802.11ah Transmitter with −55dBr at $\pm 3\text{MHz}$ and −58dBr at $\pm 20\text{MHz}$ ACLR and 60dB 2nd-order Harmonic Rejection for 470MHz ~ 790MHz TV White Space Band Devices

A novel 802.11ah transmitter for TV white space (TVWS) band devices is presented. To realize the transmitter meeting the stringent FCC and ETSI TVWS device emission limits for the adjacent channels and FCC restricted bands, a low noise and high linear class- AB voltage- to-current converter (V2I) as the mixer driver and a 2nd -order harmonic notch filter with the frequency tracking capability on the power amplifier (PA) load are newly proposed. The designed transmitter is implemented in a 40nm CMOS process as a part of the TVWS band 802.11ah connectivity System-on-Chip (SoC), and the measured results with the 802.11ah CBW4 signal show −55dBr and −58dBr Adjacent Channel Leakage Ratio (ACLR) at
$\pm 3\mathbf{MHz}$
and
$\pm 20\mathbf{MHz}$
frequency offset, respectively, and 60dB 2nd harmonic rejection for 470MHz ~ 790MHz TVWS bands. This transmitter is the first SoC level transmitter meeting the FCC and ETSI ACLR requirements.