As the transmissionlength reaches a certain distance, DC transmission becomes economically attractive over ac.
当输电距离足够长时，直流输电的经济性将优于交流输电。
2
Message size and length can affect the performance of the application that processes the message, and the network time of data transmission.
消息大小和长度会影响处理消息的应用程序的性能以及网络数据传输时间。
3
If the length of its cyclic prefix is larger than the delay spread of transmission channel, we can get a simple frequency equalizer to demodulate OFDM signal.