The method to improve performance of Linear Variable Filter （LVF） based spectrometers is proposed and validated. By this means， a compact 512×2 InGaAs spectral sensor with dynamic data fusion on both spatial and time domains is developed. In the spectral sensor， spectral channel is not a single pixel but a group of neighboring pixels with multi-frame measurements. The data from two pixel arrays are multiplexed to compensate possible sensor defects such as blind pixels. The wavelength calibration and experimental results show that the proposed methods can significantly reduce the wavelength spacing between spectral channels with the optical resolution limit of LVF.