The Application Of Digital Optic Fiber Repeater Station In Lu’an

The CDMA ditital optic fiber optic repeater is a kind of new designed CDMA station.It’s made of two part:one is digital acquisition unit(DAU),the other is digital remote unit(DRU).The DAU is near the base station,which collect the CDMA signal,and transmit the signal to The DRU by optic fiber.The DRU is setup far from the DAU, where the CDMA radio is very poor.Lu’an city is in the west of Anhui province,most of the land is mountain. The coverage is very poor. Telecommunication took a great deal of the investment innetwork coverage. Lu’an Telecom have build 703 CDMA base station in 3 years. But still cannot satisfy the demand of communication in Dabie Mountain area. The more effective ways of construction is needed.CDMA is a kind of self interference system, the uplink capacity is limited by interference. Digital repeater low noise characteristic, which is very suitable for application in CDMA system theoretically.Digital optical fiber repeater is good than traditional analog repeater.From the structure, increase the digital processing unit; from the technical performance, using digital intermediate frequency and multi machine cascade, optical-bypass technology. To overcome the analog signal long distance optical fiber attenuation caused by the decline in the overall SNR shortcomings, has the long-distance transmission needs large dynamic range, low noise.Digital repeater station is a kind of new products, specific performance parameters, applications and engineering practice are less. Organized by Anhui telecommunication network optimization center, conducted a comprehensive test of digital optical fiber repeater work. Send measured the manufacturers of the overall level, representing the basic domestic fiber-optic repeater digital level. This test, obtained the related equipment first hand information, mastered the types of equipment performance characteristics.In the subsequent network planning, optimization, make full use of the digital optical fiber repeater related experience. In some mountain areas cover, cover, cover along the highway high-speed rail projects, bold use of new equipment, obtained obvious achievements. In a mountainous area coverage, using the base station joint technology, with a small amount of cable driven multiple repeater station, along the residential layout site. Using the low noise characteristics, a single CDMA sector can take 6 station remote machine, greatly expanded the coverage radius.The creative application of its" delay adjustment" function, automatically adjust the source base station parameters. Successful completion the handoff between the repeater station, as well as the handoff between repeaters and base station. Especially" Hefei-Wuhan high-speed railway tunnel covering Anhui special project", the overall design of the digital optical fiber repeater coverage tunnel. Train to 250Km/S speed driving, can guarantee the user voice communication is clear without dropping, high-speed data communication without delay.Hope that more excellent engineers to use the new product, summed up more and more reasonable, more effective method of use. Let digital optical fiber repeater as soon as possible to become a basic product in the CDMA network.