The primary requirement for maximum power transfer and minimum power loss is matched impedance in a transmission system. However, static design variations in system such as parasitics and dynamic variations such as changes in transmission frequency will result in reflections. A redesign or reconfiguration of complex systems is neither easy nor cost effective. A noble technique for compensating reflections in a communication system is presented here. The proposed methodology adapts the system to change without any modification to the system physical configuration. In this methodology compensation signals are added by I/O drivers with programmable phase delay and drive strength adjustments to cancel reflections. The concept application is demonstrated for a narrow bandwidth antenna system. An operating frequency off the antenna frequency results in a degraded received message eye. Using the proposed technique, without modifying the antenna, reflections were compensated and a significantly improved data eye was produced, as measured by the enhancement of critical performance parameters. The architecture of an expanded driver to implement the concept is outlined here. An algorithm and flow chart to dynamically identify and compensate for reflections are also presented.
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