In this paper, the receivers and transmitters for multi-system transceivers are modeled by spectrum allocation to predict mutual interference. The mirror interference, resonance interference, intermediate frequency interference and the local oscillator interferes have been taken into consideration as interference parameters for prediction by computer codes. Potential interference from the systems can be identified in advance by spectrum allocation to reduce complexity of EMI test and meet the requirements of system EMC performance, realizing the electromagnetic compatibility and enhancing the reliability of equipment and systems.