High-efficiency digital optical fiber CDMA (Code Division Multiple Access) repeater and realizing method

Abstract

The invention discloses a high-efficiency digital optical fiber CDMA (Code Division Multiple Access) repeater and a realizing method. The system consists of a near terminal device and a remote terminal device, and the near terminal device and the remote terminal device communicate with each other through transmitting digital base band signals in optical fibers. The repeater comprises a radio frequency small signal cell, a digital signal process cell, a highly efficient power amplification cell, a duplexer cell, a voltage transformation cell, a monitor cell and the like, wherein the highly efficient power amplification cell adds peak clipping and self-adaptive digital predistortion processes to the digital signal process cell by a symmetric Doherty technology so that the whole device achieves qualified linearity while improving the efficiency. The invention has the beneficial effects of effectively guaranteeing that the linearity index meets the requirements and solving the contradiction of linearity and efficiency of the radio frequency when improving the efficiency of the whole system, and also tracking the power amplification linearity feature changes due to the changes of work conditions and work environments, such as device aging, temperature change and the like, so as to always keep great linear effect.

Description

technical field [0001] The invention relates to the field of mobile communication network coverage and optimization, and mainly relates to a high-efficiency digital optical fiber CDMA repeater and a realization method. Background technique [0002] With the rapid development of mobile communication today, no matter what kind of wireless communication coverage area will produce weak signal areas and blind areas, and for some remote areas and blind areas with a small number of users, the cost of setting up analog or digital base stations is too high, and the infrastructure It is also more complicated, so it is necessary to provide a low-cost, simple-to-install, and cost-effective device with the function of a small base station - a repeater. [0003] The CDMA repeater can expand the coverage of CDMA base stations and greatly save the investment in CDMA network construction. Among them, the optical fiber repeater has good spatial isolation and no co-channel interference, so th...

AI Technical Summary

Problems solved by technology

The linearization technology and high-efficiency technology of radio frequency are contradictory. When improving the efficiency of the power amplifier unit, its linearity must be sacrificed. The adjacent channel rejection ratio (ACPR) can only reach -40dBc at 750KHz and 1.98MHz. Left or right, it is difficult to meet the system linearity index (750KHz suppression -45dBc, 1.98MHz suppression -60dBc); to meet the system's linearity index, it is necessary to reduce the efficiency of the power amplifier unit, so that its operating point retreats by more than 13dB

Images