The idea of inflatable spacecraft is not new. The Echo I - NASA's first communication satellite - was essentially 100-foot-wide Mylar balloon that reflected radio transmissions from the ground.

充气式航天器并不是什么新颖的想法，NASA的第一颗通讯卫星回声1号实际上就是一个宽30米的聚酯薄膜大气球，它是用来发射来自地面的无线电广播的。

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IntroductionIn the communication systems, echo and noise will seriously affect speech communication quality, such as IP telephone, videophone and hand-free digital cell phone systems etc.

引言在通信系统中，例如IP电话、可视电话及免提数字蜂窝电话系统中，回声和噪声会严重影响通信质量。

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So acoustic echo cancellation (AEC) technique has become a hot issue of competition in the famous communication company all over the world.

因此，回波消除技术也就成为世界各大通讯公司竞争的热点技术之一。

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This card also includes the high-quality beam-forming microphone, allowing advanced voice communication without the need for the headset by leveraging CrystalVoice Echo Cancellation, CrystalVoice Focus and CrystalVoice Active Noise Reduction.

ENGADGET: Creative doles out Sound Blaster gaming headsets, Recon3D audio platform / sound cards