Abstract: Aiming at the specific protocol of RFID technology,a 915MHz CMOS transmitter front-end for OOK modulation is implemented in a 0.18μm CMOS process.The transmitter incorporates a class-E power amplifier (PA),a modulator,and a control logic unit.The direct-conversion architecture minimizes the required on-and-off-chip components and provides a low-cost and efficient solution.A novel structure is proposed to provide the modulation depth of 100% and 18%,respectively.The PA presents an output 1dB power of 17.6dBm while maintaining a maximum PAE of 35.4%.

Key words: CMOS, power amplifier, RFID, transmitter, modulation depth