查询词典 bit error ratio

It can obtain a gain of 4.5dB in channel of Gauss and 9.5dB in channel of Rice. Additionally, performance of bit error rate of component code with SM64QAM and HMsym64QAM is tested. It is concluded that the multilevel coding scheme has specific property of unequal error protection.

另外通过仿真采用标准64QAM调制和对称分级64QAM调制两种调制方式的多级编码方案的各分量码的误码性能，可以看出多级编码方案具有不等差错保护的特性。

Computer simulations show that the scheme proposed increases the transmission efficiency, and at the same time, can obtain lower error bit rate and mean square error of channel estimation than conventional OFDM systems with relative low complexity.

仿真实验表明，该策略可提高传输效率、增强系统的抗噪性能、获得比传统OFDM系统更低的信道估计均方误差和误码率，且具有较低的计算复杂度。

Computer science a bit that is used in an error detection procedure in which a 0 or 1 is added to each group of bits so that it will have either an odd number of 1's or an even number of 1's; e.g., if the parity is odd then any group of bits that arrives with an even number of 1's must contain an error

parity：简介奇偶校验位，在数据存储和传输中，字节中额外增加一个比特位，用来检验错误。它常常是从两个或更多的原始数据中产生一个冗余数据，冗余数据可以从一个原始数据中进行重建。不过，奇偶校验数。。。详情

Computer science an error detection procedure in which a bit (0 or 1) added to each group of bits so that it will have either an odd number of 1's or an even number of 1's; e.g., if the parity is odd then any group of bits that arrives with an even number of 1's must contain an error.

差错检测过程附加在一组二进制数字上的一个二进制数这一位用来使所有数字的和总是一个奇数；或者总是一个偶数。

The paper investigates both block-type pilot linear minimum mean square error algorithm and IEEE802.16 OFDM channel estimation analysis. Simulation results confirm the block-type pilot structure is more suitable for IEEE802.16 system. An optimal pilot setting algorithm, based on space frequency domain, is explored and the pilot chart is presented. The proposed algorithm finds its application in MIMO-OFDM. Simulation results show the algorithm presents a good approximation to the perfect channel state information curve, with about 2dB difference in SNR. The simulation results also demonstrate the algorithm achieves fairly high stability in the environment of fast fading, performance of the proposed algorithm is better that of pilot training channel estimation.3. Taking into account the characteristics of IEEE802.16 OFDM system, OFDM system simulation platform is constructed in Matlab, exploiting simulink as a tool. OFDM modulation and demodulation simulation system are configured on LabVIEW platform. All the system signal processing is simulated, including defining system parameters, designing modulation model, and verifying all the proposed algorithms under different environments, such as white Gaussian noise, multi-path fading, with or without guard interval etc. Bit error performance is evaluated. The research provides valid theoretical basis for practical OFDM system performance evaluation.4. Taking advantage of software radio, the paper designs a hardware platform with both 256-IFFT/FFT and 512-IFFT/FFT OFDM schemes co-existing in one platform. You can predetermine one from the two schemes to carry out almost the same model function with different system performance and parameter setting.5. Referring to IEEE802.16 standard, the paper proposes a design method for generating signals and frames suitable for laboratory investigations implemented in laboratory environment.6. Based on 6701evm digital evaluation card, combined with analogy front-end, the paper designs a DSP software model to deal with baseband signal processing. An overall OFDM scheme, with modulation and demodulation function, is accomplished.

讨论分析了MIMO-OFDM中一种基于空频域的最优导频设置算法，给出了导频图案，通过仿真实验表明，该算法与理想的信道状态信息曲线非常接近，信噪比差距约在2dB左右，并且在快衰落条件下具有较好的稳定性，其性能要优于基于前导训练的信道估计方法。3、根据IEEE802.16OFDM系统特点，论文分别在Matlab中应用Simulink工具构建OFDM系统仿真平台、在LabVIEW平台上实现了OFDM调制解调仿真系统，模拟了整个系统的信号流程，进行了OFDM仿真系统参数的选择和调制模块的仿真设计、论证各算法性能，并根据各种不同的条件：例如高斯噪声、多径衰落、有无保护间隔等，对系统的误码特性进行了评估，为正确评价实际OFDM系统的性能提供了有效的理论依据。4、论文以软件无线电思想作为指导，提出了以256点IFFT／FFT为核心和以512点IFFT／FFT为核心的两种OFDM算法模式并存于同一个硬件平台、且可预选的方案，它们在参数选取和性能指标上有所差异，均实现了相似的模块和功能。5、论文参考IEEE 802.16无线网络标准的参数设置，针对本设计系统的应用环境和系统硬件的性能速率，提出了一种应用于实验室环境的信号结构、帧格式等参数设计。6、论文基于TI公司的6701evm数字评估板卡，结合模拟前端搭建数字中频平台，设计了基带处理的DSP软件模块并进行系统调试，基本实现了一套完整的OFDM调制解调方案。

This paper proposes a new multimedia transmission mechanism over wireless Internet. Based on the differences in bit error rate and transmission trip time between the wired and the wireless, error control and fading control in wireless Internet are improved....

提出了一种面向无线互联网的多媒体数据传输有效机制，根据有线和无线传输数据所存在的不同位误码率和传输时间响应等特点，改善了有线与无线相结合网络中多媒体传输的差错控制和衰减控制，实验结果证明了本机制的有效性。

Theoretical analysis and simulation results show that the both the DPSO-DA and the HDPSO-DA acquire about 3 dB and 5 dB gain over the OSIC algorithm based on the minimum mean square error criterion at a bit error rate of 10^(-3) and have lower computational complexity.

理论分析和仿真结果表明，当误码率为10^(-3)时，与基于最小均方误差准则的串行干扰抵消算法相比，DPSO-DA和HDPSO-DA可获得约3dB和5dB的增益，且具有更低的复杂度。

In order to decrease the measuring error of signal processing in laser Doppler velocimeter, frequency spectrum correction methods for lacer Doppler signal were proposed. Basic principles of energy centrobaric correction, ratio correction and phase difference correction were expounded. The three methods processing ideal sinusoidal signals was simulated with different signal frequencies, and so was the ratio method processing sinusoidal signals with different noises and signal to noise ratios.

在激光多普勒测速仪中，为了减小由信号处理算法带来的测量误差，提出运用频谱校正算法对多普勒信号的频谱进行校正，详细阐述了能量重心法、比值法和相位差法3种离散频谱校正算法的基本原理，运用这3种算法对理想正弦信号进行仿真，并运用比值法对信号施加不同频率和信噪比的噪音下的正弦信号和实测的多普勒信号进行仿真及实验研究。

The operation condition of a series-resonant converter is equivalently analyzed under open-loop condition. OCC condition and selection basis of resonant parameter and switching frequency are determined. The relationships between LED number, transformer turns ratio and constant current error are also determined, which provide scientific basis for the selection of LED number and transformer turns ratio.

文中通过对串联谐振变换器开环工作状态的等效分析，确定开环恒流条件和谐振参数与开关频率的选择依据，以及LED数目、变压器变比与恒流误差之间的关系，为LED数目及变压器变比的优化选择奠定了理论基础。

By comparing the error correction capability and stability under different signal-to-noise ratio conditions, and packet loss rate of the block code and the convolutional code in the same signal-to-noise ratio condition, the results show that correcting ability of this algorithm is better than that of other method under the low delay condition, and it can adapt the different network delay condition.

通过对比在不同的信噪比条件下卷积码的纠错能力和稳定性，以及在相同信噪比的情况下对分组码和卷积码的丢包率，说明本文算法的纠错能力在低解码延迟条件下好于现有方法，能适应不同的网络延迟条件。

These are places without aristocratic baggage; egalitarian places open to talent, self-improving, engaged in learning and innovation through networks that were at once competitive and cooperative.

这些地方没有贵族遗风作祟，而且对于那些有天分的人是开放的平等之地，这些人善于通过那些曾经很具有竞争力与合作精神的关系网进行自我提高以及学习创新。

Christine: You don't want to see me?

你不想见我？