Electromagnetic radiation (radio waves, light) travels in free space. This radiation can be encoded to carry either analog information or digital information. An example of analog-encoded radiation is that emitted by an AM radio station. Examples of digitally-encoded radiation are a wireless home computer network and the next generation of television broadcasting.
Digital
Analog signals require higher fidelity than digital signals because digital are either on or off while analog are continuous. A small difference in an analog signal is not detectable while it requires a large difference to turn on into off (digital signal). Error correction is easier with digital signals.
With an analog signal, it shrinks with distance. So its gets harder to tell when it is "there". A digital signal shrinks with distance. So as long as it is detectable, it is "there". So as a wave gets attenuated and then not by, say, variations in weather, to respond to an analog signal gets more difficult. With a digital wave, if you can find it -- it's there.
Because the propagation velocity in the waveguide is less than in free space.
A digital signal. Specifically, a binary signal.
Radio "signals" are always analog, not digital. To send a digital signal, it must be converted to analog format, and then the received signal has to be re-converted to digital. So the Voyager and Viking space probes, for example, include a digital-to-analog converter attached to the radio transmitter, and the radio receivers here on Earth are routed through an analog-to-digital converter to make sense of them. You yourself may have such an "analog-to-digital" converter; they are called "modems", or "modulator/demodulator".
The basic elements in digital signal processing are an analog to digital converter, digital signal processor, and digital to analog converter. This process can take an analog input signal, convert it to digital for processing and offer an analog output.
Digital signals are "forced" to be either 1 or 0, whereas analog signals are not. This means that a signal of 0.8 will be pushed to 1 in a digital signal and will remain 0.8 in an analog signal, and 0.2 will be 0 digital and 0.2 analog. This means that in order to overwhelm a digital signal the noise must do much more work to be effective. digital signal have only two states analog have infinite states therefore more susceptible to noise
what are the characters of digital signal
Digital Signal Processing
digital signal
digital signal processor
An DAC convert digital signal to analog signal i.e Digital to Analog Converter. An ADC convert analog signal to digital signal i.e Analog to Digital Converter.
You need to make a distinction between analog and digital signals, and analog and digital data. Digital data can be sent on an analog signal by using a modem. Digital data sent on a digital signal is done over a wire using voltage pulses at two or more levels. Digital signals can't travel very far without amplifiers, but analog signals can cover huge distances, such as with satellite communications and even communications with deep space probes.
There are several devices called digital to analog converters for this purpose. 1s and 0s of the digital signal are used to represent the digital signal in analog form.
There are four possible combinations of encoding techniques -Digital data, digital signal -Digital data, analog signal -Analog data, digital signal -Analog data, analog signal
The signal sent to the TV must be a digital signal as well.