Figure 6.7:
Distorsion
Bandbredd = övre gränsfrekvens – undre
gränsfrekvens
Figure 3.6 Sine wave examples (continued)
Figure 3.9 Three harmonics
Figure 3.10 Adding first three harmonics
Figure 3.11 Frequency spectrum comparison
Point-to-point communication
Mikrofon Högtalare
Source coding Source decodingDigitalizatingcompression
0110 0110
Error management Error control.
0100010
Bitfel
0110010
Flow control Flow control
Modulation Demodulation
0110010NACKACK
Layer6
Layer2
Layer1
Layer7
Quantization noice
Digital modulation methods
Binär signal
ASK = Amplitude Shift Keying (AM)
FSK = Frequency Shift Keying (FM)
PSK = Phase Shift Keying (PSK)
Spread spectrum
DS-CDMA = Direct Sequence Code DivisionMultiple Access
Chip sequencies
Figure 13.15 Encoding rules
Figure 13.16 CDMA multiplexer
Figure 13.17 CDMA demultiplexer