Power-line communication (PLC) systems use the existing power line as a communication channel between the nodes. Understanding the high-frequency behavior of the power line and loads at the PLC frequency band is essential for designing the PLC system to achieve the desired performance. Based on the impedance behavior of the channel, PLC transceivers can adaptively adjust their operating behaviors to operate more effectively and efficiently. Tracking the impedance variation would also enable smart-grid systems to implement channel health monitoring. In this research, an s-domain home power-line impedance model estimation method at the Federal Communications Commission band based on impedance signatures of the loads and cables as well as the load schedules is developed. The model contains the amplitude and phase characteristics of the impedance at the FCC band. The presented home appliance signature contains an s-domain impedance model and complex power consumption at the power-line frequency. Measurements have been made for nine different appliances and a standard cable with proper lengths is typically used in US homes in order to define their high-frequency impedance signatures. The performance of the status detection algorithm is tested for five different scenarios. Based on the experimental tests, we found that the method we proposed for detecting the working status of the appliances and the method for estimating PLC channel impedance works very accurately.