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A D-Band Vector Modulator for Imaging Applications in 130nm SiGe
  • Jonathan Wittemeier ,
  • Nils Pohl
Jonathan Wittemeier
Ruhr University Bochum

Corresponding Author:[email protected]

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Nils Pohl
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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.