The Analysis And Improvement Of FTTH Optical Receiver

The requirement of rapid increased information transmission led to many advances in optical networks. The CATV networks have attracted more and more attention since they can deliver over 80 video channels, and have the potential capability of providing other digital data transmission service. As a key component, the CATV optical receivers will play an important role in the CATV networks. Most of the commercial CATV optical receivers have the disadvantages of low sensitivity and high nonlinear distortions because ordinary PIN photodiodes are used in these receivers. It is necessary to improve the performance and decrease the costs of the receivers so that they can be applied in the fields of FTTH. In order to achieve this aim, some works have been done in this paper. First, the factors that influence the performance of the receivers, including photodiodes, matching circuit, forward amplifiers and RF amplifier modules, are discussed considerably. Second, based on the GJS862 optical receiver, a new sample receiver has been produced by using excellent RF amplifier modules and PIN photodiodes, as well as designing pre-amplifying and power amplifying circuits carefully. Third, experimental results show that the new receiver has a dynamic range of up to -8~0dBm, and power wastage as low as 3W. As a result, the improved optical receivers will be well suited for the CATV networks because it decreases the installation and maintenance costs.