0.25- $\mu \text{m}$ BiCMOS System-on-Chip for K-/Ka-Band Satellite Communication Transmit–Receive Active Phased Arrays

The first millimeter-wave system-on-chip for dual-band phased array applications is presented as a proof of concept for K-/Ka-band (20/30 GHz) satellite communication on-the-move applications. Each chip includes four transmit (Tx) and two receive (Rx) channels working at Kaand K-band, respectively. The proposed architecture enables a half-duplex operating mode in two different bands. Its development was driven taking into account the integration into a realistic Tx/Rx shared aperture phased array architecture. Full amplitude and phase control are provided for each channel with high granularity (65536 states). The measured results demonstrate the validity of the proposed chip architecture, even though the channel output power and the noise figure (NF) are not in full agreement with the simulations. In Tx mode, the channel provides 9.47 dB of gain with 4.19-dBm output power at 1-dB compression. In Rx mode, the channel gain is 21.6 dB with an NF of 5 dB. In a scenario with 5.265° phase steps and 8-dB amplitude tapering capability, the amplitude and phase root-mean-square (RMS) errors within the Tx bandwidth (29.5-30.8 GHz) are equal to 0.52 dB and 3.74°, respectively. The amplitude and phase RMS errors in the Rx bandwidth (19.7-21 GHz) are equal to 2.05 dB and 12.11°, respectively. The chip consumes 340 mW in Tx and 242 mW in Rx mode and occupies 3.3 × 3.5 mm².

I. Introduction

Satellite communication (SatCom) systems, operating at K-/Ka-band, have been identified as pillars of the “future internet” architecture, which is expected to merge the patchwork of mobile and fixed networks into a single communication infrastructure. Therefore, it will be essential to develop user terminals for satellite communications on the move (SOTM), which can be easily integrated on land, maritime, or airborne vehicles. They should provide coverage over a wide scanning range, high angular scanning resolution, and simultaneous up- and downlink operation. Phased arrays are the most viable solution to meet such requirements. However, in this context, their architecture becomes particularly complex, posing significant challenges in terms of integration. They require a transmit (Tx)/receive (Rx) module per array element to provide amplitude and phase control along with an amplifying stage. Although in the past several solutions at similar frequencies were designed employing GaAs [1]–[4] or InP [5], [6] building blocks, these semiconductor technologies cannot be used for applications requiring higher integration. In fact, SiGe BiCMOS is a competitive technology here due to its ability for high integration density. For example, in [7], a 30–38 GHz 4-b phase shifter integrated with a low-noise amplifier (LNA) in a 0.12- SiGe BiCMOS process was proposed. A similar configuration, combined with a variable-gain amplifier (VGA) was also demonstrated for single-ended and differential Ka-band phased array modules [8]. A Tx/Rx module operating in Ka-band was proposed in [9] combining on the same chip a power amplifier (PA), an LNA, a single 4-b phase shifter cascaded with VGA, and a pair of single-pole-double-throw (SPDT) switches.