A fully integrated 30GHz 16-QAM single-channel phased array transmitter with 5.9% EVM at 6dB back-off

A fully-integrated 30GHz single-channel phased array transmitter is demonstrated in a 0.25-μm SiGe:C BiCMOS process. The integration covers the baseband I/Q modulation up to the RF output, including a 40GHz PLL with an ultra-low phase noise. A phase shift resolution of 10° and an amplitude resolution of 5-bit are achieved with an LO phase-oversampling vector modulator. The CSP packaged transmitter delivers a saturation output power of 10∼13dBm over 27.6∼30.3GHz. The 40GHz PLL achieves a measured integrated phase noise of 1.5° RMS from 100Hz to 10MHz and has a reference spur <-70dBc. The transmitter chip achieves an EVM of 5.9% at 6dB back-off for 40-Mb/s 16-QAM modulation. The proposed transmitter is suitable for Ka-band VSAT and back-haul point-to-point applications.