Conventionally, linear precoding methods in a Cognitive Radio (CR) Multiple Input Multiple Output (MIMO) network mainly aim to limit or completely cancel the interference between Secondary Users (SUs) while achieving superior performance of the CR system. In contrast to the traditional?precoding method, this paper presents two novel precoding methods from the perspective of using interference, namely Cognitive Radio Partial Linear Precoding (CR-PLP) and Cognitive Radio Phase Alignment Linear Precoding (CR-PALP).?The theoretical analysis and simulation results show that these two methods both enhance the Signal to Interference and Noise Ratio (SINR) through constructive interference by taking advantage of the phase information of the constellation. Contrary to CR-PLP where the destructive interference is zeroed, CR-PALP rotates and converts it into constructive part. Then less Symbol Error Rate (SER) and enhanced information transmission rate are achieved with lower computational complexity.