This paper presents a novel FET rectifier using one-port composite right-/left-handed transmission line as gate control circuit (GCC). The circuit is extremely compact and yet can control the gate impedance both at the fundamental frequency and at the 2nd harmonic frequency for self-synchronous operation of the rectifier. The prototype 2.45-GHz GaN FET rectifier rectified RF power of 34 dBm with RF-DC efficiency of 64% (without correcting for reflection). Compared with the rectifier using microstrip-based circuit, the proposed rectifier performed just as good, or even better, in terms of efficiency and bandwidth. The class-B FET rectifier of this work can potentially operate with higher efficiency by harmonic tuning at the drain circuit.