Modulation Representing digital signals as analog waveforms Baseband signals Signals whose frequency components are concentrated around zero Passband signals Signals whose frequency components are centered at some frequency fc away from zero Baseband signals can be converted to passband signals through modulation Multiplication by a sinusoid with frequency fc Eytan Modiano

Channel Coding When transmitting over a noisy channel, some of the bits are received with errors Example: Binary Symmetric Channel (BSc) Pe= probability oferror Q: How can these errors be removed? A: Coding: the addition of redundant bits that help us determine what was sent with greater accuracy

Source coding Source Encode Channel Alphabet alphabet Source symbols Letters of alphabet, ASClI symbols, English

Sampling Given a continuous time waveform, can we represent it using discrete samples? How often should we sample? Can we reproduce the original waveform?

Administrative matters Instructors: Eytan Modiano Meeting times: Tuesdays and Thursdays Text: Communications Systems engineering Proakis and salehi Grading 10% weekly Homework Assignments 30% each of 3 exams Final exam during final exam period

The mahalanobis distance in Character Recognition Authored by Dan Frey 31 July 98 This sheet explores the use of the Mahalanobis Distance in character It defines a letters a.b.c. and d It creates a population of distorted letters to train a classifier

Final Project Questions Let's take up to an hour to Review progress answer questions Referencing sources in the term project Direct quotes-- Place in quotes or indent and cite source in footnote or reference

Plan for the session Quiz on Constructing Orthogonal Arrays (10 minutes) Complete some advanced topics on oas Lecture on Computer Aided robust design Recitation on hw#5 Robust system design

Plan for the session Guest lecture by Eric Feron(1 hour) Quiz on Design of Dynamic Systems(15 minutes Review of reliability Improvement Case Study --Router Bit Life(35 minutes) 16.881

Learning objectives Introduce explore orthogonality Study the standard oas Practice computing dOF of an experiment Learn how to select a standard oa Introduce means to modify Oas Consider studying interactions in Oas Robust System Design