Noise performance of a preamplifier for high-speed optical receiver front-ends
This paper reports on an optical receiver employing a p-i-n diode and a GaAs HBT monolithic microwave integrated circuit (MMIC) distributed preamplifier combination. The design is the first to have a photodiode mounted directly on me MMIC chip. The p-i-n preamplifier displays a measured average equivalent input noise current density of 24 pA/Hz. Good agreement is obtained between the predicted and measured noise performance. The monolithic eight-stage distributed amplifier is implemented using Mortel's GaAs HBT (f T = 70 GHz) process, and makes use of a coplanar waveguide regime having a large input impedance optimized for noise performance and bandwidth. The p-i-n photodiode employed is an mGaAs vertically illuminated structure, also from Nortel. While the voltage gain of the amplifier displays a 3 dB bandwidth extending to nearly 40 GHz, the bandwidth of the complete optical receiver is found to be only 22 GHz. Packaging effects are believed to be responsible for this shrinkage.
|Keywords||Distributed amplifier, GaAs HBT, p-i-n diode, Photoreceiver, Preamplifier|
|Journal||Canadian Journal of Electrical and Computer Engineering|
Tian, X. (Xizhen), Roy, L, & Freundorfer, A.P. (2005). Noise performance of a preamplifier for high-speed optical receiver front-ends. Canadian Journal of Electrical and Computer Engineering, 30(1), 49–54. doi:10.1109/CJECE.2005.1532606