Research On Transceiver Module Of RoF Link Based On Directly Modulated DFB Laser Device

The radio over fiber communication technology is a new and interdiscipline subject in the telecommunication field. It combines the advantages of optical fiber communication in the aspects of wide bandwidth, low cost, multiplexing availability and anti-electro magnetic interference, with the benefits of wireless telecommunication, which can provide high flexibility, broad coverage and mobility available. Hence, in the military industry and common telecommunication, RoF exhibits a wide available application prospect. More and more focus from government and relevant scholars on it, and numerous achievements get.In this dissertation,considering the requirement of application,device performance and cost,I choosed the1754C DFB laser device of Emcore company, which has the wavelength of1550nm, and the2651E PIN photon detector of Emcore company to design, fabricate and test the transceiver module of the RoF link. While the theory of RoF link, its noise character, operating character are stated in detail.The main content of this dissertation is exhibited below:1. The design of transmitter module of RoF link. It includes the power DC-DC convert circuits, automatic power control (APC) and automatic temperature control (ATC) circuits of laser device. We show the principles of the design and the components used in the design at the same time.and then we make comparison and analysis of different circuits structure based on different chips, then make the final decision. At the same time I summarized experience in the process of design, the problems appeared and their solutions.2. The design of receiver module of RoF link. It mainly contains PD diver circuits and RF low noise amplifier, we also give the principle of design and the components used in detail. Moreover, we also give some description in the field of RF transmission, impedance matching theory.3. The application research of the transceiver module of the RoF link.Based on the transceiver module I designed, I fulfilled target that the gain flatness less than2dB when frequency less than1.3GHz at matching frequency of750MHz, and gain flatness less than1.5dB when frequency range from200MHz-1.3GHz. While at the matching frequency of2.4GHz, I finally fulfilled target that the transceiver can obtain the transmission gain greater than OdB while the frequency less than2.45GHz,Thcn I give the reason why the gain curve like that. While with the carrier frequency of750MHz and2.4GHz, we use the QPSK baseband signal of different code rate in lOMbps,20Mbps,30Mbps and40Mbps to modulate he carrier and set the carrier to noise rate in30dB, then test the transmission results. And the results show the best transmission performance can obtain when the input IF power varies from-20dBm to5dBm (750MHz) and-20dBm to10dBm (2.4GHz)...