宽带卫星信道群时延的自适应均衡校正研究

在宽带卫星通信链路中，由于器件通带特性不理想和行波管放大器的工艺受限等原因使卫星信道的群时延波动较大，导致误比特性能恶化。群时延的补偿算法需要复杂的数学运算，因此工程上一般采用线性均衡对信道群时延特性进行校正。针对群时延失真严重情况下线性均衡效果下降的问题，对比研究了线性均衡、非线性均衡对信道群时延校正的性能，仿真分析了采用恒模算法的线性均衡和采用voherra模型的非线性均衡在群时延失真信道下的性能，得出了两类均衡器在群时延失真信道下的误码率性能曲线，结果表明低阶调制下采用非线性均衡可以较好的消除宽带卫星信道群时延的影响。

Adaptive Equalization Correction for Group Delay of Broadband Satellite Channel

In broadband satellite communications link, the group delay characteristic of the passband is vol- atile due to the non-ideal characteristic of the electronical component and the limitation of travelling wave tube amplifier , which leads to deterioration of the bit error performance. Group delay compensation algo- rithm requires complex mathematical operations, thus Linear equalization is usually adopted in the project implementation for correction of the group delay characteristic. Aiming at the decrease of Linear equaliza- tion effect under serious group delay distortion, the adaptive equalization is studied for its feasibility in the channel group delay correction. Sitnulation on the group delay distortion channel performance with constant modulus algorithm of linear equalization and with the model of nonlinear equalization is done, and the bit error rate performance curves by two types of equalizer under the group delay distortion channel are ob- rained. Results show that order modulation is taken with nonlinear equalization, the good performance could be achieved when low under bad group delay channel.