What is FHSS and DSSS spread spectrum?

A collective class of signaling techniques are employed before transmitting a signal to provide a secure communication, known as the Spread Spectrum Modulation. The main advantage of spread spectrum communication technique is to prevent “interference” whether it is intentional or unintentional.

What is spread spectrum explain FHSS?

Frequency-hopping spread spectrum (FHSS) is a method of transmitting radio signals by rapidly changing the carrier frequency among many distinct frequencies occupying a large spectral band. FHSS is used to avoid interference, to prevent eavesdropping, and to enable code-division multiple access (CDMA) communications.

Why is CDMA spread spectrum?

These systems were designed using spread spectrum because of its security and resistance to jamming. Asynchronous CDMA has some level of privacy built in because the signal is spread using a pseudo-random code; this code makes the spread-spectrum signals appear random or have noise-like properties.

What is spread spectrum?

Spread Spectrum refers to a system originally developed for military applications, to provide secure communications by spreading the signal over a large frequency band. These narrowband signals are easily jammed by any other signal in the same band.

Which is better FHSS or DSSS?

DSSS, in contrast, spreads the signal across a wider bandwidth than FHSS, creating a lower power density across the spectrum. Because FHSS allows more channels in the same frequency band, FHSS systems can support a greater aggregate bandwidth for coverage.

What is the difference between FHSS and DSSS?

DSSS is a very sensitive technology while FHSS is a robust one. FHSS spreads the signal by hopping with a bandwidth of 83 MHz while in using DSSS spreads the signal by adding redundant with a bandwidth of 22 MHz. DSSS prone to errors but at a low level as compared to FHSS system. FHSS produces strong bursty errors.

What are the applications of spread spectrum?

Spread spectrum communication systems are widely used today in a variety of applications for different purposes such as access of same radio spectrum by multiple users (multiple access), anti-jamming capability (so that signal transmission can not be interrupted or blocked by spurious transmission from enemy).

What is the advantage of CDMA?

One of the main advantages of CDMA is that dropouts occur only when the phone is at least twice as far from the base station. Thus it is used in the rural areas where GSM cannot cover. Another advantage is its capacity; it has a very high spectral capacity that it can accommodate more users per MHz of bandwidth.

Is DSSS and CDMA same?

Direct sequence spread spectrum (DSSS) transmission employs a chipping code to “spread” the transmission over a wider frequency band than it would normally occupy. DSSS is a form of CDMA (see Chapter 4). But instead of a pseudorandom binary sequence (PRBS), an 11-bit Barker code is used as the spreading sequence.

Where is spread spectrum used?

Spread-spectrum clock generation (SSCG) is used in some synchronous digital systems, especially those containing microprocessors, to reduce the spectral density of the electromagnetic interference (EMI) that these systems generate.

What is FHSS What are the advantages of DSSS over FHSS?

IEEE 802.11 Standard Overview IEEE 802.11 FHSS provides the following advantages (in comparison to DSSS): Greater tolerance of signal interference because of operation over wider (83.5MHz) bandwidth. Capability to operate up to 10 collocated access points without significant interference.

What is the difference between CDMA and DSSS?

CDMA is dealt with in a more detail manner and is presented with a mathematical explanation. Chapter five presents a MATLAB simulation of direct sequence spread spectrum (DSSS), Frequency hopping spread spectrum (FHSS) and Code division multiple access (CDMA).

What is the concept of spread spectrum and DSSS?

Explain FHSS and DSSS in detail. What is the concept of Spread Spectrum. Explain FHSS and DSSS in detail. It is an important encoding method for wireless communications to spread data over wide bandwidth and makes jamming and interception harder Each bit is represented by multiple bits in transmitted signal Chipping code

What is the purpose of direct sequence spread spectrum?

DSSS, direct sequence spread spectrum is a form of spread spectrum transmission which uses spreading codes to spread the signal out over a wider bandwidth then would normally be required.

Why is the DSSS power spread over a wideband?

Jamming resistance: The Dsss spectrum power is distributed over a wideband. Hence, these signals are difficult to jam. The PSD of jamming signal decrease by a factor N because of the spectrum spreading. Hiding of signal: The DSSS signal spectrum is spread over a wideband .

What is FHSS and DSSS spread spectrum? A collective class of signaling techniques are employed before transmitting a signal to provide a secure communication, known as the Spread Spectrum Modulation. The main advantage of spread spectrum communication technique is to prevent “interference” whether it is intentional or unintentional. What is spread spectrum explain FHSS? Frequency-hopping…