High-purity 60-GHz-band single-chip /spl times/8 multipliers in pHEMT and mHEMT technology

Two single-chip multiplier by eight (times8) monolithic microwave integrated circuits (MMICs) for 52-62-GHz output frequency are presented. The MMICs are designed and manufactured in commercial 0.15-mum pseudomorphic high-electron mobility transistor (pHEMT) and metamorphic HEMT (mHEMT) processes for the comparison of functionality and performance. The multipliers consist of a quadrupler stage followed by a high-pass filter, an interstage amplifier, and a doubler stage. The required output power is achieved by a buffer amplifier on the output. An output power of 8 dBm is achieved in both designs at 7.35-GHz input frequency with 0-dBm input power. The detected degradation of phase noise due to the circuit is less than 1 dB at 100-kHz offset from the carrier compared to the theoretical value for a multiplier by eight. The total power dissipation of the pHEMT design is 450 mW. The mHEMT-based multiplier has significantly lower power dissipation of only 210 mW. To the best of our knowledge, these are the first reported multiplier-by-eight MMICs based on pHEMT and mHEMT technology