基于对数字电视地面传输系统复杂度和性能代价的综合考虑，提出以符号变换为基础的IC I自消除模块替换卷积码模块。

Based on synthesis consideration of complexity and performance cost, this paper proposed a modified scheme of using the ICI self-cancellation module to replace the convolutional coding module.

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当然，还有很多挑战，例如，减轻气球的重量，处理风的问题，设计最理想的系统传输能量到地面。

Of course, there are still challenges, such as reducing the weight of the balloons, dealing with wind, and designing the optimal system for transporting the energy down to the surface.

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在目前经济和技术条件下，只能选择地面通信系统传输信号。

Under the present economic and technological condition, we can only use ground communication system to transmit signals.

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