Single-Chip Frequency Multiplier Chains for Millimeter-Wave Signal Generation

Two single-chip frequency multiplier chains targeting 118 and 183 GHz output frequencies are presented. The chips are fabricated in a 0.1 mu m GaAs metamorphic high electron-mobility transistor process. The D-band frequency doubler chain covers 110 to 130 GHz with peak output power of 5 dBm. The chip requires 2 dBm input power and consumes only 65 mW of dc power. The signal at the fundamental frequency is suppressed more than 25 dB compared to the desired output signal over the band of interest. The G-band frequency sextupler (x6) chain covers 155 to 195 GHz with 0 dBm peak output power and requires 6.5 dBm input power and 92.5 mW dc power. The input signal to the multiplier chain can be reduced to 4 dBm while the output power drops only by 0.5 dB. The unwanted harmonics are suppressed more than 30 dB compared to the desired signal. An additional 183 GHz power amplifier is presented to be used after the x6 frequency multiplier chain if higher output power is required. The amplifier delivers 5 dBm output power with a small-signal gain of 9 dB from 155 to 195 GHz. The impedance matching networks are realized using coupled transmission lines which is shown to be a scalable and straightforward structure to use in amplifier design. Microstrip transmission lines are used in all the designs.