Interference suppression is one of the important functions for mobile communications and software radio. First, this paper shows a new type of interference suppression method by P-RCE (Probability-Restricted Coulomb Energy) which is applicable to mobile communications and software radio. P-RCE is one of the neural networks and mainly used in the field of pattern classification. Secondly, this paper presents several characteristics of this method. For example, it is found from our studies that good suppression effects can be performed even when the interference signals exist closely adjacent to the desired signal and/or total number of signals is more than that of the antenna elements. Next, this paper discusses two types of improvement of processing speed for new suppression method. One is the setting up the learning and non-learning intervals, and the other is the restriction of the number of prototype cells. According to the results, fairly good improvement is realized.