Patent ID: 7016606

Claim:
Optical WDM communications apparatus which line encodes a digital data stream so as to mitigate the effects of transmission errors comprising: an input device which provides a plurality of output words at an output thereof, each word containing an N number of bits, where N is a positive integer; a data memory comprised of N input address lines, each address line receiving one of said N bits, a plurality of addressable memory locations, and M parallel output data lines, each memory location containing a code word having an M number of bits, where a bit is either a one or a zero, and M is a positive integer greater than N, said code words being selected so as to minimize a variance in a set of code words of the number of one's in each code word, and where the code word contained in an addressed memory location is provided at said output data lines; and an output device connected to said memory output data lines and which provides a serial output data stream comprised of the output from said data memory.