Advantages/disadvantages/applications of various modulation schemes
1. DSB-SC
2. SSB-SC
3. VSB-SC
4.items 1~3 with
carrier
5. 8,16 level VSB-SC
6. FM
7.PM
8.PSK
9. ASK
10. M-ary PSK
Advantages
Lower power
consumption
The modulation system is
simple
Better management of
the frequency spectrum
Low power consumption
It is a compromise
between DSB and SSB.
Therefore it is easier to
generate than SSB-SC
Envelope detection is
possible
Increased immunity
to noise
Increased immunity
to noise
Power efficiency. System
is the simplest
Bandwidth efficiency
Require more bandwidth
11. QAM
An attractive alternative
to SSB-SC.
Sharp cutoff band-pass
filters are not required.
12. SHD AM/FM
RECEIVERS
Increased selectivity
against adjacent
channels
Power efficiency, Error
detection and correction
capability. Zero PSD at
f=0
Transmits more bits in a
symbol time.
13. LINE CODES
14. M-ary PAM
+
Disadvantages
Complex detection
Applications
Analog TV systems: to transmit color
information
The generation of exact SSB is
rather difficult.
Complex detection
Demodulation system is still
complex.
Its bandwidth is about 25%
greater than SSB-SC.
Low power efficiency
Two way radio
Frequency division multiplexing
Require a larger bandwidth
more complex receiving
hardware
Low bandwidth efficiency
Analog TV broadcast systems
Wireless broadcasting systems
ATSC digital television standard＋
Radio broadcasting; direct-satellite
broadcasting
data-communications systems
Low speed communication
Low power efficiency
Transmitted power is lower
V-32 Telephone data/fax modems
Satellite transmission of DTVB
programs.
Used in cable communication for
Compared with SSB, QAM is
more exacting in terms of the the transmission of DTV and
carrier frequency and phase or internet traffic between cable
modem and modem termination
the requirement for a
systems.
distortion-less transmission
medium
Radio broadcasting
Interference from signal
frequencies close to the
intermediate frequency
Transmit only one bit of
Optical communications
information over the interval
of Tb second
Require more power (M2)
less system complexity
High rate data links
M.S. Richer et al,” The ATSC digital television system”, proc. IEEE, vol.94, pp.37-43, Jan, 2006.
www.atsc.org
AM
ASK
ATSC
DSB
DTV
FM
PAM
PM
PSK
QAM
SC
SHD
SSB
VSB
Amplitude modulation
Amplitude shift keying
Advanced Television Systems Committee
Double sideband
Digital television
Frequency modulation
Pulse amplitude modulation
Phase modulation
Phase shift keying
Quadrature amplitude modulation
Suppressed carrier
Superheterodyne
Single sideband
Vestigial sideband