求高手翻译,200分!

如果好的话还会追加分数!
For adaptation of coding and modulation, our protocol can use an error count or iteration count, each of which can be obtained easily for each packet that is decoded correctly. A high rate CRC code is used to verify the correctness of the decoded packets. The error count for a packet that decodes correctly is the number of binary symbol errors at the output of the demodulator. One way to obtain the error count is to encode the information bits from a correctly decoded packet and compare them with the binary representations of the demodulator hard decisions for the packet. The intent is to count the number of binary symbol errors that would have occurred if there were no decoder in the receiver. The iteration count is the average number of decoder iterations per packet among the packets that decode correctly. The decoder can easily report the number of iterations that it made for a packet that has been decoded and verified for correctness. A demodulator statistic is used by our protocol for certain secondary modes of operation, such as the power-adjustment phase at the start of a session that will use a new frequency band. The protocol also uses a demodulator statistic to adapt the power if further adaptation of coding and modulation cannot offset an increase that has occurred in the propagation loss.

此答复请楼主绝对放心,我看你也是十级高手,定能明鉴。
COGNITIVE radios are ideally suited for use in dynamic spectrum access networks in which there may be large variations in channel conditions from one session to the next. Such variations are common in networks that operate in a fixed frequency band, but the variations are more severe if the frequency band is changed for consecutive sessions. Each radio in a dynamic spectrum access network must be aware of its communication environment, and it must provide the information that other radios need in order to communicate with it efficiently. This information should besimple, easy to derive, and easy to send to neighboring radios. We focus on the information needed to adapt the error-control coding, modulation, and transmitter power for half-duplex packet transmissions.
认知无线电能理想地适用于动态谱接入(访问)网,在这种网络中,信道条件从一个会话(作业阶段)到下一个会话可能存在很大变化。这样的变化在以固定频带工作的网络中是常见的,但是如果频带对连续的会话来说是变化的,那么这样的变化就会更严重。在一个动态谱接入网中的每一无线电必须感知到自己的通信环境,而且它必须提供其它无线电所需的信息,以便与其有效地通信。此信息应该是简单的,容易导出的,以及容易发送到临近无线电的。我们重点讨论为适应错误控制编码、调制、以及半双工包传输用发射机功率所需的信息。
A new session begins when one radio, referred to as the source, has a collection of packets to send to another radio, the destination. At the start of a new session, which may be in a different frequency band than the previous session, the protocol must adjust the transmitter power to provide reliable communications with minimal energy consumption and minimal interference to other radios. As the session progresses, the protocol must adjust the transmissions to compensate for changes in channel conditions. Our results demonstrate the extent to which the adaptive transmission protocol can rely only on code-rate adaptation to offset increased propagation loss. We show that when the cognitive radios must compensate for very large variations in the channel conditions, it is necessary to adapt the modulation also. Power increases are employed by our protocol only if the channel deteriorates so much during a session that changes in coding and modulation cannot provide enough compensation, which occurs very rarely.
一个新的会话开始于一个作为源的无线电拥有一批包要发送到另一无线电(目的地)时开始。在可能处于与前一会话不同频带的新的会话开始之际,协议必须调节发射机的功率,以便为可靠的通信提供最小的能耗及对其它无线电最小的干扰。随着会话的进展,协议必须调节传输来补偿信道条件的变化。我们的结果证明了自适应传输协议能够仅依赖编码率自适应来弥补增加了的传播损耗的程度。我们证明了,当认知无线电必须补偿信道条件很大的变化时,也就必须自适调制。只要信道在一次会话过程中恶化到编码和调制的变化不能提供足够的补偿,我们的协议就采用功率的提高,不过这种情况很少发生。
The throughput performance of our protocol is compared with theoretical limits that are derived from considering ideal protocols and applying Shannon capacity results. We demonstrate that our protocol performs nearly as well as an ideal protocol that is given perfect channel-state information. The modulation formats that are available to the adaptive transmission system span a range from bandwidth-efficient modulation to power-efficient modulation, which permits the adaptation to compensate for large changes in propagation loss. In order to keep the complexity low, bit-interleaved coded modulation is employed to obtain each combination of coding and modulation that is used by the adaptive transmission protocol. In this approach, it is simple to change the code and modulation independently, because the error-control codes are not tailored to specific modulation formats.
我们的协议的吞吐量性能与理论极限做了比较,理论极限则通过考虑理想的协议和采用Shannon(香农)容量结果推得。我们证明了,我们的协议的性能和被提供理想信道状态信息的理想协议几乎一样好。可用于自适应传输系统的调制格式的范围从带宽-有效调制跨越到功率有效调制,这就使自适应能补偿传播损耗大的变化。为了使复杂性保持在低水平,采用位-间插复用的(interleaved)编码调制来获得为自适应传输协议所采用的编码和调制的每一组合。用这一方法,独立地改变编码和调制就很简单,因为错误控制代码不是为特定的调制格式定制的。
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第1个回答  2008-11-26
为编制程序和模块化的适应,我们的协议可能使用错误计数或叠代计数,其中每一可以为每个小包容易地得到恰当地被解码。 一个高速率CRC代码被用于核实被解码的小包的正确性。 恰当地解码的小包的错误计数是二进制标志错误的数量在解调器的产品。 一种方式获得错误计数将输入从一个恰当地被解码的小包的信息位和他们与解调器决策的二进制表示法比较小包的。 意向是计数将生成二进制标志错误的数量,如果没有在接收器的译码器。 叠代计数是译码器叠代的平均数量每个小包在恰当地解码的小包之中。 译码器可能容易地报告它为小包做为正确性被解码了并且被核实了叠代的数量。 我们的协议使用解调器统计为某些次要运作方式,例如力量调整阶段在将使用一个新的频带的会议的开始。 协议也使用一个解调器统计适应力量,如果编制程序和模块化的进一步适应不可能抵销在传播损失发生了的增量。

为适应编码和调制,我们的协议可以使用一个错误计数或迭代计算,每个可轻松地为每个数据包解码是正确的。高利率CRC码是用来验证正确的解码包。错误计数的数据包解码是正确的数目的二进制符号错误的输出解调器。方式之一,以获取错误计数编码比特的信息从一个正确的解码包和比较它们的二进制申述的解调艰难的决定的数据包。其意图是,计数的二进制代码错误可能会出现如果没有解码器的接收器。迭代计数的平均数目迭代解码器每包之间的数据包解码正确。解码器可以很容易地报告迭代次数,它为一包已被破译和核实的正确性。解调统计是我们所使用的协议的某些中学的操作模式,如电源调整阶段开始时,会议将使用新的频段。该协议还采用了解调统计适应能力是否需要进一步调整编码和调制不能抵消增加了发生在繁殖的损失。
第2个回答  2008-11-25
为适应编码和调制,我们的协议可以使用一个错误计数或迭代计算,每个可轻松地为每个数据包解码是正确的。高利率CRC码是用来验证正确的解码包。错误计数的数据包解码是正确的数目的二进制符号错误的输出解调器。方式之一,以获取错误计数编码比特的信息从一个正确的解码包和比较它们的二进制申述的解调艰难的决定的数据包。其意图是,计数的二进制代码错误可能会出现如果没有解码器的接收器。迭代计数的平均数目迭代解码器每包之间的数据包解码正确。解码器可以很容易地报告迭代次数,它为一包已被破译和核实的正确性。解调统计是我们所使用的协议的某些中学的操作模式,如电源调整阶段开始时,会议将使用新的频段。该协议还采用了解调统计适应能力是否需要进一步调整编码和调制不能抵消增加了发生在繁殖的损失。
相关产出除以规模最大,平均调制符号中的数据包。比statisticfor个人的象征最初是引进antijam通报Viterbi译码,并已采用多种用途,其中包括软判决译码。的平均比率的统计资料中的符号一包可用于任何调制格式,但自适应传输通常最适合的信号台中等规模大,如nonbinary正交和双正交调制或调制。
每个统计中使用的一个简单的测试间隔来决定的参数,用于在未来的传输。该测试可用于在目的地或来源;在两种情况下,只有少数几个比特的信息需要在每一个确认数据包。对于半双工数据包传输,也有延迟的决心适应的统计数据和传输数据包这是他们的申请,但是,在一个特设的网络,我们认为其主要目的是自适应传输,以弥补慢慢变信道条件下,一种信念所支持的结论英寸拖延对我们的协议是不大于任何其他协议,可halfduplex数据包传输,包括协议,依赖于估计,信道增益。

参考资料:http://www.hao123.com/ss/fy.htm

第3个回答  2008-11-25
For adaptation of coding and modulation, our protocol can use an error count or iteration count, each of which can be obtained easily for each packet that is decoded correctly. A high rate CRC code is used to verify the correctness of the decoded packets. The error count for a packet that decodes correctly is the number of binary symbol errors at the output of the demodulator. One way to obtain the error count is to encode the information bits from a correctly decoded packet and compare them with the binary representations of the demodulator hard decisions for the packet. The intent is to count the number of binary symbol errors that would have occurred if there were no decoder in the receiver. The iteration count is the average number of decoder iterations per packet among the packets that decode correctly. The decoder can easily report the number of iterations that it made for a packet that has been decoded and verified for correctness. A demodulator statistic is used by our protocol for certain secondary modes of operation, such as the power-adjustment phase at the start of a session that will use a new frequency band. The protocol also uses a demodulator statistic to adapt the power if further adaptation of coding and modulation cannot offset an increase that has occurred in the propagation loss.
对于编码和调制的自适应来说,我们的协议可以采用一个错误计数或重复计数,它们中的每一种对于正确解码的每个包来说都可容易获得。对应于一个被正确解码的包的错误计数就是在解调器输出端处的二进制符号错误。得到错误计数的一种方法是将来自一个正确解码的包的信息位译码,并将它们与解调器对包的硬判决的二进制表示进行比对。 其意图是计数如果在接收器中没有解码器时可能已经发生的二进制符号错误的数目。重复计数是在正确解码的所有包中每一个包的解码器重复(迭代) 的平均数。解码器会容易地报告出它为一个业已解码并已验证了准确性的包所进行的重复(迭代)数。一种解调器统计被我们的协议所采用而用于一定的二次(辅助)工作模式,例如一个将采用新的频带的会话(作业阶段)开始时的功率调节方面。如果编码和调制的进一步自适应不能弥补传播损耗业已产生的增加,此协议还会采用一种解调器统计来适应此功率。本回答被提问者采纳
第4个回答  2008-11-25
对于编码和调制的适应来说, 我们的草案能使用一个错误数或者迭代数,每个数都可以容易地从被正确地译解的信息包中获得。 一条高的比率科林斯无线电公司代码用来证实被译解的信息包的正确性。被正确地译解的信息包中的错误数据是在解调器输出时的二进制符号。 获得错误数据的一种方法是把被正确译解的信息包的讯息进行编码并用解调器的二进制进行比较。这样做的目的是如果在接收者里没有译码器,就去计算会发生的二进制的符号错误的数量。迭代数字是在译码器中每一个信息包被正确地译解出来的反覆出现的平均数。译码器能容易报告迭代数的数量,这样有利于那些已被正确的译解和检验的信息包。由於我们的协议,解调器统计被用于一些次要工作模式,例如在会议一开始时的功率调整阶段,将使用一根新频率带。如果更多的编码和调制的改写不能补偿已经在传播方面增加的损失,草案也使用解调器统计去改写功率 。
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