Adsl Transformer Design And Transmission Characteristics Of The Test Analysis

With the development of networks, all kinds of access technologies of internet are changing quickly. xDSL have been considered the one of the technologies which have the good fortune and feasibility in recent years. xDSL systems are built upon the existing twisted-pair telephone subscriber loop plant and can provide different bandwidth by different modulation technologies, so different transmission rates are fulfilled. ADSL is one of the xDSL and is fit for the situation of our country, because the cost of ADSL is low, and furthermore, ADSL can provide moderate bandwidth and transmission rate. The development of networks has been the motive force of developing the network transformer. The tendency of the network transformer development is miniaturization, high fidelity, high efficiency. In this thesis, the aim is to design the ADSL transformer with low loss and harmonic distortion, and analyze the characteristic of transmission. By the analysis, we can find out the factors which influence the transmission characteristic and try to optimize design the transformer from the following factors: core, coil turns, diameter of the wire, the way of winding, etc. So the characteristic can be improved. From the above analysis, we can learn about that on the one hand the magnetic core with high μi and lowηB is the premise of the transformer which transmit the signals with high bit rate and high-fidelity, on the other hand selecting the low core distortion factor and shape distortion factor is an important way to reduce the distortion of the transformer. The optimized transformer of EPX (EPO) has less several dB in THD than the transformer of EP when they have the same package size. In addition, introducing air gap in the magnetism cores can make the B and H relationship tend towards the linearization, reduce the total harmonic distortion, extend the distance of information transmission, and enhance the stability of the transformer. In different working frequency bands, the factors which influence the insertion loss of the transformer are different. Reducing the resistance of the windings by optimizing the diameter of the winding wire is an important way to reduce the insertion loss in the mid-frequency band. The leakage inductance and the distributed...