Design of a 3.5-GHz OOK CMOS transmitter with triangular pulse shaping

A low-power CMOS on-off keying (OOK) transmitter employing a triangular pulse shaping scheme is presented. The proposed pulse shaping circuit is based on a current-reused common-source stage, whose gain is controlled by modulating the gate-source voltage in a triangular form. The triangular control signal is generated by an opamp-based integrator. The proposed pulse shaping scheme can effectively support variable data rate. A 3.5-GHz OOK transmitter circuit adopting the proposed pulse shaping scheme is designed in a 0.13 μm CMOS process. It successfully modulates digital data from 100 kbps to 10 Mbps and delivers an output power of +2.5 dBm. The total current consumption is 4.17 mA from a 1.2 V supply voltage, of which only 0.57 mA is dissipated at the transmitter core excluding the output buffer.