This is the summary notes of the important terms and concepts in Chapter 2 of the book "Electronic Communications System" by Wayne Tomasi. The notes are properly synchronized and concise for much better understanding of the book. Make sure to familiarize this review notes to increase the chance of passing the ECE Board Exam.
CHAPTER 2 |
SIGNAL ANALYSIS AND MIXING |
Items |
Definitions |
Terms |
1 |
Electrical signals of which amplitude changes continuously with respect to time with no breaks or discontinuities. |
Analog Signals |
2 |
Electrical signals that are described as discrete; their amplitude maintains constant level for a prescribed period of time and then it changes to another level with respect to time with no breaks or discontinuities. |
Digital Signals |
3 |
Digital signal with only two levels possible. |
Binary Signal |
4 |
Digital signal with four levels possible. |
Quaternary Signal |
5 |
Is the mathematical analysis of the frequency, bandwidth, and voltage level of a signal? |
Signal Analysis |
6 |
A signal that repeats at a uniform rate. |
Periodic Wave |
7 |
A description of signal with respect to time. |
Time-domain Representation |
8 |
A time-domain instrument that shows signal waveforms. |
Oscilloscope |
9 |
The display on the cathode ray tube (CRT) that shows the shape and instantaneous magnitude of the signal with respect to time. |
Signal Waveform |
10 |
A description of signal with respect to its frequency. |
Frequency Domain Representation |
11 |
A frequency-domain instrument that shows amplitude-versus-frequency plot. |
Spectrum Analyzer |
12 |
Any repetitive wave that is comprised of more than one harmonically related sine or cosine wave. |
Nonsinusoidal / Complex Wave |
13 |
A mathematical series developed in 1826 by French physicist and mathematician Baron Jean Fourier used to analyze complex periodic wave. |
Fourier Series |
14 |
A mathematical tool that allows us to move back and forth between the time and frequency domains. It is used in signal analysis to represent the sinusoidal components of nonsinusoidal periodic waveforms. |
Fourier Series |
15 |
Waveform comprised of an average dc component and a series of harmonically related sine or cosine wave. |
Periodic Waveform |
16 |
Is the integral multiple of the fundamental frequency? |
Harmonic |
17 |
Is the first harmonic and is equal to the frequency (repetition rate) of the waveform. |
Fundamental Frequency |
18 |
If a periodic voltage waveform is symmetric about the vertical axis, it is said to have axes, or mirror, symmetry and is called an ________. |
even function |
19 |
If a periodic voltage waveform is symmetric about a line midway between the vertical axis and the negative horizontal axis and passing through the coordinate origin, it is said to have point, or skew, symmetry is called an ______. |
odd function |
20 |
If a periodic voltage waveform is such that the waveform for the first half cycle repeats itself except with the opposite sign for the second half cycle, it is said to have ________. |
half-wave symmetry |
21 |
The ________ of a waveform consists of all the frequencies contained in the waveform and their respective amplitudes plotted in the frequency domain. |
frequency spectrum |
22 |
The difference between the highest and lowest frequencies contained in the information. It is also the difference between the highest and lowest frequencies that the channel will allow to pass through it. |
Bandwidth of an information signal |
23 |
The ratio of the active time of the pulse to the period of the waveform. |
Duty Cycle |
24 |
The rate at which energy is dissipated, delivered, or used, and is a function of the square of the voltage or current |
Electrical Power |
25 |
A fourier transform where a time-domain signal is sampled at discrete times. |
Discrete Fourier Transform |
26 |
A new algorithm of fourier transform developed by Cooley and Tukey in 1965 where the computing time is proportional to n log 2n rather than n2. |
Fast Fourier Transform |
27 |
The process of combining two or more signals |
Mixing |
28 |
Occurs when two or more signals combine in a linear device, such as a passive network or a small-signal amplifier. Also called linear mixing. |
Linear Summing |
29 |
An amplifier where the output is simply the original input signal amplified by its gain. |
Linear Amplifier |
30 |
Occurs when two or more signals are combined in a nonlinear device such as a diode or large-signal amplifier. |
Nonlinear Mixing |
31 |
Undesired generation of multiples or harmonics of that frequency. |
Harmonic Distortion |
32 |
Desired generation of multiples or harmonics of that frequency. |
Frequency Multiplication |
33 |
The sum and difference of the two original frequencies. |
Cross Products |
34 |
The generation of any unwanted cross-product frequency when two or more frequencies are mixed in a nonlinear device. |
Intermodulation Distortion |
35 |
Desired cross products produced by mixing in a nonlinear device. |
Modulation |