Apparatus and method for forward error correction

Abstract

An apparatus and method for forward error correction (FEC) on a variable code length are provided. A forward error correction (FEC) apparatus for a transmission system includes a low pass filter (LPF) for passing only a low frequency component of a signal upon receiving an input signal having a predetermined line rate; an AC power meter for converting an energy value of an output signal of the LPF into a DC voltage value; a logarithm amplifier for receiving the DC voltage value from the AC power meter, for converting the DC voltage value being exponentially variable into a linear DC voltage value being logarithmically variable, and for outputting the linear DC voltage value to a digital signal processor (DSP); a digital signal processor (DSP) for determining the line rate of the input signal according to a magnitude of the DC voltage value and for outputting a control signal for generating a clock signal in response to the line rate to a clock generator; a clock generator for generating a clock signal in response to the control signal and for outputting the clock signal to a forward error correction (FEC) module; and, a forward error correction (FEC) module for receiving the clock signal from the clock generator and performing a FEC operation on the received signal.

Dependencies are inferred from the claim text.