The increasing demand for millimeter-wave (mmWave) frequencies with wider signal bandwidths, such as 5G NR, requires large investments on test equipment. This work presents a 5G mmWave up/down-converter with a 40 GHz LO, fabricated in custom PCBs with off-the-shelf components. The mmWave converter has broad IF and RF bandwidths of 1∼5 GHz and 21∼45 GHz, and the built-in LO generates 20∼29.5 GHz and 33.5∼40 GHz of output. To achieve high linearity of the converter simultaneously, the LO must produce low-phase-noise and be capable of high harmonics/spur rejection, and design techniques related to these features are demonstrated. Additionally, a reconfigurable IF amplifier for bi-directional conversion is included and demonstrates low gain variation to maintain the linearity of the wideband modulation signals. The final designed converter is tested with 5G OFDM 64-QAM 100 MHz 1-CC (4-CC) signals and shows RF/IF output power of -3/8 dBm with a linear range of 35 (30)/38 (33) dB at an EVM of 25 dB.

This paper presents a miniaturized transformer-based ultra-low-power (ULP) LC-VCO with embedded supply pushing reduction techniques for IoT applications in 65-nm CMOS process. To reduce the on-chip area, a compact transformer patterned ground shield (PGS) is implemented. The transistors with switchable capacitor banks and associated components are placed underneath the transformer, which further shrinking the on-chip area. To lower the power consumption of VCO, a gm-stacked LC-VCO using the transformer embedded with PGS is proposed. The transformer is designed to provide large inductance to obtain a robust start-up within limited power consumption. Avoiding implementing an off/on-chip Low-dropout regulator (LDO) which requires additional voltage headroom, a low-power supply pushing reduction feedback loop is integrated to mitigate the current variation and thus the oscillation amplitude and frequency can be stabilized. The proposed ULP TF-based LC-VCO achieves phase noise of -114.8dBc/Hz at 1MHz frequency offset and 16kHz flicker corner with a 103µW power consumption at 2.6GHz oscillation frequency, which corresponds to a -193dBc/Hz VCO figure-of-merit (FoM) and only occupies 0.12mm2 on-chip area. The supply pushing is reduced to 2MHz/V resulting in a -50dBc spur, while 5MHz sinusoidal ripples with 50mVPP are added on the DC supply.

An amplitude-redistribution technique – which improves phase-noise performance of millimeter (mm)-wave and quasi mm-wave cross-coupled VCOs by controlling the distribution of voltage swings on the oscillator nodes – is proposed. A 28-GHz VCO, fabricated in 0.13-µm CMOS technology, uses this technique and demonstrates low phase-noise performance of -112.9-dBc/Hz at 1-MHz offset and FOMT of -187.4-dBc/Hz, which is the highest FOMT so far reported in regard to CMOS VCOs operating above 25 GHz.

We describe a low-cost and extremely stable millimeter-wave transmission system that uses a double-side-band (DSB) millimeter-wave self-heterodyne transmission technique. This technique allows us to use a comparatively low-cost and unstable millimeter-wave oscillator regardless of the modulation format. Furthermore, a transmission band-pass-filter (BPF) is not needed in the millimeter-wave band. The system cost can therefore be substantially reduced. We have theoretically and experimentally evaluated the carrier-to-noise power ratio (CNR) performance that can be obtained when using this technique relative to that attainable through a conventional millimeter-wave self-heterodyne technique where a single-side-band signal is transmitted. Our results show that the DSB self-heterodyne transmission technique can improve CNR by more than 3 dB.