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  _____    __   __    ______   _    _     ______  
 |__  //   \ \\/ //  /_   _// | || | ||  /_   _// 
   / //     \ ` //     | ||   | || | ||    | ||   
  / //__     | ||     _| ||   | \\_/ ||   _| ||   
 /_____||    |_||    /__//     \____//   /__//    
 `-----`     `-`'    `--`       `---`    `--`

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Text this: Secure wireless transmission without keys : a physical layer approach