This paper presents a novel frequency doubler that further enhances the superior performance of solutions based on the Gilbert-cell mixer. A novel scheme is proposed to operate the cell with a 25 % LO duty-cycle. This technique boosts the conversion gain by generating a square-wave like output current. Moreover, the use of a quadrature generation block, commonly adopted in mixer-based frequency doublers, is not required, thus improving the operation bandwidth. The duty-cycle is automatically regulated by a low-frequency feedback loop which ensures optimal operation against input power and PVT variations. The performance of a test chip in a SiGe - BiCMOS process is presented. With a low supply voltage of 1.5 V, the chip achieves 6 dB conversion gain, 5.7 dBm peak P-sat and 17 % power efficiency at 20 GHz. The doubler delivers P-sat > 3 dBm over more than one octave bandwidth. Experimental results compare favorably against previously reported frequency doublers in the same frequency range.
A K-band Gilbert-Cell Frequency Doubler with Self-Adjusted 25% LO Duty-Cycle in SiGe BiCMOS Technology
Piotto, L;Mazzanti, A
2022-01-01
Abstract
This paper presents a novel frequency doubler that further enhances the superior performance of solutions based on the Gilbert-cell mixer. A novel scheme is proposed to operate the cell with a 25 % LO duty-cycle. This technique boosts the conversion gain by generating a square-wave like output current. Moreover, the use of a quadrature generation block, commonly adopted in mixer-based frequency doublers, is not required, thus improving the operation bandwidth. The duty-cycle is automatically regulated by a low-frequency feedback loop which ensures optimal operation against input power and PVT variations. The performance of a test chip in a SiGe - BiCMOS process is presented. With a low supply voltage of 1.5 V, the chip achieves 6 dB conversion gain, 5.7 dBm peak P-sat and 17 % power efficiency at 20 GHz. The doubler delivers P-sat > 3 dBm over more than one octave bandwidth. Experimental results compare favorably against previously reported frequency doublers in the same frequency range.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.