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Orthogonal Frequency Division Multiplexing (OFDM) scheme has showed to be one of the more effective techniques for wireless communications systems. If the data symbol is not transmitted differentially, coherent detection is obliged and the channel estimation process is indispensable. In this proposal, different methods for channel interpolation are investigated for estimating the channel state information when a rectangular pilot pattern is used. A new and simple method named NPI (Nearest Padding Interpolation) for channel sample interpolation is proposed and its performance is analysed. The main concluded result show that it can be considered as a good alternative comparing with a variety of actual channel estimation methods in terms of the Mean Square Error (MSE), the Mean Phase Error (MPE) and the computational cost. Following introduction, description of the OFDM system and the applied pilot pattern are described in Section II. In Section III, different channel interpolation techniques such as optimal filtering using the minimum mean square error (MMSE), the zero padding interpolation (ZPI), biharmonic splines interpolation (BSI), and the IFFT based interpolation process (IFFT-I) are also studied. The analysis of the NPI and its performance compared with the rest of the filtering procedures is verified in Section IV. Finally, concluding remarks are summarized in Section V.