| 1. | Communications technologies address the issue of how signals can be transmitted and properly received over a noisy channel 通讯技术旨在解决如何透过噪音讯道传送及准确接收讯号的问题。 |
| 2. | At first , the error model of the vector quantization , watermarking embedding and the noisy channel were established and further the simplified model was given 为了用蚁群算法进行优化,首先建立了矢量量化、水印嵌入及通过噪声通道的误差模型,并给出了简化模型。 |
| 3. | The models of unconditional security from quantum channels and noisy channels are two typical methods now . two parties begin the secret - key agreement over a public channel 目前最典型的方法是利用有扰信道或量子信道建立无条件安全模型,通信双方在公共信道上进行密钥协商。 |
| 4. | New york , april26 - 27 , 1999 , pp . 812 - 816 . 3 wang y , orchard m t , reibman a r . multiple description image codingfor noisy channels by pairing transform coefficients . in 在多描述编码中,编码器对同一信号源产生具有同等重要性的两个或多个码流称为描述,以使这些描述同时遭遇传输失效的几率降到极小。 |
| 5. | The is offers robustness neceesary for noisy channels . the video coding system discussed in this part can transform the pal video signal to mpeg - 2 ts . it offers an effective method for video signal transmitting 本文研制的mpeg - 2编码板可以将pal制视频信号压缩为mpeg - 2传输流,为电视信号的传输提供了一种有效的途径。 |
| 6. | Convolutional coding is a coding scheme often employed in deep space communications and recently in digital wireless communications . it offers an alternative to block codes for transmission over a noisy channel 卷积码被运用于卫星通信和无线通信系统中,它提供了一种不同于分组码的在噪声信道下传输信息的一种编码方案。 |
| 7. | Turbo code , which utilizes the condition of random coding and decoding of shannon noisy channel coding theorem , has obtained the performance near to shannon theoretic limit . the performance of turbo code is the best one in all presented coding methods Turbo码由于很好地应用了shannon有噪信道编码定理中的随机性编译码条件而获得了接近shannon理论极限的译码性能。 |
| 8. | According to horodeckis , the coherent information of entangled state is supposed to be the lower bound of one - way distillable entanglement . this postulation is called hashing inequality , which is crucial in proving noisy channel coding theorem . it is shown that there are no direc 根据horodecki等人的研究,纠缠态的相干信息推测是单向蒸馏纠缠的下限,该假设称为hashing不等n式,对证明有噪信道编码定理至关重要 |
| 9. | Because the watermark embedding and the noisy channel were directly related to the codeword index order in the model , at the same time deciding the codeword index was a np - hard problem typically , so the ant colony algorithm was introduced to optimize it in order to make the bit error rate lower and the embedded watermark more invisible 在该模型中,由于水印嵌入和通道噪声直接与码字索引相关,所以该模型误差由索引值决定,又由于码字索引的确定是np难度问题,故引入蚁群算法对其优化是方便的,优化目标是降低误码率和使不可见性达到最佳。 |
| 10. | Information - theoretically secure secret - key agreement is the key to make perfect security . the models of unconditional security from quantum channels and noisy channels are two typical methods now . once the secret - key has been agreed over a public channel , one can use the key to encrypt messages by using one time pad 现在通常的做法是通信双方使用有扰信道或量子信道建立无条件安全模型,然后在公开认证信道上交互信息进行密钥协商,通信双方把协商之后的安全的密钥作为双方共享的密钥使用一次一密体制进行保密通信。 |