Currently, commercial radar systems are mainly found in the E-band. However, higher frequencies offer significant advantages in terms of absolute bandwidth and system design. The use of on-chip antennas and FR4 PCB materials is enabled by frequencies above ≈100 GHz. This work presents two wideband and fully integrated signal sources for radar applications at 90 and 180 GHz. By using the novel 90nm SiGe BiCMOS B12HFC technology, the signal sources provide up to 6.43dBm and 3.8dBm output power and dc-to-RF efficiencies of 4.59% and 0.98%, respectively. Furthermore, the two signal sources achieve a tuning range of 24.1 GHz (26.6%) and 51.7 GHz (28.8%). The 90 GHz signal source is based on a fundamental voltage-controlled oscillator and a static by-16 frequency divider, which operates up to 120 GHz. The divided LO signal allows the use of commercial PLL components to enable different modulation schemes. The 180 GHz signal source uses the same building blocks but is extended by a power amplifier and a bootstrapped Gilbert-Cell based frequency doubler, which has a differential output.

Radar systems are gaining in popularity and spreading into more and more applications due to their robust measurement method. While single-chip solutions have been published in the last decade in the upper millimetre-wave range, solutions are still very limited in the lower THz range. In this paper, a 0.48THz FMCW-radar transceiver MMIC in a 130nm silicon-germanium (SiGe) technology is presented. The MMIC consists of one Tx and Rx channel, respectively. The components for frequency synthesis and on-chip patch antennas are fully integrated into the MMIC. The achievable tuning range of the MMIC is 0.448 − 0.491 THz with a peak on-chip output power of about -9.4 dBm. The MMIC was designed and manufactured with the IHP SG13G3 technology.

Radar-based 3D sensing applications are increasingly used today to locate objects. Besides automotive and military applications, the number of civil and security applications also expands. However, numerous antennas are required for detailed 3D images, which impacts the sensor size. Higher center frequencies can reduce the antenna spacing and, thus, the array size. Alternatively, the array size can be kept the same to increase the number of antennas and, thus, the spatial resolution. 3D detection with an FMCW radar is only possible when the antenna beam is spatially steered (e.g., phased-array radar), or digital beam-forming is performed (multiple-input multiple-output (MIMO) radar). This paper presents a 125 GHz vector modulator (VM) that can either shift the phase for phased-array operation or turn individual transmit channels on or off for time-division MIMO. The VM was fabricated using the B11HFC technology from Infineon Technologies AG and consists of 4 compactly interconnected power amplifiers (PAs): Two are fed with an in-phase (I) signal, and two are fed with a quadrature (Q) signal. Within the pairs, the PAs are each cross-connected to a common inductive load such that the I and Q signals can be inverted. Thus, output phases between 0° and 360° are possible.