Applications and Advantages, Disadvantages of Spread Spectrum
Major Applications of
Direct Sequence Spread Spectrum (DS-SS)
1. Anti-jamming application that protects a jamming signal.
2. Signal transmission with low detectability — the signal is
intentionally delivered at a low power level. As a result, the signal is known
as an LPI signal since it has a low risk of being intercepted.
3. Supporting a large number of simultaneous signal
transmissions on the same channel, such as code division multiple access (CDMA)
or Spread Spectrum Multiple Access (SSMA) (SSMA).
Major Applications of Frequency Hopping Spread
Spectrum (FH-SS) System
1. For mobile communication, CDMA systems based on FH spread
spectrum transmissions are particularly appealing.
2. Wi-wireless Fi's local area networks (WLAN) standard.
3. Bluetooth's Wireless Personal Area Network (WPAN)
protocol.
Commercial
Applications of Spread Spectrum Techniques
Spread
spectrum signals are employed for the following purposes:
1) combating
or mitigating the negative effects of jamming (Intentional interference). It
can also be utilized for military purposes.
2) Allowing
numerous users to send messages over the same channel bandwidth at the same
time. Code Division Multiple Access (CDMA) or Spread Spectrum Multiple Access
is a method of digital communication in which each user (transmitter-receiver
pair) has a unique PN code for sending over a common channel bandwidth (SSMA).
This is a common approach in digital wireless communications.
3) Minimizing
inadvertent interference caused by other channel users.
4) self-interference
suppression owing to multipath propagation.
5) Hiding a
signal by transmitting it with low strength, making it impossible to detect in
the presence of background noise for an accidental listener. It's also known as
a signal with a low probability of intercept (LPI).
6)
Maintaining communication privacy while additional listeners are present.
7) In radar
and navigation, obtaining precise range (time delay) and range rate (velocity)
readings.
Advantages and Disadvantages of Direct Sequence
Spread Spectrum (DS-SS) System
The
advantages of Direct Sequence Spread Spectrum are:
1. It is the most
effective technology for combating deliberate interference (jamming).
2. It has a high level of anti-multipath signal
discrimination. As a result, multipath reception interference is successfully
reduced.
3. When compared to other systems, the DS-SS system
outperforms them in the presence of noise.
Disadvantages of Direct
Sequence Spread Spectrum are:
1. The output
rate of the PN code generator must be high. The length of such a sequence must
be sufficient to ensure that it is random.
2. The
acquisition time using the serial search method is too long. As a result, the
DS-SS system is slower.
Advantages
and Disadvantages of Frequency Hopping Spread Spectrum (FH-SS) System
Some advantages of
Frequency Hopping Spread
Spectrum are:
1. The PG
system has a larger processing gain than the DS-SS system.
2. The
distance between two points has little effect on synchronization.
3. The
acquisition time for the serial search system with FH-SS is shorter.
Some disadvantages of
Frequency Hopping Spread
Spectrum are:
1. The FH-SS
system's bandwidth is excessive (in GHz)
2. Digital
frequency synthesizers, which are complex and costly, are required.