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1.
This paper describes a time-to-digital converter (TDC) with $sim $1.2 ps resolution and $sim $327 $mu$s dynamic range suitable for laser range-finding application for example. The resolution of $sim $1.2 ps is achieved with interpolation based on a cyclic time domain successive approximation (CTDSA) method that resolves the time difference between two non-repetitive signals using binary search. The method utilizes a pair of digital-to-time converters (DTC), the propagation delay difference between which is implemented by digitally controlling the unit load capacitors of their delay cells, thus enabling sub-gate delay timing resolution. The rms single-shot precision, i.e., standard deviation $sigma $-value of the TDC is 3.2 ps, which is achieved by using an external integral nonlinearity look-up table (INL-LUT) for the interpolators. The power consumption is 33 mW at 100 MHz with a 3.3 V operating voltage. The prototypes were fabricated in a 0.35 $mu{hbox {m}}$ CMOS process.   相似文献   

2.
高精度、高速、体积小、低功耗的定时器为激光飞行时间测量应用的关键部件.在单一程式逻辑芯片上成功制作具备上述优点且内含自我校准电路的完整时间数码转换器,使用最近提出的"分支式传递延时(PD)链"作时间内插,对不足计时周期的时段作细分计量.实验证实线性度达0.23%,比传统"单线式"PD链提高10倍,且其线性不受温度与电压影响.单发分辨率为1.459 ns,多发统计分辨率大约0.7 ns.本文也提出了分辨率提高到0.1 ns的方法.  相似文献   

3.
Interpolative digital-to-analog converters generate an output that has only a few analog levels. They provide fine resolution by oscillating rapidly between these levels in such a manner that the average output represents the value of the applied code. Here we describe an improved method of interpolating that results in reduced noise in the signal band. A theory of the interpolation, confirmed by experiments, demonstrates that switching between only two levels at 1.3 mHz could provide 16 bit resolution for telephone signals.  相似文献   

4.
More precise information on the chemisty, dynamics, and energy budget of the middle atmosphere can be derived from globally and simultaneously measured concentration profiles of a substantial number of atmospheric trace gases. Such a data base can be obtained from infrared limb spectra which are recorded by spaceborne instruments. Fourier transform spectrometers are especially appropriate for such a task. In this paper are discussed characteristic features and performance parameters of a compact high-resolution (0.05 cm-1) rapid-scanning (1 s) interferometer for measurements in the 2 to 15-?m region. Technical data of a cryogenic version as well as of an uncooled satellite instrument are presented.  相似文献   

5.
提出了一种用于20bit ∑-△数模转换器中的内插滤波器的有效实现方法,内插滤波器的过采样率为128.该方法使用多级结构以降低滤波器系数的复杂度和有限字长效应.同时提出了基于系数混合基分解的多相半带滤波器的无乘法器实现方法,它降低了控制逻辑的复杂程度,并大大节省了芯片面积.芯片采用0.13μm CMOS工艺实现,整个插值滤波器面积小于0.63mm2.整个电路系统仅用简单的硬件单元实现,且结构规整,这有利于大规模集成电路制造,并可应用于高精度数据转换电路中.  相似文献   

6.
提出了一种用于20bit ∑-△数模转换器中的内插滤波器的有效实现方法,内插滤波器的过采样率为128.该方法使用多级结构以降低滤波器系数的复杂度和有限字长效应.同时提出了基于系数混合基分解的多相半带滤波器的无乘法器实现方法,它降低了控制逻辑的复杂程度,并大大节省了芯片面积.芯片采用0.13μm CMOS工艺实现,整个插值滤波器面积小于0.63mm2.整个电路系统仅用简单的硬件单元实现,且结构规整,这有利于大规模集成电路制造,并可应用于高精度数据转换电路中.  相似文献   

7.
The analog part of a high-resolution A/D converter has been integrated in a compatible CMOS-JFET technology. The circuit, which forms a pulse-density modulator (PDM), can be operated at sample rates up to 12 MHz and reaches a peak SNR of 84 dB over a baseband of 20 kHz. This corresponds to approximately 14-bit A/D resolution.  相似文献   

8.
《电子产品世界》2005,(2):67-69
引言 目前电池供电便携式电子产品需要高效的电源解决方案,以满足高度集成系统延长电池寿命,降低散热问题的要求.另一方面,对于一个或多个电池供电的宽输入电压范围来说,电源输出电压需要保持恒定.  相似文献   

9.
Dynamic element matching (DEM) is widely used in multibit digital–analog converters (DACs) to prevent mismatches among nominally identical components from introducing nonlinear distortion. It has long been used as a performance- enabling technique in delta-sigma data converters which require low-resolution but high-linearity DACs. More recently, segmented DEM architectures have made high-resolution Nyquist-rate DEM DACs practical. However, the previously published segmented DEM DAC designs have been ad hoc. Systematic techniques for synthesizing segmented DEM DACs and analyses of their design tradeoffs have not been published previously. This paper quantifies a fundamental power dissipation versus complexity tradeoff implied by segmentation and provides a systematic method of synthesizing segmented DEM DACs that are optimal in terms of the tradeoff.   相似文献   

10.
综合利用到达方位角(DOA)和到达时间差(TDOA)等信息,建立单站无源定位系统的状态模型和观测模型,应用多维情形的二阶插值公式构造新型非线性滤波算法,而不需计算非线性函数的偏导,使得计算简化。仿真结果表明,用该算法可替代扩展卡尔曼滤波器(EKF)应用于单站无源定位中,能获得更为准确且收敛更快的定位结果。  相似文献   

11.
A proposed instrument for deployment on next-generation Geostationary Operational Environmental Satellite (GOES) platforms is the Geostationary Synthetic Thinned Aperture Radiometer (GeoSTAR). A high-resolution full-Earth disk model has been developed to aid in the design of the instrument and to characterize sensor performance. A number of ancillary geophysical data fields are used as inputs into a radiative-transfer model that also accounts for the propagation and viewing geometries from a geostationary Earth orbit (GEO). The model produces high-resolution (10 km times 10 km) simulated full-Earth disk microwave images from GEO. The model is used as a tool to examine several critical aspects of GeoSTAR performance and design. Differential image processing is assessed as a means of mitigating the effects of the Gibbs phenomenon; its performance is found to be excellent, even with nonideal a priori information. The spatial resolution and precision of images generated at 50 GHz are evaluated. The magnitude of the highest spatial-frequency components sampled by GeoSTAR is found to be well above its minimum detectable signal. However, the differential image processing removes most of the high-frequency content, which is due to static high-contrast boundaries in the scene. Most of the residual high-frequency content lies at or below the instrument noise floor.  相似文献   

12.
This paper describes an interconnect technique for subthreshold circuits to improve global wire delay and reduce the delay variation due to process-voltage-temperature (PVT) fluctuations. By internally boosting the gate voltage of the driver transistors, operating region is shifted from subthreshold region to super-threshold region enhancing performance and improving tolerance to PVT variations. Simulations of a clock distribution network using the proposed driver shows a 66%-76% reduction in 3sigma clock skew value and 84%-88% reduction in clock tree delay compared to using conventional drivers. A 0.4-V test chip has been fabricated in a 0.18-mum 6-metal CMOS process to demonstrate the effectiveness of the proposed scheme. Measurement results show 2.6times faster switching speed and 2.4times less delay sensitivity under temperature variations.  相似文献   

13.
改变图像尺寸是多速率系统的重要应用之一。提出了一种通过采样率转换改变图像尺寸的有效方法,给出了线性相位FIR插值滤波器和线性相位FIR抗混叠滤波器的设计算法。结合实例说明了方法的有效性。  相似文献   

14.
A two-step high-precision Time-to-Digital Converter(TDC), integrated with a Single-Photon Avalanche Diode(SPAD), used for Time-Of-Flight(TOF) application, has been developed and tested. Time interval measurement is performed by the coarse counter and fine interpolator, which are utilized to measure the total periods and the residue time of the reference clock, respectively. Following a detail analysis of time precision and clock jitter in the two-step structure, the prototype TDC fabricated in GSMC 1P6M 0.18 μm CMOS Image Sensor(CIS) technology exhibits a Single-Shot Precision(SSP) of 11.415 ps and a dynamic range of 216.7 ns. In addition, a pixel of the chip occupies 100 μm×100 μm, and the measured Integral Nonlinearity(INL) and Differential Nonlinearity(DNL) are better than ±0.88 LSB and ±0.67 LSB, respectively. Meanwhile, the overall power consumption of the chip is 35 mW at 1.8 V power supply. Combined with these characteristics, the designed chip is suitable for TOF-based ranging applications.  相似文献   

15.
本文报导一种创新的“环状传递延时式”单芯片时间数码转换器,由于线性度优异,测量“预时段”极短,故适用于高重复率光学飞时测距应用,例如扫瞄式三维测量激光雷达。使用一种简单的电路让循环脉冲第一周均回复其脉宽,使可转换的时间长度不会如以往装置因脉冲之前沿与后沿前进速度不同而受到限制。使用讥售可编程逻辑片所制造之原型样机。实验测得「之微分误差小于115psec,非线笥度小于0.31%,而最长可测时间只受限  相似文献   

16.
对于大区域空间直角坐标之间的相互转换,文章提出采用多项式拟合的方法进行转换,并以80坐标转换到 2000坐标为例,说明对于大区域空间直角坐标数据间的转换,采用二次、三次多项式拟合的方法是有效的,为 大区域坐标转换提供了新的转换思路。  相似文献   

17.
当目标为宽带信号时,现有单站无源定位方法需要的参数难以获取。而时差和时差变化率是一种宽窄带都适用的观测量。因此,在分析时差和时差变化率所包含目标信息的基础上,建立了一种新的单站对宽带信号源的定位模型,并利用粒子滤波算法对该模型进行滤波处理。仿真实验表明了该方法的有效性。  相似文献   

18.
无源时差定位系统的静止目标聚类检测算法   总被引:3,自引:0,他引:3  
利用时差定位系统的定位误差特性,基于蚁群优化算法,提出了一种蚁群聚类检测算法,在不需要先验信息的情况下,实现了对静止目标的检测。实际数据测试结果表明蚁群聚类检测算法能够有效检测静止目标并估计目标位置,系统对静止目标的定位精度得到了显著改善。  相似文献   

19.
In this paper a fully monolithic on-chip local oscillator signal generation circuit is presented for eliminating the negative effect of coupling between bond-wires, package pins and output and input lines of the power amplifier output to the local oscillator input for direct conversion transmitters. The proposed circuit generates the local oscillator signal at frequencies 1710–1785 GHz which is harmonically uncorrelated from two input signals at 464 MHz and 1792–2088 MHz. The required building blocks are a frequency divider, a mixer and an active band-pass filter. Fully monolithic high frequency band-pass filters have not been available until recently, and the designed circuit is in fact one of the first applications reported for MMIC active filters in cellular phones. The circuit is designed with a 0.5 m GaAs MESFET technology and the performance is verified with on-chip measurements.  相似文献   

20.
较详细介绍了一种基于三站时差定位体制的无源探测与跟踪雷达系统时差接收机的设计,该方案采用了信道化接收技术和混合门限信号检测方法  相似文献   

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