Spatial gradient fluorinated alloy (GFA) with ZnF ₂ in the outmost region and CuZn alloy in the inner region that jointly contribute to a highly reversible Zn-metal anode.

This review paper provides a comprehensive examination of millimeter-wave radar technologies in automotive systems, reviewing their advancements through signal processing innovations. The evolution of radar systems, from conventional platforms to mmWave technologies, has significantly enhanced capabilities such as high-resolution imaging, real-time tracking, and multi-object detection. Signal processing advancements, including constant false alarm rate detection, multiple-input–multiple-output systems, and machine learning-based techniques, are explored for their roles in improving radar performance under dynamic and challenging environments. The integration of mmWave radar with complementary sensing technologies such as LiDAR and cameras facilitates robust environmental perception essential for advanced driver-assistance systems and autonomous vehicles. This review also calls attention to key challenges, including environmental interference, material penetration, and sensor fusion, while addressing innovative solutions such as adaptive signal processing and sensor integration. Emerging applications of joint communication–radar systems further presents the potential of mmWave radar in autonomous driving and vehicle-to-everything communications. By synthesizing recent developments and identifying future directions, this review stresses the critical role of mmWave radar in advancing vehicular safety, efficiency, and autonomy.

Sub-terahertz (sub-THz) frequencies (100–300 GHz) are gaining prominence in the development of next-generation wireless communication systems, promising ultra-high data rates and wide bandwidths essential for applications like 6G networks and beyond. Despite the immense potential of these frequencies, several design and implementation challenges remain, especially in transceiver architectures, high-order modulation, and beam-forming capabilities. In this paper, we survey recent advances in sub-THz transceiver design, with a particular focus on D-band frequencies. We explore the latest developments in circuit performance and architectures, including innovative transmitter and receiver designs that utilize direct-digital modulation (and demodulation) and phased-array systems. To ensure a comprehensive and up-to-date analysis, this work selects over 100 data points from top-tier conferences and journals, with most publications dating within the past five years, reflecting the state of the art in the field. Meanwhile, we discuss practical challenges, future directions, and opportunities to optimize sub-THz systems for high-speed, high-capacity wireless communication.

This article presents a D-band direct-digital modulation (DDM) transmitter with on-chip digital calibration blocks for future beyond-5G (B5G) wireless communication. The proposed DDM architecture mitigates the need for complex intermediate frequency (IF) generation and power-hungry digital-to-analog converters (DACs). The transmitter is implemented primarily in TSMC’s 16-nm p-FinFETs, which exhibit superior RF performance than n-type counterparts. The carrier generation block consists of an input buffer, an active balun, a frequency octupler with current shaping and common-mode (CM) suppression, and an output buffer. A switch-based variable gain amplifier (VGA), a digitally controlled artificial dielectric (DiCAD) transmission line, and current-absorbing devices on RF-DACs are implemented on each I/Q path to enable precise on-chip amplitude and phase calibration. Then, the calibrated complex vectors are sent to a three-stage power amplifier (PA) with capacitive neutralization to drive a 50- $\boldsymbol {\Omega }$ load. The transmitter has a 3-dB bandwidth of 17 GHz, ranging from 129 to 146 GHz, a $P\mathbf {_{\text {sat}}}$ of 12.2 dBm, a total dc power consumption of 235 mW, and a total chip area of $\mathbf {1 ~\text {mm}^{2}}$ . It supports modulation schemes, including QPSK, 16-QAM, and 64-QAM with symbol rates of 2, 4, 6, and 8 GS/s. A maximum data rate of 48 Gb/s (4.9-pJ/bit efficiency) is achieved with 64-QAM and an EVM of −23.8 dB, demonstrating the potential of FinFET-based D-band systems-on-chip (SoCs) for B5G communication.