coded passive reflector antenna

例句：

1. 1. The coded message was sent via a secure email.
   通过加密邮件发送了密文信息。
2. 2. The security system uses a coded system to prevent unauthorized access.
   安全系统使用密码系统防止未经授权的访问。
3. 3. The coded instructions were written in a language that only the programmers could understand.
   代码指令是用只有程序员能理解的语言写的。