An optical communication module comprises a plurality of monolithic semiconductor transmitter photonic integrated circuit (TxPIC) chips each having a plurality of optical signal channels approximating wavelengths on a standardized grid. Each of the channels comprises a laser source optically coupled to an electro-optic modulator. The outputs of the electro-optic modulators are coupled to inputs of an optical combiner integrated on each of the chips for combining the inputs to form a combined signal output from the chip. A second optical combiner combines the combined signal outputs from the TxPICs to form a combined optical signal group output. A booster optical amplifier is optically coupled to the second optical combiner to receive and amplify the combined optical signal group output from the second optical combiner.