ID 原文 译文
23275 针对其调制参数估计，现有的方法大多基于小波变换，但其存在抗噪性能差，参数不易选取等问题。 For the issues of its modulation parameters' estimation, wavelet transform theory is mostly adopted in current algorithms. However, the anti-noise performance is poor and parameters are difficult to choose.
23276 通过对语图不确定原理的研究，该文提出一种语图逻辑“与”运算方法，并引入波形变换理论改善时频变换波形占空比，提高了估计算法的信噪比门限，完成低信噪比下 MFSK 信号调制参数的自适应盲估计。 On the research of indeterminacy theory of spectrogram, a strategy for spectrograms modifying is proposed and the waveform transforming theory is drawn into to upgrade the duty cycle. As the result, the anti-noise performance is improved and the self adaption blind parameter estimation is achieved.
23277 仿真表明，所提算法在抗噪声、频偏性能及参数选取鲁棒性上均优于现有常用算法，适合工程实践。 The simulation results indicate a better performance of proposed algorithm than current algorithms in anti-noise and frequency offset performance and robustness of parameters which makes it a better choice for engineering practice.
23278 该文针对太阳同步轨道卫星由于通讯误码导致卫星时钟不正常翻转造成的错误，提出了纠错策略。 Under the condition of working in sun-synchronous orbit, the error correction strategy is put forward due to the error caused by the communication error.
23279 基于卫星时钟和本地时钟授时误差互补的特点，设计了一种应用于低频输入信号和大倍频系数条件下的数字锁相环(DPLL)，利用数字锁相环使本地时钟跟踪卫星时钟秒脉冲的相位波动，实时消除本地时钟的累积误差。 According to the complementary error characteristics between satellite clock and local clock, a Digital Phase Locked Loop (DPLL) is designed, which is applied to the low frequency input signal and the large frequency multiplication factor. The local clock tracks the satellite clock pulse phase fluctuations and eliminates the accumulate error constantly.
23280 对该时钟源进行了理论分析和实验验证，用现场可编程门阵列(FPGA)予以实现。 The complete design is developed with Field Programmable Gate Array (FPGA) devices and the detailed theoretical analysis and experimental results are presented.
23281 实验表明，该设计实现的时钟源可以实时纠正卫星时钟出现的秒脉冲不正常翻转、秒脉冲丢失、时间包跳变、时间包丢失等错误，最短可以在 5 个输入时钟周期内进入锁定状态，稳定工作时每秒累积误差小于 100 μs，可作为星载光谱仪本地时钟源使用。 Experiments show that the design of the clock source can correct the abnormal flip or lose of second pulse and jump or lose of broadcast time package constantly. It can enter the lock state in 5 input clock cycles, and the cumulative error is less than 100 μs. It can be used as the local clock source of satellite borne equipment.
23282 电离层在地球同步轨道 SAR 长合成孔径时间内具有明显的时变特性，这使得传统的基于电离层总电子含量(TEC)固定值的校正方法不再适用。 The conventional correction method based on invariable TEC is no longer applicable to GEOSAR, because the temporal variability of ionosphere exits in synthetic aperture time of GEOSAR.
23283 为此，该文提出基于 4 维电子密度的地球同步轨道 SAR 成像补偿方法。 In this paper, a correction method based on 4-D electronic density is put forward.
23284 通过基于电离层实测数据的半物理仿真，对校正方法进行实验验证，结果表明该方法可以有效地校正电离层时变特性对地球同步轨道 SAR 成像质量的影响。 This method is validated using actual data of ionosphere and the results indicate that this method can correct the ionospheric effects induced by temporal variability on GEOSAR effectively.