A W-Band +7dBm Output Power Direct Digital RF Transmitter Using Manchester-Encoded 1-bit BPDSM and Frequency Tripler

This paper first demonstrates a W-band high-output-power direct digital RF transmitter using a Manchester (MAN)-encoded 1-bit band-pass delta-sigma modulation (BPDSM) and a frequency tripler. This direct digital RF transmitter eliminates the need for analog up-converters (a local oscillator (LO) and a mixer), and is composed solely of commercial off-the-shelf (COTS) components. The 5th and 6th image signals (30GHz and 33GHz) of a 22Gbps MAN-encoded 1-bit BPDSM signal (fundamental frequency of 1.5GHz) are applied to an active tripler. The 17th image component (93GHz) is then extracted from the tripler's output as the transmission signal. The measured results show the successful generation of a 93 GHz signal using the direct digital RF transmitter without up-converters. The measured 5Msps-QPSK signal at 93GHz achieves the output power of +7.0dBm, ACLR of -25.2dBc, and EVM of 6.4%. Furthermore, the measured 5Msps-16QAM signal achieves the output power of +5.1dBm, ACLR of -23.3dBc, and EVM of 12.8%.