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Can you describe the fhss and dsss spread spectrum technologies?
TomWanderman
"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
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What is full form of DSSS?
Direct-Sequencing 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)
Spread spectrum techniques fhss and dsss?
"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 is DSSS Methodology?
Direct Sequence Spread Spectrum It's one of the many protocols for transmitting data over a wire (or other medium)
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
How wide is each channel on an 802.11b-compliant DSSS system?
22 MHz Each channel is a contiguous band of frequencies 22 MHz wide
What other word does roald dahl use that means knowledgeable experts?
Roald Dahl uses the word "cognoscenti" to refer to knowledgeable experts in his writing.
How does the near and far effect influence TDMA systems?
The near-far problem is a condition in which a receiver captures a strong signal and thereby makes it impossible for the receiver to detect a weaker signal. There is a long-standing issue that the dynamic range of one or more stages of a receiver can limit that receiver's ability to detect a weak signal in the presence of strong signal. The near-far problem usually refers to a specific case of this in which ADC resolution limits the range of signals a receiver can detect in a direct sequence spread spectrum (DSSS) system such as CDMA. The receiver's AGCmust reduce its gain to prevent ADC saturation, which causes the weaker signal to fall into the noise of the ADC. This is different from a condition of one signal interfering with another because if the ADC had sufficient resolution, it would be possible to recover both signals. By contrast,TDMA systems are less vulnerable.
An 802.11b compliant wirelesss lan configuration using DSSS can have a maximum of how many non-overlapping co-located access points?
A maximum of three co-located direct sequence system are possible because channels 1, 6, and 11 are the only theoretically nonoverlapping channels.
A decision-support system is intended to produce information to support which type of decisions?
DSSs include knowledge-based systems. A properly designed DSS is an interactive software-based system intended to help decision makers compile useful information from a combination of raw data, documents, and personal knowledge, or business models to identify and solve problems and make decisions.
What data communication technology uses low power radio waves to transmit data?
There are many data communication technologies that use low power radio waves to transmit data, including:* CDMA (used in most cell phones)* FM (used in Family Radio Service walkie talkie)* frequency-hopping spread spectrum (FHSS) (used in Bluetooth)* direct-sequence spread spectrum (DSSS), used in IEEE 802.15.4, which in turn is used by ZigBee, MiWi, 6LoWPAN, etc.* amateur radio operators often try "QRP" operation (very low power) with many different communication technologies: CW (Morse code), AM audio, FM audio, PSK31 and Hellschreiber digital text chat, and etc.
