...下文更好地进行说明，我们将认知无线电中的基本术语介绍如下， u 目前所有的频谱可分为两大类： 1．授权频谱（Licensed Bands）：指那些被通信运营商所拥有的授权频段，通信运 营商需要为这些频段支付使用费用。
双语例句
1
The utilization rate of licensed spectrum is very low in the time domain, frequency domain and space domain, while the unlicensed band is overcrowded seriously.
大部分授权频段在时域、频域和空间域的利用率很低，而公共频段出现了严重的频谱拥挤。
2
Do not use if imprinted cap band is broken or missing. If symptoms persist for more than 7 days or worsen, contact a licensed health care provider.
如果瓶盖带子丢失或是破损请不要使用，如果症状持续超过7天或是恶化，咨询执业健康专家。
3
Do not use if cap band is missing or broken. If you are pregnant or nursing, consult a licensed health care professional before using this product.