To solve the problem that some results are skipped over or some errors occur during the process of searching some words and the recall and precision are low, the application of character based indexing technology to the search of Chinese Web documents is studied.

With the prior- knowledge that the seismic signal is composed of certain limited fre- quency band,the frequency-dominated fast MP algorithm creates dictionary index which regards frequency as main matching target, so that it can decrease the amount of dictionary index size and itera- tion computation,and promote the efficiency and computation speed of signal MP decomposition.