In spread spectrum communications such as UWB systems, synchronization is needed in order to demodulate the information data from the received signal. There are two stages of synchronization, which are the acquisition and the tracking. The aim of acquisition is to find the phase of the sequence at the initial stage of signal reception. Acquisition is one of the key issues in spread spectrum communications. Many kinds of acquisition schemes have been proposed. All papers about acquisition employ the rectangle shape as the pulse shape or assume that the step size is equal to the pulse width. Those conditions are very different from actual environment conditions. This paper shows how the performance of acquisition scheme is changed depending on step size, threshold, etc on AWGN channel through the computer simulation and numerical analysis when Gaussian wave pulse is employed.