We propose a hexagonal 16QAM modulator based on compact microring resonators and validated through simulation and theoretical analysis. We have also analyzed the constellation points and calculated the mathematical equation for each of the constellation points. Equidistant symbols of hexagonal architecture have the advantage of a higher symbol detection margin compared to the classical 16QAM modulation format. A bit error rate (BER) of 10−3 is achieved at 16.5 dB optical signal to noise ratio (OSNR).