| Abstrakt: |
This paper has proposed a 57GHz 64GHz 12Gbps PAM4 RF modulator with LO leakage cancellation, which is implemented in 65nm CMOS technology. To generate 4-level output signal, the proposed PAM4 modulator has utilized three unit OOK modulators, which is consisted of a LO leakage canceller and a general OOK modulator. Since the DC current source of each unit OOK modulator can be varied differently by digital code, it performs a pre-distortion function by adjusting the degree of signal amplification. It also can provide a constant output impedance, regardless of the output signal levels. To further amplify the PAM4 output signal, a two-stage driver amplifier has used. The simulated results of the overall PAM4 modulator and driver amplifier show a 3dB bandwidth of 20GHz (57GHz to 64GHz), an output P1dB of +3.3dBm, and an output return loss of more than 10dB. It consumes 10mA/30mA from a 1.2V/0.8V supply voltage respectively. [ABSTRACT FROM AUTHOR] |
