by admin | Jun 7, 2015 | sem3
Data Communications Data communications refers to the exchange of data between a source and a receiver. Data communication is said to be local if communicating devices are in the same building or a similarly restricted geographical area. The meanings of source and...
by admin | Jun 7, 2015 | sem3
Digital Communication System – Comparison DIGITAL COMMUNICATION SYSTEM – COMPARISON (ASK- FSK- PSK- QAM): S.No Parameter PSK DPSK QPSK QAM FSK ASK 1 Modulation of Phase Phase Phase Amplitude and Phase Frequency Amplitude 2 Equation of transmitted...
by admin | Jun 7, 2015 | sem3
Bandwidth Efficiency Spectral efficiency Spectral efficiency, spectrum efficiency or bandwidth efficiency refers to the information rate that can be transmitted over a given bandwidth in a specific communication system. It is a measure of how efficiently a limited...
by admin | Jun 7, 2015 | sem3
16 QAM 16-QUADRATURE AMPLITUDE MODULATION(16 QAM): Both amplitude and phase gets modulated. 4 bits encoded forming and producing 16 different outputa are possible. N = 4, M = 2N = 24 = 16 Therefore 16 output phases will be produced. 16 QAM transmitter: Each channel...
by admin | Jun 7, 2015 | sem3
8 QAM 8-QUADRATURE AMPLITUDE MODULATION(8-QAM): The amplitude gets changed in 8-QAM , and it is not a constant value. 3 bits encoded forming tribits and producing 8 different output phase. N = 3, M = 2N = 23 = 8 Therefore 8 output phases will be produced. 8-QAM...
by admin | Jun 7, 2015 | sem3
Quadrature Amplitude Modulation Quadrature amplitude modulation (QAM) is both an analog and a digital modulation scheme. It conveys two analog message signals, or two digital bit streams, by changing (modulating) the amplitudes of two carrier waves, using the...
