Abstract: The required fewest channels in the existing reconstruction algorithms of modulated wideband converter(MWC) was far from the theoretical limit, so we proposed minimum correlation(MinCor) algorithm and maximum-minimum correlation(Max-MinCor) algorithm. In MinCor, the noise subspace was regarded as the measurement matrix, and the support was calculated based on the minimum correlation between the measurement matrix and the sensing matrix. In Max-MinCor, we treat the noise subspace and signal subspace as the measurement matrix respectively, and the support was calculated based on the maximum correlation and the minimum correlation. The experimental results showed that both MinCor and Max-MinCor performed better in fewer channels, and the required number of channels is just one more than the theoretical limit without noise. MinCor was much less time-consuming, but its performance decreased if SNR<10dB, while Max-MinCor outperformed MinCor in the anti-noise capability, but did worse in reconstruction speed. The above two algorithms can be used to save hardware cost and reduce system volume.