Abstract
article presents an eight-channel 5-33-GHz transmit phased-array radio frequency integrated circuit (RFIC) for C-, X-, Ku-, and Ka-band SATCOM applications. The 4 x 2 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 C-, X-, and Ku-bands and +/- 30? scanning at Ka-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 16quadrature amplitude modulation (QAM) waveform are delivered to the phased array for performance evaluation, and < 4%- 4.8% error vector magnitude (EVM) is achieved in C-Ka-bands at P1dB (EIRP) operation. Application areas are C-/X-/Ku-/K a band ground terminals for satellite communications (SATCOMs).