Patent ID: 7609935

Claim:
An optical vector modulator comprising: a) an information generator that generates a plurality of N-bit streams at an output, each of the plurality of N-bit streams representing a desired modulation point in a signaling constellation; b) a memory look-up table having an N-bit address input that is electrically connected to the output of the information generator, the memory look-up table retrieving a first and a second stored values at a first and a second outputs that corresponds to the N-bit address input, each of the first and the second stored values representing a respective one of a first and a second modulation vectors of a desired modulation point in the signaling constellation; c) a first and a second digital-to-analog converters each having an input that is coupled to a respective one of the first and the second outputs of the memory look-up table, the first and the second digital-to-analog converters generating first and second analog signals, respectively, at an output that corresponds to respective ones of the first and second modulation vectors of the desired modulation points in the signaling constellation; and d) a dual-drive interferometric modulator having an optical input that is coupled to an output of an optical source, and a first and a second electrical modulation input that is coupled to a respective output of the first and second digital-to-analog converters, the modulator modulating the first and the second analog signals on the optical beam to obtain the desired modulation points in the signaling constellation.