This paper presents a lightweight power consumption model and its generation method for quickly and accurately analyzing the power consumption of wireless communication devices. Many power analysis methods for VLSI circuits have been proposed before. However, most of them are based on hardware simulation which is very slow and power consuming. Therefore, they cannot be applied for analyzing the run-time power consumption of battery powered devices where the low power consumption is the most important criterion. In our method, the power analysis can be done with a small overhead. Experimental results with an N810 terminal developed by Nokia, and an Android Dev Phone by HTC demonstrate that the error of our power analysis method is on an average 4.33% compared to the measured power results. Once the power consumption model has been developed for a target device, the power consumption of application programs running on the device can be analyzed in real-time with a small power overhead.