Wireless health monitoring for CFRP structures reduces the cost and time of inspection and it can be useful for continuous monitoring. In the previous study, we presented a wireless sensor for detection of internal delamination in a CFRP laminate. The method utilizes a simple electric resistance change in CFRP, thus it monitors delamination at only one location. For monitoring of large-scale structures, however, many sensors have to be distributed to cover the structure. Major problem for using many sensors is the time synchronization among sensors. To overcome the problem and enable to monitor strain/damage at multiple locations with time synchronization, we develop wireless strain/damage sensor which simply consists of a bridge circuit, voltage controlled oscillator and amplifiers. Since the sensor does not need procedures of AD conversion or memory storing, the time delay does not take place. Each sensor has original basic frequency which changes due to the electric resistance, and the frequencies from multiple sensors are transmitted to a receiver. Using short-time maximum entropy method, received wave is converted to multiple electric resistance data at one time. The proposed method is applied to CFRP laminates and oscillating frequencies are measured in real-time. As the result, the system successfully measures the applied strain and detects fiber breakage at multiple locations in CFRP laminate with time synchronization.