Patent ID: 8891684

Claim:
A nonlinear estimating apparatus, comprising: an information sequence acquiring unit, configured to acquire a symbol information sequence of a pulse signal inputted by a transmitting side, wherein the inputted pulse signal is a single-polarization signal; a perturbation quantity generating unit, configured to calculate a weighted sum of interaction items of pulses on one or more moments relative to a current moment to obtain an additive perturbation quantity and a multiplicative perturbation quantity produced on a transmission link with a certain length, wherein the additive perturbation quantity is a weighted sum of the interaction items of the pulses excluding a current polarization state at the current moment, and the multiplicative perturbation quantity is a weighted sum of the interaction items of the pulses including the current polarization state at the current moment; and a signal estimating unit, configured to estimate the signal received at a receiving side according to the symbol information sequence, the additive perturbation quantity and the multiplicative perturbation quantity, wherein the signal estimating unit uses the following formula: u ⁡ ( t = kT , z = L ) = ( A k + Δ k add ) ⁢ ⅇ j ⁢ ⁢ Δ k mul Δ k add = ∑ mn ≠ 0 ⁢ A m + k ⁢ A n + k ⁡ ( A m + n + k ) * ⁢ C ⁡ ( m , n , z = L ) Δ k mul = - j [ ∑ n ⁢ 2 ⁢  A n + k  2 ⁢ C ⁡ ( 0 , n , z = L ) -  A k  2 ⁢ C ⁡ ( 0 , 0 , z = L ) ] where, t=kT represents a pulse interval, z=L represents the length of the transmission link, A k represents the symbol information at the polarization state and where, Δ k add denotes the additive perturbation quantity, Δ k mul denotes the multiplicative perturbation quantity, C(m, n, z=L) denotes a weighted coefficient of each item, A m+k and A n+k denote respectively the symbol information of the pulses on the (m+k)th and the (n+k)th moments, and (A m+n+k )* denotes the conjugation of the symbol information of the pulses on the (m+n+k)th moment.