数据采集外文翻译

数据采集外文翻译内容摘要：

ue input channel, each channel can output 16 the digital quantity. Six channel simultaneous sampling, and conversion, timeshare transmission, effectively reduce generated due to the sampling time different phase error. SY 5402EVM onboard DSP chip is TI pany39。 s 16 fixedpoint digital signal processor TMS320VC5402. It has high costperformance and provide highspeed, bidirectional, multichannel belt cushion, be used to serial port with system of other serial devices directly interface. The realization method of ac sample： In the field of power quality analysis,The fast Fourier transform (FFT) algorithm analysis of electric system harmonic is monly the FFT algorithm to signal a strict requirements synchronous sampling. The synchronous sampling influence: it39。 s difficult to acplish synchronous sampling and integer a period truncation in the actual measurement, so there was a affect the measurement accuracy of the frequency spectrum leakage problem. The signal has to deal with through sampling and A/D conversion get limited long digital sequence,the original signal multiplied by A rectangular window to truncated. Timedomain truncation will cause the detuning frequency domain, spectrum leakage occurs. In the synchronous sampling, because the actual signal every harmonic ponent can39。 t exactly landed in frequency resolution point in, but fall between the frequency resolution points. But FFT spectrum is discrete, only in all sampling points, while in other places of spectrum is not. Such through FFT and cannot directly get every harmonic ponent, but only the accurate value in neighboring frequency resolution point value to approximate instead of, can cause the fence effect realization method of synchronous sampling signal： According to provide different ways of sampling signal, synchronous sampling method and divided into software synchronous sampling method and hardware sy。