| Each letter in the word is represented by
| |
| | noise is purely random. This theorem may
|
| different signal amplitude using thirty
| |
| | be used as a very good approximation for
|
| two scale order. If we do so information
| |
| | the ultimate channel capacity of most of
|
| flow speed gets greatly increased as per
| |
| | the transmission channels in spite of the
|
| Hartley law. Since now each letter is
| |
| | fact that the noise present in most
|
| represented by one symbol instead of
| |
| | channels is never perfectly random. It is
|
| five. But in such a case noise will cause
| |
| | found that the limiting channel speed for
|
| numerous error making the system useless
| |
| | a typical telephone channel is about
|
| extremely large transmitting power is
| |
| | thirty three kilo bits per second. How
|
| used. This fact may be established on
| |
| | ever speeds used in practice over such
|
| comparing the power requirements for the
| |
| | channels do not normally exceed eleven
|
| binary coding system and any N-level
| |
| | kilo bits per second. Doubling the speed
|
| system under the same noise conditions.
| |
| | the bandwidth of a noise limited channel
|
| For a given transmission and coding
| |
| | will double its capacity would amount to
|
| system there results are threshold noise
| |
| | misinterpretation. Actually the capacity
|
| levels below which practically no errors
| |
| | gets increased by only eighty percent
|
| occur due to noise. Using binary code
| |
| | depending upon signal to noise ratio.
|
| noise has to compete with the full power
| |
| | Thus we see that there exists possibility
|
| of the transmitter to cause any serious
| |
| | of trading bandwidth for signal to noise
|
| error. It is found that in a practical
| |
| | ratio. It may also be noted that a low
|
| channel, signal to noise ratio of thirty
| |
| | channel capacity does not mean that the
|
| decibel ensures almost error free
| |
| | desired amount of information can not be
|
| reception. This thirty decibel ratio
| |
| | seen over a given channel. It simply
|
| implies that noise power be one by
| |
| | means sending this amount of information
|
| thousand of signal power or root mean
| |
| | takes longer time. Lastly it may be seen
|
| square noise voltage be one by thirty one
| |
| | that the Shannon-Hartley theorem
|
| of root mean square signal voltage.
| |
| | represents a fundamental limitation. Any
|
| The transmitted power is required to rise
| |
| | attempt to exceed the Shannon limit would
|
| tremendously if a desired high signal to
| |
| | result in unacceptable error rate. In
|
| noise power ratio is to be maintained on
| |
| | good quality transmission system maximum
|
| increasing signaling speed that is on
| |
| | acceptable error ratio is one in 1000000.
|
| increasing the number of coding levels.
| |
| | All the messages sent though the noise
|
| Shannon-Hartley theorem gives the maximum
| |
| | limited channel are unpredictable or
|
| signaling speed in a channel in which the
| |
| | random.
|
