A high fidelity wide bandwidth (HFWB) buck converter with switching ripple cancellation for wireless communication application

This paper presents a ripple based fixed on time control scheme for a novel high efficiency linear transmitter. To support FCC power emission mask, this control scheme needs to have a wide bandwidth and to achieve high fidelity. Moreover, in order to improve linearity at far band due to extreme stringent emission mask regulation of the FCC, an auxiliary cancellation branch is adopted. The theoretical derivation in frequency domain is given to prove the system stability and high control bandwidth. Detailed large and small signals analyses of the modulator design are also presented in this paper. The simulation results are provided to verify the proposed design.