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"Direct Sequence Spread Spectrum (DSSS)
DSSS multiplies the data bits by a very fast pseudo-random bit pattern (PN sequence) that "spreads" the data into a large coded stream that takes the full bandwidth of the channel. DSSS is the basis for CDMA cellphones and 802.11 Wi-Fi wireless transmission. For a technical example of DSSS technology, see cdma.
Frequency Hopping Spread Spectrum (FHSS)
FHSS continuously changes the center frequency of a conventional carrier several times per second according to a pseudo-random set of channels, while chirp spread spectrum changes the carrier frequency. Because a fixed frequency is not used, illegal monitoring of spread spectrum signals is extremely difficult, if not downright impossible depending on the particular method. FHSS is the transmission technology in Bluetooth. See integrated-business-systems-and-services-inc, wifiand bluetooth."
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Can you describe the fhss and dsss spread spectrum technologies?
"Direct Sequence Spread Spectrum (DSSS)DSSS multiplies the data bits by a very fast pseudo-random bit pattern (PN sequence) that "spreads" the data into a large coded stream that takes the full bandwidth of the channel. DSSS is the basis for CDMA cellphones and 802.11 Wi-Fi wireless transmission. For a technical example of DSSS technology, see cdma.Frequency Hopping Spread Spectrum (FHSS)FHSS continuously changes the center frequency of a conventional carrier several times per second according to a pseudo-random set of channels, while chirp spread spectrum changes the carrier frequency. Because a fixed frequency is not used, illegal monitoring of spread spectrum signals is extremely difficult, if not downright impossible depending on the particular method. FHSS is the transmission technology in Bluetooth. See integrated-business-systems-and-services-inc, wifiand bluetooth."From spread-spectrum
What are the Four primary technologies in which wireless lans uses in transmitting and receiving data?
a. Direct sequence spread spectrum (DSSS). b. Frequency hopping spread spectrum (FHSS). c. Infrared d. Orthogonal frequency division multiplexing(OFDM)
Working of frequency hopping spread spectrum?
exlanation of fhss block diadram
What is the signaling method used by Bluetooth?
FHSS(Frequency Hopping Spread Spectrum)
How can dsss benefits from multipath propagation?
It can't, Prof. Schiller is wrong In contrary DSSS is more vulnerable to multipathing than e.g. FHSS is since it could just ignore its own shadows after jumping.
What encoding or modulation technology does 802.11 use?
FHSS- Which has been dropped recently DSSS- which is still used by access points to advertise themselves
What is fhss?
FHSS continuously changes the center frequency of a conventional carrier several times per second according to a pseudo-random set of channels, while chirp spread spectrum changes the carrier frequency. Because a fixed frequency is not used, illegal monitoring of spread spectrum signals is extremely difficult, if not downright impossible depending on the particular method. FHSS is the transmission technology in Bluetooth. See http://www.answers.com/topic/802-11-technology, http://www.answers.com/topic/wi-fi-technology and http://www.answers.com/topic/bluetooth-technology. FHSS continuously changes the center frequency of a conventional carrier several times per second according to a pseudo-random set of channels, while chirp spread spectrum changes the carrier frequency. Because a fixed frequency is not used, illegal monitoring of spread spectrum signals is extremely difficult, if not downright impossible depending on the particular method. FHSS is the transmission technology in Bluetooth. See http://www.answers.com/topic/802-11-technology, http://www.answers.com/topic/wi-fi-technology and http://www.answers.com/topic/bluetooth-technology.
What is the difference between slow and fast FHSS?
The difference between slow and fast FHSS is the speed of the transmitting radio signals. Both have signals that are difficult to intercept.
What must the FHSS transmitting and receiving units know to communicate?
The hopping sequence.
When was the concept used by FHSS technology developed?
during World War II
Is 802.11g mobile wireless networking standard that uses FHSS RF signaling in the 2.4 GHz band?
No
Name the various types of multiplexing techniques?
Multiplexing techniques vary widely based on what is being multiplexed. Modern telecommunications use a very wide array of techniques including: TDM - examples: TDMA, T-carrier FDM - examples: DWDM Spatial - example: MIMO Code division - examples: CDMA Phase or polarization division - cable/satellite TV Statistcal - examples: packet mode (STS), FHSS etc etc. This is far from a complete list. I think the question needs to be more specific.
