts in the antenna, the RF, and the DSP. In

the case of the antenna, this is manifested in terms of its ﬂ exibility to tuning to various

bands, and its adaptability in terms of beamforming (self-adapting and self-aligning),

MIMO operations, and interference rejection (self-healing). Obviously these aims,

when it comes to the antenna, are much easier said than done. In terms of analog and

digital signal processing, the SDR manages the various stages of the RF to make it more

adaptable to its ever-changing environment in order to achieve the desired QoS. Likewise,

this ﬂ exibility is extended to the data conversion mixed-signal blocks that are conﬁ gured

to receive the desired signal. This entails changing the sampling rate of the converter and

its resolution depending on the environment (e.g., blockers, interferers, IF frequency,

etc.) and the signaling scheme in a scalable, power-efﬁ cient manner that guarantees

adequate performance. The digital signal processing is also conﬁ gured and programmed

to complement the RF in terms of ﬁ ltering, for example, and to perform the various

modem functionalities. The modem is designed to support multiple waveforms employing

various data rates and modulation schemes (e.g., spread spectrum, OFDM, etc.). In

most applications, this is done using a ﬁ eld programmable gate array (FPGA) with

application speciﬁ c capabilities. This endows the radio with real-time reconﬁ guration

and reprogramming capacity, which allows it to roam over various networks in different

geographical regions and environments supporting multiple heterogeneous applications.

www.newnespress.com

Chapter 1

The efﬁ cient implementation of such a radio relies on robust common hardware

platform architectures and design principles as deﬁ ned and outlined in the Software

Communication Architecture (SCA) standard supported by the SDR forum and adopted

by the Joint Program Ofﬁ ce (JPO).

1.3 Software Requirements and Reconﬁ gurability

Current SDR implementations mostly rely on reconﬁ gurable hardware to support a

particular standard or waveform while the algorithms and the various setups for other

waveforms are stored in memory. Although application-speciﬁ c integrated circuits lead to

the most efﬁ cient implementation of a single-standard radio, the same cannot be said when

addressing a multi-mode multi-standard device. For a device with such versatility, the ASIC

could prove to be very complex in terms of implementation and inefﬁ cient in terms of cost

and power consumption. For this reason, SDR designers have turned to FPGAs to provide

a ﬂ exible and reconﬁ gurable hardware that can support complex and computationally

intensive algorithms used in a multitude of voice, data, and multimedia applications.

In this case, one or more FPGAs are typically used in conjunction with one or more

DSPs, and one or more general-purpose processors (GPPs) and/or microcontrollers to

simultaneously support multiple applications. FPGAs are typically conﬁ gured at startup

and with certain new architectures can be partially conﬁ gured in real time. Despite all

of their advantages, however, the industry still has not adopted FPGA platforms for

use in handheld and portable devices due to their size, cost, and power consumption.

Similarly, DSPs and GPPs can also be programmed in real time from memory, allowing

for a completely ﬂ exible radio solution. Unlike dedicated DSPs used in single standard

solutions, SDR employs programmable DSPs that use the same computational kernels for

all the baseband and control algorithms.

1.4 Aim and Organization of the Book

The aim of this book is to provide the analog and digital signal processing tools necessary

to design and analyze an SDR. The key to understanding and deriving the high-level

requirements that drive the radio speciﬁ cations are the various waveforms the radio

intends to support. To do so, a thorough understanding of common modulation waveforms

and their key characteristics is necessary. These high level requirements are then

disseminated onto the various radio blocks, namely the antenna, the RF, the mixed-signal

www.newnespress.com

5Introduction

data conversion (ADC and DAC) blocks, and the digital signal processing block. Of

course there are other key components related to the various processors and controllers,

and the software and middleware. These topics are beyond the scope of this book.

The book is divided into four sections presented in ten chapters. Section 1 is comprised

of Chapters 2 and 3. Chapter 2 deals with analog modulation techniques that are still

relevant and widely in use today. Spectral shaping functions and their implementations

are also discussed in detail. Chapter 3 addresses digital modulation schemes ranging from

simple M -PSK methods to spread spectrum and OFDM. In both chapters ﬁ gures of merit

and performance measures such as SNR and BER under various channel conditions are

provided.

Section 2 deals mainly with the RF and analog baseband. This section is divided into

three chapters. Chapter 4 addresses the basics of noise and link budget analysis. Chapter

5 deals with nonlinearity speciﬁ cations and analysis of memoryless systems. Design

parameters such as second and third order input-referred intercept points, intermodulation

products, harmonics, cross-modulation, and adjacent channel linearity speciﬁ cations are a

few of the topics discussed. Similarly, Chapter 6 further addresses RF and analog design

principles and analysis techniques with special emphasis on performance and ﬁ gures of

merit. Topics include receiver selectivity and dynamic range, degradation due to AM/AM

and AM/PM, frequency accuracy and tuning, EVM and waveform quality factor and

adjacent channel leakage ratio are among the topics discussed.

Section 3 addresses sampling and data conversion. This section is comprised of Chapters

7, 8, and 9. In Chapter 7, the basic principles of baseband and bandpass sampling are

studied in detail. The resolution of the data converter as related to sampling rate, effective

number of bits, peak to average power ratio, and bandwidth are derived. The chapter

concludes with an in-depth analysis of the automatic gain control (AGC) algorithm.

In Chapter 8, the various Nyquist sampling converter architectures are examined in

detail. Particular attention is paid to the pros and cons of each architecture as well as the

essential design principles and performance of each. Chapter 9 discusses the principles

of oversampled data converters. The two main architectures, namely continuous-time and

discrete-time ΔΣ -modulators, are examined in detail. Again, the various pros and cons of

each method are presented.

Section 4 consists of Chapter 10. Chapter 10 introduces the basics of multirate signal

processing techniques such as interpolation and decimation. A detailed study of the

剩余395页未读，继续阅读

lmwxj

粉丝: 0
资源: 1

软件无线电中的射频与数字信号处理：多标准多模式方法

RF and Digital Signal Processing for Software-Defined Radio

RF and Digital Signal Processing for Software Defined Radio

Software_Defined_Radio_using_MATLAB_Simulink_and_the_RTL-SDR

rf and digital signal processing for software-defined radio.

Springer-Verlag.2013 - Analog_RF and Mixed-Signal Circuit Systematic Design

simulation and software radio for communications 源码

Cognitive Radio Networks

一种用于软件无线电的接收机射频前端电路设计与实现-综合文档

数据库基础测验20241113.doc

微信小程序下拉选择组件

最新资源