SFCW Signal Generator Based on ATMega328 Microcontroller and Rl2R Ladder Networks

One of continuous waves signals frequently applied for through-wall radar (TWR) application is stepped-frequency continuous wave (SFCW). As a main part in SFCW-TWR system, the SFCW signal should be generated as precise as possible to rely the system works properly. In this paper, the SFCW signal generator is presented and designed based on ATMega328 microcontroller combined with Rl2R ladder networks. Here, ATMega328 microcontroller is applied to generate digital signals to be converted into analog signals by R/2R ladder networks. The use of ATMega328 microcontroller and R/2R ladder networks is expected to produce high quality SFCW signal as well as be low cost in order to be implementable for TWR with working frequency of 1600-2500 MHz. Prior hardware realization, the proposed SFCW signal generator was analyzed through simulation software in obtaining the SFCW signal satisfiable the requirement. The measured result shows that the signal produced by realized SFCW signal generator has a step signal form implementable for the desired application.