A 5.8 GHz Mixer using SiGe HBT Process

DSRC provides high speed radio link between Road Side Equipment and On-Board Equipment within the narrow communication area.In this paper,a 5.8 GHz down-conversion mixer for DSRC communication system is designed and fabricated using 0.8 Pm SiGe HBT process technology and RF/LO matching circuits,RF/LO input balun circuits and IF output balun circuit are all integrated on chip.The measured performance is 7.5 dB conversion gain,-2.5 dBm input IP3,46 dB LO to RF isolation,56 dB LO to IF isolation,current consumption of 21 mA for 3.0 V supply voltage and the chip size of fabricated mixer is 1.9 mm X 1.3 mm

A 5.8 GHz Mixer using SiGe HBT Process

Abstract -DSRC provides high speed radio link between Road Side Equipment and On-Board Equipment within the narrow communication area. In this paper, a 5.8 GHz down-conversion mixer for DSRC communication system is designed and fabricated using 0.8 m SiGe HBT process technology and RF/LO matching circuits, RF/LO input balun circuits and IF output balun circuit are all integrated on chip. The measured performance is 7.5 dB conversion gain, -2.5 dBm input IP3, 46 dB LO to RF isolation, 56 dB LO to IF isolation, current consumption of 21 mA for 3.0 V supply voltage and the chip size of fabricated mixer is 1.9 mm X 1.3 mm

Suppressing spontaneous polarization of p-GaN by graphene oxide passivation: Augmented light output of GaN UV-LED

International audienceGaN-based ultraviolet (UV) LEDs are widely used in numerous applications, including white light pump sources and high-density optical data storage. However, one notorious issue is low hole injection rate in p-type transport layer due to poorly activated holes and spontaneous polarization, giving rise to insufficient light emission efficiency. Therefore, improving hole injection rate is a key step towards high performance UV-LEDs. Here, we report a new method of suppressing spontaneous polarization in p-type region to augment light output of UV-LEDs. This was achieved by simply passivating graphene oxide (GO) on top of the fully fabricated LED. The dipole layer formed by the passivated GO enhanced hole injection rate by suppressing spontaneous polarization in p-type region. The homogeneity of electroluminescence intensity in active layers was improved due to band filling effect. As a consequence, the light output was enhanced by 60% in linear current region. Our simple approach of suppressing spontaneous polarization of p-GaN using GO passivation disrupts the current state of the art technology and will be useful for high-efficiency UV-LED technology