useful bandwidth造句

• Unlike pilots which are used for estimation of channel and must waste some useful bandwidth , the ppss , whose power can be boosted 3db or 6db to suppress efficiently the additive noise , is useful data transmitted , thus efficiency of the ofdm has been increased
  与用于做信道估计的导频符号不同， ppss传输的是有用的数据，因此提高了系统的带宽利用率， ppss的平均功率增加3db或6db可有效抑制信道的加性高斯噪声。