Study of using complementary S matrix to enhance SNR in Hadamard spectrometer

This paper proposes a complementary S matrix code modulation scheme for digital-micro-mirror (DMD) spectrometer. Theoretical analysis supports that the complementary S matrix has good properties, which can increase signal-to-noise ratio (SNR) approximately 2 times compared with S matrix. Through signal modeling of the spectrum, we construct the complementary S matrix to improve the noise in digital. It is proved that the complementary S matrix could reduce the noise of stray light and dark current in implementing process. When this scheme is applied in DMD spectrometer for experimental verification, the results are as follows: the 63 order complementary S matrix coding scheme improvement is 1.69 times compared with same-order S-matrix coding scheme in SNR, which is close to the theoretical analysis.