EIE531:Radio Mobile Communication- Introduction(Chapters1-2)

Chapter 1: Introduction to Wireless Communication System

Chapter 2: Modern Wireless Communication System

Chapter3 : The Cellular Concept - System Design Fundamentals

 

3.1 Introduction

3.2 Frequency Reuse

3.3 Channel Assignment Strategies

3.5 Interference and System Capacity

3.6 Trunking(中继) and Grade of Service

3.7 Improving Coverage & Capacity in Cellular System

 

Chapter5: Mobile Radio Propagation: Small- Scale Fading and Multipath

(exclude section 5.2.1, 5.7.1.1, 5.7.3)

5.1 Small-Scale Multipath Propagation

5.2 Impulse Response Model of a Multipath Channel

5.4 Parameters(参数) of Mobile Multipath Channels

5.5 Types of Small- Scale Fading

5.6 Rayleigh(瑞利) and Ricean Distributions

5.7.2 Simulation of Clarke and Gans Fading Model

5.7.4 Two- ray Rayleih Fading Model

 

Chapter 4: Mobile Radio Propagation: Large-Scale Path Loss(损耗)

4.1 Introduction to Radio Wave Propagation

4.2 Free Space Propagation Model

4.4 The Three Basic Propagation Mechanisms(机制)

4.6 Ground Reflection(Two-Ray)Model

4.9.1 Log-distance Path Loss Model

4.9.2 Log-normal Shadowing

4.10.3 Okumura Model

4.10.4 Hata Model

4.10.5 PCS(个人通讯服务) Extension to Hata Model

4.11.1 Partition Losses(same floor)

4.11.2 Partition Losses between Floors

4.11.3 Log-distance Path Loss Model

4.11.5 Attenuation(衰减) Factor Model

4.12 Signal Penetration(渗透) into Building

Chapter 6: Modulation Techniques for Mobile Radio

6.4 Digital Modulation- an Overview

6.6 Puls Shaping Techniques

6.7 Geometric(几何) Representation of Modulation Signals

6.8 Linear Modultion Techniques

6.9 Constant Envelope(包络) Modulation

6.10 Combined Linear and Constant Envelope Modulation Techniques

6.11 Spread Spectrum Modulation Techniques

 

Chapter9

Multiple Access Techniques for Wireles Communications

9.1 Introduction

9.2 Frequency Division Multiple Access(FDMA)

9.3 Time Division Multiple Access(TDMA)

9.4 Spread Spectrum Multiple Access

9.5 Space Division Multiple Access(SDMA)

9.7.1 Capacity of Cellular CDMA

 

Chapter 1 Introduction

Mobile radio transmission systems may be classified assimplex, half-duplex or full-duplex.

In simplex systems, comunication is possible in only one direction.

Half-duplex radio systems allow two-way communication, but use the ame radio channel for both transmission and reception.

Full duplex systems, allow simultaneous radio tranmission and reception between a subscriber and a base station.

 

Frequency division duplexing(FDD) provides simultaneous radio transmission channels for the subscriber and the bas station, so that they bth may constantly transmit while simultaneously receiving signals from one aother.

 

The channel used to convey traffic to the mobile use from a base station is called theforward channel.

The channel used to carry traffic from the mobile user to a bas station is called thereverse channel. In the U.S.AMPS standard, the reverse channel has a frequency which is exactly 45 MHz lower than that f the forward channel.

 

Time division duplexing(TDD) uses the fact that it is possible to share a single radio channel in time, so that a portion of the time is used to transmit from the base station to the mobile, and the remaining time is use to transmit from themobie to the base station.

TDD is only possible with digital transmssion formats and digital modulaton, and is very sensitive to timing. It is for this reason that TDD has only recently been used, and only for indoor or small area wireless applications where the physical coverage distances are much smaller than the many kilometers used in conventional cellular telephone systems.

 

A bsic cellular system which consists of mobile stations, base stations and a mobile switching center(MSC).

The MSC coordinates the activities of al of the base stations and connects th entire cellular system to thePSTN(public switched telephone network).

 

When a cellular phone is turned on, but is not yet engaged in a call, it first scans the group of forward control channels to determine the one with the strongest signal, and then monitors that control channeluntil the ignal drops below a usable level. When a telephone call is placed to a mobile user, the MSC dispatches the request to all base stations in the celular system. Themobile identification number(MIN), which is the subscriber's telephone number, is then broadcast as a paging message over all of the forward control channels throughot the celular system.

 

Once a call is in progress, the MSC adjusts the transmitted power of the mobile and changes the channel of the mobile unit and base stations in order to maintain call quality as the subscriber(客户) moves in and out of range of each base station. This is called a handoff.(切换)

 

When a mobie originates a call, a call initiation request is sent on the reverse control channel. With this request the mobile unit transmits its telephone number(MIN), electronic serial number(ESN), and the telephone number of the called party. The mobile also transmits a station class mark(SCM) which indicates what the maximum transmitter power level is for the particular user. The cell base station receices this data and sends it to the MSC. The MSC validates the request, makes connection to the called party through the PSTN, and instructs the base station and mobile user to move to an unused forward and reverse voice channel pair to allow the conversation to begin.

 

All cellular systems provide a service called roaming.(漫游) This allows subscribers to operate in service areas other than one from which service is subscribed. When a mobile enters a city or geographic area that is different from its home service area, it is registered as a roamer in the new service area.

 

Chapter 2 Modern Wireless Communication Systems

Wireless networks have been increasingly used as a replacement for wires within homes, buildings, and office settings through the deployment of wireless local area networks(WLANs).

 

Unlike first generation cellular systms that relied exclusively on FDMA/FDD and analog FM, second generation(2G) standards use digital modulation formats and TDMA/FDD and CDMA/FDD multiple access techniques.

 

The most popular second generation standards include three TDMA standard and one CDMA standard: Global System Mobile(GSM), Interim Standard, Pacific Digital Cellular(PDC), the popular 2G CDMA standard Interim Standard 95 Code Division Multiple Access.