M
asked on
What does symbol mean when referring to Phase-Shift Keying?
What does symbol mean in the following sentence: More advanced versions of PSK can encode multiple bits per symbol.
From "CWNA Certified Wireless Network Administrator Official Deluxe Study Guide: Exam CWNA-106."
PSK in this context means: Phase-Shift Keying
From "CWNA Certified Wireless Network Administrator Official Deluxe Study Guide: Exam CWNA-106."
PSK in this context means: Phase-Shift Keying
ASKER CERTIFIED SOLUTION
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Hye=) M,
(PSK)-phase shift keying is a sort of modulation technique for signal of digital Tellecommunication transmission system whicha include recieving and transmitting party as contarctrary.FSK,CSK are more advance thechniques arbitrarly.symbol bit rate is a cahracteristic feature of received signal by a device or machine that hasfor an has an effect BER performance of overall system.
(PSK)-phase shift keying is a sort of modulation technique for signal of digital Tellecommunication transmission system whicha include recieving and transmitting party as contarctrary.FSK,CSK are more advance thechniques arbitrarly.symbol bit rate is a cahracteristic feature of received signal by a device or machine that hasfor an has an effect BER performance of overall system.
Just to be clear: the symbol is NOT the smallest unit of information - at least not necessarily. A "bit" is the smallest unit of information and a symbol may be multibit and carry N^2 units of information where N is the number of bits per symbol. That works at the signal level to describe. Then, useful information may depend on SNR, BER, etc.
So it became more or less equivalent to bits / second. Later specifications went to bits per second as unit of speed.
Regular Phone lines were up to 1200 Baud (Full Duplex) or 2400 Baud (Half Duplex). Where speeds increased when meassured in bps.
Higher speeds were done using more bits/symbol and beyond 19K2 using compression of data).
DSL is a different beast where ATM is involved. (More frequncy bands, using similar techniques).
Note: bps = bits per second, Bps is Bytes per second, where Bytes are groups of 8 bits.
For speed measurements bps is the standard to be used.
(Some people say 10MBps (10 Mega Byte per second) and measure this using FTP transfer f.e. This is a problem: then 10MB is a netto amount of data, all extra info needed for the network is overhead which is also measured.... You would need 100Mbps to get to that capacity and rather large packets to avoid overhead. each TCP packet adds 20 bytes , IPv4 needs 20 bytes, Ethernet has an overhead of 16 bytes of overhead / frame.. of max. 1498 bytes. [ and has a minimal idle gap between frames ] roughly 4% overhead + gap...
So for Ethernet the bast case scenario roughly is 10MBps (measured) == 80Mbps + overhead = 100Mbps.
Overhead = 20Mbps of which 4Mbps + gap. so About 16Mbps is overhead lost gaps (and waiting on responses during start/stop of transmisiion).
Also Don't say: mbps (Unless you Do mean milli bits per second 1/1000 of a bit per second, ie. 1000 seconds to send one bit)) There is a Billion times difference between m & M.