Wireless: End of Chapter 2

Went over audio stuff, sample size and rate.  Not sure what this has to do with chapter 2….

Digital Modulation Cont.

-Binary signals are digital data transmissions are typically sent in bursts of bits.  There are three types of binary signaling techniques that can be used:

Return-to-zero (RZ) calls for the signal to rise to represent 1 bit.  It must return to zero in its allotted time.

Non-return-to-zero (NRZ) the voltage signal remains positive, or high, for the entire length of the bit period.

Polar non-return-to-zero (polar NRZ) raises the signal to represent a 1 bit, but drops to a negative amount to represent a 0 bit.  Works well with light by using different colors.

A variation on a non-return-to-zero-level is a non-return-to-zero, invert-on-ones (NRZ-I).  A change in voltage level represents a 1 bit, whereas no change in voltage level indicates that the next bit is a 0. 

 The rising edge is on the left of the pulse, the falling edge is on the right.  The top is the level edge of the pulse.  

More After the Break

Wireless: Data Transmission

We are using Wireless# Guide to Wireless Communications by Jorge Olenwa and Mark Ciampa.  The pictures on here are screen clippings from either the book or the power points that my instructor is using. 

This first post is two classes combined. 

Chapter 2- Wireless Data Transmission

Notes and stuff after the break