modeling lecture 1

8/7/2019 Modeling Lecture 1

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Arab American UniversityArab American University--JeninJeninArab American UniversityArab American University--JeninJenin

Faculty of Engineering and Information Technology

Telecommunications Engineering Department (TCE)Modelling and Simulation of Modelling and Simulation of

Communication SystemsCommunication Systems

Usin MATLAB and SIMULINKUsin MATLAB and SIMULINK

((1107141411071414))

Instructors: Dr. Hazem Khanfar

Eng. Bashar Mousa

Miss Ola Sbihat

Contacts:

PHONE: Ext. 613 E-MAIL: [email protected]

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Chapter 1: Introduction


Modeling and Simulation

Objective: To study and evaluate the behavior and performance

of systems

Computer-aided techniques developed to assist in

o e ng, na yz ng, an es gn ng o ommun ca on ys ems.

These techniques fall into two categories:

1. Formula-Based approach

2. Simulation-Based approach

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Modeling and Simulation of Communication Systems

The performance of comm. Systems can be evaluated using:

1. Formula-Based Calculations

(Analytical techniques, not tractable)

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2. Wave-from level simulation

(combine mathematical and empirical models)

3. Hardware prototyping and measurements

(costly and time consuming)



Chapter 1: IntroductionChapter 1: Introduction


Communication systemsPerformance Evaluation Techniques

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Formula-Based

Calculations

Wave-from level

simulationHardware prototyping

and measurements




Communication System can be:

Global communication network

Geosynchronous communication satellite

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Terrestrial microwave transmission system

Built-in modem in a personal computer




Simulation “hierarchy”

NetworksEvent driven simulations:

ns2, Opnet

Packets, messages, flows

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Links

DSP Circuits RF

Time driven simulations:SPW, Cossap, Simulink/Matlab

Algorithm simulations:

TI CodeComposer

Waveforms

Circuit simulations:

NC-{VHDL/Verilog}, Scirroco,

RF simulations:

PSpice, ADS,XFDTD





Hierarchical View

1. The top level is the comm. network, satellite, terrestrial, etc…

2. A link is made up of elements like modulators, encoders,

amplifiers. These might be analog or digital.3. The bottom layer deals with implementation of components such

as filters and equalizers, etc…

4. Circuit Simulations like SPICE or HDL

5. The focus of this course is on wave-form level simulation of

communication links (middle layer)

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Wave-from level Simulation of Communication Systems

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1. We are interested in evaluating BER performance of the system2. Analytical evaluation of BER is difficult because of nonlinearity

which leads non-Gaussian and non-additive noise

3. Some approximations can be made but not accurate.

4. Estimation of errors via simulation involves generation of input signals (input and two noise signals)

5. Process these inputs through models for filters and

amplifiers.





Historical Perspective

1. Waveform-level simulation started with the invention of analog

computers in the 1940’s (aircrafts and weapon systems)

2. In 1960’s, di ital simulation ori inated with block-oriented

languages such as MIDAS SCADS, …3. Applications of digital computers to circuit analysis with

programs such as ECAP, SPICE in the mid of 1960’s.

4. Software packages based on FFT and Z-transform began in early

1970’s such as SYSTID, CSMP, CHAMP, LINK.5. The BOSS software package was the first for simulation of

comm. systems (SPW, MATLAB/SIMULINK).

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modeling lecture 1

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