A Miniature 35-110 GHz Modified Reflection-type BPSK Modulator Using 65-nm CMOS Technology

A miniature 35-110 GHz modified reflection-type BPSK modulator using a 65-nm CMOS process is presented in this paper. The core area of the modulator is only 150 × 370 µm2 due to a compact broadside coupler and a 1800 hybrid used in the BPSK modulator. The BPSK modulator demonstrates a modulation bandwidth of wider than 1 GHz, an error vector magnitude (EVM) of within 10%, a dc offset of better than 15 dB, and an adjacent channel power ratio (ACPR) of better than -35 dBc. The modulator is also evaluated by a bi-phase 4-level amplitude modulation scheme, and demonstrates good modulation quality with low dc offset. Therefore, it is suitable to apply to an IQ modulator design, and then the high-level modulation schemes can be performed, especially for millimeterwave (MMW) applications. To the best authors' knowledge, this work is the highest operation frequency among all the BPSK modulator using CMOS processes.