Design Of RoF Analog Directly Modulated Laser Driver In SiGe Technology

Mobile communications and optical fiber communication as the two widely used communication technology have been toward the development of higher transmission rate. At present, the commercial LTE (Long Term Evolution) mobile communication network has more than the speed of 100 Mbps in theory,100 Gbps optical fiber communication network has also been commercially available. RoF (Radio over Fiber) has become an important direction of the development in communication network technology, which combines the features including the high speed of optical fiber communication and the flexible and convenient mobile communication. The Analog Direct Modulation RoF technology directly transmits the Analog-RF signal which has been modulated on the optical fiber channel, without the need for analog-to-digital conversion process.Laser is an indispensable RoF communication system light source device, which generates waves that are used to carry data information. The light energy emitted by the laser is supplied by the driver, and the driver is responsible for the linear amplification of the radio frequency modulated signal in the Analog Direct Modulation RoF system. In this thesis, I research and design the laser driver which is applied to the Analog Direct Modulation RoF system.The research background and development status of RoF is introduced in this thesis, and the problems in the design of the drive, and studies the design ideas and solutions are analyzed.The IBM 130nm SiGe BiCMOS process is used to design two 5GHz single-end two-stage amplifier RoF analog direct modulation laser driver. One of the drivers is a monolithic integrated input/output-matching network, while the other is not integrated with matching network. The former is the use of 8XP process, and the latter uses 8HP process. The main difference between the two processes is the performance of HBT.This thesis demonstrates the schematic diagram of the front-end circuit, the layout design and the post simulation results of two 5 GHz RoF analog direct modulation laser driver. In single supply voltage of 1.8V,8XP driver achieves 22dBm of OP1dB and 16.8% of maximum PAE. Variation of power gain is less than 0.4 dB during input power from the-8dBm-0dBm, and the maximum power gain is about 20.74dB, simulation results satisfies the specification requirements, the chip area is about 1420 ?m×976?m.8HP driver chip area is about 935 ?m× 900?m.