Question

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翻译一段英文
The next results demonstrate the performance of our adaptive coding and modulation protocol when used in conjunction with a protocol that adapts the transmitter power only when further changes in modulation and coding cannot accomplish the desired objective. The power is increased only if the most robust code-modulation combination is inadequate; it is decreased only if the code-modulation combination with the highest information rate is stronger than necessary. We employ a session model in which the source must deliver 500 KB of information to the destination over a channel with a fixed but unknown propagation loss, which requires that the destination must decode correctly approximately 1250−4250 packets, depending on the code-modulation combination that is used by the source. The session duration is defined as the number of time units required to complete the session. The results in Fig. 5 illustrate the power increment as a function of the excess propagation loss for the adaptive coding and modulation protocol. The power increment is the amount in dB by which the transmitter’s power is increased (or decreased,if it is negative) by the protocol. For comparison, the power increments for ten fixed code-modulation combinations are also shown. After the initial power adjustment has been completed, the adaptive transmission protocol begins operation at the reference point in the curve in Fig. 5, which corresponds to a power increment of 0 dB and an excess propagation loss of 0 dB. These reference values are relative to the transmitter power level and propagation loss at the time that the poweradjustment protocol hits its stopping condition. After that, as the excess power varies between 0 dB and 18 dB, the adaptive transmission protocol follows the horizontal line by changing the coding and modulation but not changing the power (the power increment remains constant at 0 dB). As long as the
excess propagation loss does not exceed 18 dB during the session, the adaptive transmission protocol does not increase
the transmitter power. As discussed in Section V, the adaptive
transmission protocol can compensate for propagation loss
increases that are much greater than 18 dB without increasing
the transmitter power if 64-biorthogonal modulation and 64-
QAM are added to the set of modulation formats. In contrast,
we see from Fig. 5 that each fixed code-modulation requires
that the power be increased to match each increase in the
propagation loss that occurs during the session. It is likely
that the amount of power increase that is permitted will be
limited in a dynamic spectrum access network because of the
disruption that higher-power transmissions may cause to other
sessions. If power increases are desired and permitted, the
protocol can automatically adapt the power if the most robust
code-modulation cannot handle the increase in the propagation
loss.

Answer 1

后面的结果证明了我们的自适性编码和调制协议在与一个协议（此协议只在调制和编码的进一步变化不能完成希望的目标时自适应发射机功率）一起使用时的性能。功率只有在最鲁棒的编码－调制组合作用不充分时才增加；功率也只有在具有最高信息速率编码－调制组合强于需要时才降低。我们采用了一种会话模型，其中，源必需通过传播损耗固定但未知的信道向目的地提供500 KB的信息，这要求目的地必须根据源所用的编码－调制组合准确解码1250～4250个包。会话持续时间定义为完成会话所需的时间单位数。图5中的结果图示说明了功率增量与作为自适性编码和调制协议额外传播损耗的函数关系。功率增量是以dB表示的，由协议提高（或降低，如果它是负值的话）的发射机功率的量。对应10个固定编码－调制组合的功率增量也被示出，以供对比。在初始功率调节业已完成以后，自适性传输协议在图5曲线的参考点处开始工作，该点相应于0 dB的功率增量和0 dB的额外传播损耗。这些参考值与发射机的功率电平及功率调节协议碰到停止条件时的传播损耗有关。在那以后，随着额外功率在0 dB和18 dB之间变化，自适性传输协议就依靠改变编码和调制，但不改变功率（功率增量保持在0 dB不变）而沿一条水平线行进。只要额外传播损耗在会话过程中不超过18 dB，自适性传输协议就不会使发射机功率提高。如第5节中讨论的那样，如果我们把64-双正交调制和64-QAM加入调制格式的集合中，自适性传输协议不需要提高发射机功率就能够补偿大大超过18 dB的传播损耗增加。相反，我们从图5看到，每个固定的编码－调制都要求功率提高以与发生在会话过程中传播损耗的每一增加相匹配。很有可能，允许的功率增加量在动态频谱接入（访问）网中将是有限制的，因为较高功率的传输可能对其它会话引起破坏（离散）。如果功率的提高是希望的和允许的，那么如果最鲁棒的编码－调制不能处理传播损耗的增加，协议就会自动适应功率。

Answer 2

下次结果表明，我们的业绩自适应编码和调制协议一起使用时的协议，适应发射机功率只有在进一步的修改编码和调制无法完成预期目标。功率增加，只有最强大的码调制组合是不够的，它是只有减少代码调制结合的最高信息速率比预期更强劲必要的。我们聘用了会议模式，在这种模式的来源必须提供500 KB的资料到目的地的一个渠道，固定，但未知的传输损耗，这就要求目的地必须正确解码包大约1250-4250 ，根据代码调制组合所使用的来源。这次会议会期是指一些单位要求的时间完成了会议。结果图。第5说明增量的权力作为一种功能过剩的传输损耗的自适应编码和调制协议。电力增量的数额分贝，其中发射机的功率增加（或减少，如果是负面）的协议。相比之下，电力增量的10固定码调制组合也显示。在最初的功率调整已经完成，自适应传输协议开始运作，参照点的曲线图。 5 ，这相当于一个功率增量为0分贝，超出传输损耗为0分贝。这些参考价值观念是相对的发射机功率水平和传输损耗的时间， poweradjustment协议安打其停止条件。在此之后，作为电力过剩之间0分贝和18分贝的自适应传输协议如下横向线通过改变编码和调制，但不改变功率（功率增量保持恒定在0分贝） 。只要过量繁殖的损失不超过十八分贝会议期间，自适应传输协议不会增加发射机功率。正如在第五节，自适应传输协议可补偿传输损耗增加是远远大于未经十八分贝增加发射机功率，如果64双正交调制和64 - QAM调制添加到设定的调制格式。与此相反，我们看到从图。五，每个固定码调制要求电力提高到符合每个增加传输损耗发生在会议期间。很可能数额增加的权力是允许将仅限于一个动态频谱接入网络，因为中断，高功率传输可能会导致其他会议。如果功率增加的期望和许可，协议可以自动适应电源，如果最强大的码调制无法处理增加的繁殖损失。