An 8-Channel 5–33-GHz Transmit Phased Array Beamforming IC With 10.8–14.7-dBm Psat for <i>C</i>-, <i>X</i>-, <i>Ku</i>-, and <i>Ka</i>-Band SATCOM
Oguz Kazan, Zhaoxin Hu, Linjie Li, Abdulrahman Alhamed, Gabriel M. Rebeiz
Abstract
This article presents an eight-channel 5–33-GHz transmit phased-array radio frequency integrated circuit (RFIC) for <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$C$ </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">$X$ </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">$Ku$ </tex-math></inline-formula> -, and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$Ka$ </tex-math></inline-formula> -band SATCOM applications. The <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$4\,\, {}\times {}2$ </tex-math></inline-formula> beamformer is implemented in a 90-nm SiGe HBT process. Each channel has a wideband two-stage power amplifier (PA), a phase shifter (PS), a variable gain amplifier (VGA), and a single-ended to differential (S2D) converter. The input radio frequency (RF) power is distributed to the eight channels using a two-stage lumped-element Wilkinson network and active dividers. The measured electronic gain is 24–27 dB at 5–33 GHz with 5-bit PS operation and >20 dB gain control. A peak OP1dB and OPsat of 10.8–14 dBm is achieved over the entire frequency range. The chip is then implemented in a wideband phased array using tapered-slot (Vivaldi) antennas. The 16-element phased array achieves ±60° scanning at <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$C$ </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">$X$ </tex-math></inline-formula> -, and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$Ku$ </tex-math></inline-formula> -bands and ±30° scanning at <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$Ka$ </tex-math></inline-formula> -band with a broadside effective isotropic radiated power (EIRP) of 16–38.5 dBm at 8–32 GHz. Quadrature phase shift keying (QPSK), 8-phase shift keying (PSK), and 16-quadrature amplitude modulation (QAM) waveform are delivered to the phased array for performance evaluation, and <4%–4.8% error vector magnitude (EVM) is achieved in <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$C - Ka$ </tex-math></inline-formula> -bands at P1dB (EIRP) operation. Application areas are <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$C-/X-/Ku-/Ka$ </tex-math></inline-formula> -band ground terminals for satellite communications (SATCOMs).