A 27–39-GHz VSWR-Resilient Compact True Power and Gain Sensor With Built-In Sensing Error Compensation for Integrated Power Amplifiers

The output power of a transmitter (TX) array can degrade due to a variety of factors, such as device aging, thermal degradation, and load impedance mismatch of the power amplifier due to antenna mutual coupling. Power sensors are needed on phased arrays to detect if any output power degradation occurs. Of these events, we will mainly focus on antenna voltage standing wave ratio (VSWR)-related power degradation, as these events occur on a much shorter timescale compared with long-term effects such as device aging. VSWR-resilient power sensors are required to support these VSWR scenarios. They need to maintain high sensing accuracy and dynamic range (DR) even under unknown complex load impedances in a compact form factor. Therefore, this work presents a broadband VSWR-resilient compact power and gain sensor with integrated power amplifier (PA) that achieves a power sensing error (PSE) of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\leq$</tex-math> </inline-formula> <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\pm$</tex-math> </inline-formula> 1.5/3 dB over a VSWR of 2:1/3:1, respectively, from 27 to 39 GHz. Over the same 2:1/3:1 VSWR and frequency range, the DR is <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$&gt;$</tex-math> </inline-formula> 18.69/17.65 dB. The sensor consumes 24.8 mW of power and occupies only 0.044 mm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$^2$</tex-math> </inline-formula> , ensuring a low overhead implementation for array applications. The sensor is also PA design-agnostic and supports single-ended antennas.