A 103 pJ/bit multi-channel reconfigurable GMSK/PSK/16-QAM transmitter with band-shaping

A 401~406MHz GMSK/PSK/16-QAM TX with band-shaping is realized in 65nm CMOS occupying area of 0.4mm
²
. Coupled DLL based phase interpolated synthesizer with injection-locked ring oscillator, we achieve frequency tuning and multi-phase output without any need of phase calibration. Through direct quadrature modulation at digital PA, the TX achieves less than 6% EVM for data rate up to 12.5Mb/s. The band-shaping maximizes spectral efficiency with ACPR of -33dB. Consuming 2.57mW, the TX achieves energy efficiency of 103pJ/bit.