Time division multiplexing (tdm) based optical ternary content addressable memory (tcam)

A optical ternary content addressable memory (TCAM) comprising:

• an input encoder configured to encode a search word on an optical search signal, wherein each bit position of the search word is represented by at least two time slots of a clock signal;
• a splitter optically coupled to an output of the input encoder configured to generate a plurality of copies of the optical search signal;
• a multi-word encoder configured to generate a plurality of TCAM word signals, each TCAM word signal encoding a TCAM stored word of a plurality of TCAM stored words and wherein each bit position of the TCAM stored word is represented by at least two time slots of the clock signal;
• an optical interleaver configured to route a copy of the optical search signal of the plurality of copies of the optical search signal and a TCAM word signal of the plurality of TCAM word signals to propagate in parallel as a plurality of pairs of inputted signals;
• a plurality of multipliers, each multiplier configured to receive a pair of inputted signals of the plurality of pairs of inputted signals and compare the respective copy of the plurality of copies of the optical search signal and the respective TCAM word signal;
• and
• a plurality of balanced photodetectors arrays, each balanced photodetector array optically coupled to an output of a respective multiplier of the plurality of multipliers,
• wherein each balanced photodetector array is configured to detect a mismatch between the respective copy of the plurality of copies of the optical search signal output from a first output of a respective multiplier and the respective TCAM word signal output from a second output of the respective multiplier by detecting light during at least one time slot of the clock signal.

A method comprising:

• receiving, by an input encoder, one or more search words;
• encoding, by the input encoder, each bit of each search word of the one or more search words in the time domain, wherein each bit of each search word is represented by at least two time slots of a clock signal;
• inputting, by the input encoder, each encoded bit of each search word to an optical search engine;
• comparing, by the optical search engine, each encoded bit of each search word to a corresponding bit of one or more TCAM stored words;
• determining a comparison result for each respective bit position;
• integrating, by a photodetector, a plurality of comparison results to determine if a search word of the one or more search words matches a TCAM stored word of the plurality of TCAM stored words;
• and
• if the integrated plurality of comparison results indicates a match between a search word and a TCAM stored word, determining a memory address associated with each respective TCAM stored word.