signals

Question 1

signals

Answer 1

variations of a physical quantity that encode information

Question 2

continuous

Answer 2

their level is known always and everywhere

Question 3

analog

Answer 3

their level is a infinite-precision real number

Question 4

period signal properties

Answer 4

volume
duration
period
frequency

Question 5

DC component or mean value

Question 6

speech

Answer 6

1D continuous analog time signal

Question 7

attenuation

Answer 7

gradual reduction of the amplitude of a signal

Question 8

image

Answer 8

2D continuous time signal

Question 9

digitisation

Answer 9

sampling + quantisation

Question 10

sampling

Answer 10

process of measuring a continuous signal at isolated, equally spaced moments in time

Question 11

quantisation

Answer 11

representing real numbers with a finite number of bits

Question 12

digital signal

Answer 12

non-continuous, changes in individual steps, takes discrete values

Question 13

ADC

Answer 13

device that preforms digitisation

Question 14

DAC

Answer 14

device that preforms reconstruction; needed for controlling the actuators

Question 15

reconstruction

Answer 15

reassembling an analog signal from the digital samples

Question 16

A/D resolution

Answer 16

refers to the number of bits used to represent the amplitude of an analog signal in a digital form after analog-to-digital conversion, determines the number of possible outputs
N=2^R, R-bits

Question 17

sampling frequency

Answer 17

number of samples per second

Question 18

vin

Answer 18

input analog voltage

Question 19

vref

Answer 19

analog reference voltage

Question 20

pixel

Answer 20

a discrete point in 2D space

Question 21

spatial reosolution

Answer 21

number of pixels per each direction

Question 22

colour reoslution

Answer 22

number of bits used to express the colour of a pixel

Question 23

binary image

Answer 23

one bit per pixel

Question 24

gray scale image

Answer 24

8 bits per pixel

Question 25

RGB

Answer 25

24 bits per pixel

Question 26

The Nyquist-Shannon sampling theorem

Answer 26

minimal sampling rate is 2fmax-the Nyquist sampling frequency

Question 27

for a good reconstruction it is recommended to use _________

Answer 27

10fmax

Question 28

aliasing

Answer 28

effect of undersampling, can lead to the misinterpretation or distortion of the signal

Question 29

alias frequencies

Answer 29

false frequencies resulted after reconstruction

Question 30

oversampling

Answer 30

bigger storage requirements