Welcome to Signaling Basics Analog-Digital 0 miles Simplex 10 miles Half-Duplex 20 miles Duplex 25 miles Get Car Insurance in 15 minutes. Get an Oil Change in 5 minutes. Learn about Data Modulation Now! By: Kimberly Donald, Carlos Glover & Benjamin McCoy

Car drivers travel roadways to reach destinations Data travels (transmits) via signaling; signal strength is measured in volts/voltage

Amplitude Wavelength: Distance between corresponding wave points (ex. from one peak to the next) Bridge Arches=Frequency: the number of times a wave’s amplitude cycles; measured in Hertz (Hz) Shorter wavelength = higher frequency Longer wavelength = lower frequency Measures wave strength The Good: -Conveys more subtleties with less energy (ex. you can understand a human voice better than a digital one) The Bad: -Voltage is varied and imprecise; more susceptible to noise (ex. AM radio at night or during a storm may produce static)

0 = Negative, No Voltage Digital signals are made of precise voltages that are either positive or zero. Pulses in these signals are noted as either a 0 or a 1. 0s and 1s are binary digits, or bits. 1 = Existing, Positive Voltage The Good: -More reliable than analog signals -Not affected by noise as much The Bad: -Needs more pulses to transmit the same amount of information that analog signals can transmit in one wave

Phase = progress of a wave over time relative to a fixed point BA Phase difference is measured in degrees. Phase difference in the above picture would be measured by the degree difference between points A and B. B

Simplex Like cars travelling down a one way street, some transmissions can only be sent one way. Channels, distinct transportation paths for signals, are like the lanes of the road.

Half-Duplex A half-duplex allows transmissions one way at a time, which can be viewed as a construction zone closing off one lane of traffic, but letting cars pass both ways.

Full-Duplex I-10 Like an interstate a full- duplex allows transmissions to pass both ways at the same time. By bringing multiple channels together, a full duplex system can be made, just like bringing multiple lanes together to make a highway.

Data Modulation Data Modulation is a technology used to modify analog signals to make them suitable for carrying data over a communication path. Data Modulation can be used to make a signal conform to a specific pathway. Ex: FM radio station.

You have now traveled the road to signaling success! Today we learned about: Differences between analog and digital signals 3 directions of data transmission: simplex, half-duplex, and full-duplex The uses of data modulation