A Ka-Band SATCOM Transceiver in 65-nm CMOS With High-Linearity TX and Dual-Channel Wide-Dynamic-Range RX for Terrestrial Terminal

In this article, a Ka-band satellite communication (SATCOM) transceiver is first presented using a standard CMOS technology. The proposed Ka-band SATCOM transceiver consists of a high-linearity transmitter (TX) and dual-channel receiver (RX); both TX and RX are based on direct-conversion architecture. By implementing the dual-channel RX, multiple multiplexing modes, including polarization multiplexing and frequency multiplexing, can be enabled depending on the application. The RX variable gain is distributed in both RF blocks and baseband blocks to achieve a wide input dynamic range. The LNA employs a dual-coupling transformer for a low-noise figure (NF) and wideband input matching; moreover, it enhances the amplifier unilateralization characteristic to mitigate the loading effect from switched attenuators. An adjacent channel interference (ACI) cancellation scheme is proposed to further enhance the RX linearity in the frequency multiplexing mode. In the TX, single-turn high-quality-factor transformer is employed to realize matching network and four-way power combining. A prototype of the SATCOM transceiver is fabricated in a standard 65-nm CMOS process. Under 1.05-V supply voltage, the TX achieves a ${P{_{SAT}}}$ of 20.5 dBm and an average output power of 12 dBm with 2% error vector magnitude (EVM) and a 37.6-dB ACPR. The dual-channel RX achieves an NF of 5.4 dB, an IIP3 of -30 dBm on the high-gain mode, the ACI cancellation is measured of 7.9 dB with a 100-MHz signal bandwidth.