In the state-of-the-art wireless communication system, the energy consumed by RF front-end is always more than that of digital sections. As a result, we must minimize it to design energy-quality wireless systems. In this paper, we update our former work on RF front-end energy model and minimize the energy consumption in RF circuit by adjusting the base-band parameters, such as modulation level, data rate and signal peak-to-average ratio (PAR) etc. We compared the power consumption of different modulation schemes of MQAM and MPSK first, and compare the energy efficiency in wireless system. In the mean while, we consider the impacts of circuit thermal noise, 1/f noise, the harmonic distortion and the channel flat fading, on the communication quality. At last, we propose the steps of the system design by choose the most energy efficient system parameters under certain bit error rate (BER) requirement.