针对我国待建的110 m全可动射电望远镜(QTT)的工作特点，以提高主反射面精度为目标，以最佳吻合抛物面为拟合标准，分析了传统结构方案致使精度较低的本质原因为反射体变形不均匀，主要源于如下三方面：主反射面存在集中荷载作用、背架结构支承方案不合理、背架结构体系空间受力性能不佳。基于此，改变副反射面撑腿坐落位置，对背架结构采用三角锥、四角锥相结合的网架式结构方案，并对其引入一种高度极对称的伞撑式支承方案。最终提出的全可动望远镜结构总体方案显著提高了主反射面精度，其RMS最大值可降至0.306 mm；相较目前世界最大的全可动射电望远镜GBT而言，其反射面积增大了10%，精度提高了12.6%，自重降低了40%，其研究成果达到国际先进水平。

Aiming at the 110 m fully-steerable radio telescope(which is called QTT for short ) to be built in the future, in order to improve the main reflector precision, the traditional structural concepts were analyzed based on the best fit paraboloid. It is the uneven deformation of the reflector that results in the lower precision. It is mainly due to the following three aspects: the concentrated loads exist on the main reflecting surface, the back frame supporting system is unreasonable and the back frame structure has a poor performance. Based on this, the catching points of the secondary reflector supporting legs were changed, the space truss structure combining cones and quadrangular pyramids were adopted as the back frame structure design, and a kind of polar symmetry umbrella structure was proposed as the supporting system for the back frame structure. Finally the introduced scheme for the fully-steerable radio telescope significantly improved the main reflector precision, its maximal RMS was reduced to 0.306 mm. Compared with the fully-steerable radio telescope GBT which has the largest diameter in the world, the reflective surface area of QTT increases 10%, the surface precision improves 12.6% and the total weight decreases 40%. The QTT performance reaches the international advanced level.