Chapter 6 OFDM/DMT for Wireline Communications. School of Info. Sci. & Eng. Shandong Univ. CONTENT. 6.1 Discrete MultiTone (DMT) and Wireline Channel Properties 6.2 Optical OFDM Transmission and Optical Channel Properties 6.3 Impulse-Noise Cancellation
School of Info. Sci. & Eng.
where N is the number of identical disturbers and the power of 0.6 is to halfways model the distribution of disturbers in cable.
where N is the number of identical disturbers, l is the length of the coupling length, and the power of 0.6 is to halfways model the distribution of disturbers in the cable
NEXT and FEXT
Measured NEXT of an 0.4-mm layered cable
Impulses resulting from welding and fluorescent tubes, measured at a telephone socket
Components of DMT transmission
Λ(n) is a diagonal matrix. P (n ) and Q (n) are unitary matrices.
at the receiver is multiplied by QH( n) to obtain the output r(n )：
x (n) is the product of P ( n) and t (n )
Spatial DFE structure resulting from QR decomposition
QR decomposition for downstream processing
Envelope of CM signal (green)
Second method for CM envelope detection
Investigated system: Dual polarization OFDM transmission, coherent detection.
Estimated relative noise power
Here h and c denote Planck’s constant and the speed of light, respectively. G is the amplifiers’ gain which shall equal the loss of one fiber span. The noise figure is given by FN
Iterative demapping and decoding, BICM-ID system configuration
Complete optical COFDM system
Simulations on systems performance; BER at BICM-ID output
EXIT functions of decoder and soft-demapper for different mappings at optical input power of -9 dBm