High-speed parallel sampling method

Abstract

The invention discloses a high-speed parallel sampling method. The method comprises the following steps of S1, generating clock signals, and then obtaining a conversion clock signal and a data clock signal; S2, transmitting the conversion clock signal and the data clock signal to an ADC, and outputting digital signals to an FPGA module; S3, setting that each frame of sampling data comprises 20 bits, values of two bits with the highest bit are preset values, and the values of the bits with the other bit are practical sampling values; S4, judging whether the digital signals from the ADC module and the values in the first two bits of the sampling data of a data clock are the preset values or not, carrying out preset time of delay if the values in the first two bits are not the preset values,receiving the sampling data again until the values in the first two bits are the preset values, and sending the sampling data to an FIFO storage unit corresponding to the FPGA module after the frame of sampling data is received completely; S5, carrying out serial-to-parallel conversion on the sampling data; and S6, circulating the steps S1-S5, carrying out expansion to realize a 16-channel collection system, and finally realizing a 64-channel 18-bit 5MSPS collection system.

Description

Technical field [0001] The invention relates to the technical field of data sampling, in particular to a high-speed parallel sampling method. Background technique [0002] With the rapid development of terahertz technology, terahertz imaging has become more and more widely used. Compared with X imaging, terahertz imaging has the advantages of low emission power and no harm to the human body. At the same time, terahertz also has the characteristics of high bandwidth. , Maintains the advantages of X imaging such as high resolution and fine imaging, so it is more and more widely used in security inspection fields such as airports, high-speed railways, and public security systems. [0003] Terahertz imaging puts forward higher requirements for the acquisition system: because of the large bandwidth, the acquisition system is required to have a higher sampling rate; and because of the large dynamic range and high contrast required by imaging, the acquisition system is required to have hi...

AI Technical Summary

Problems solved by technology

[0004] As the core component of communication, radar and imaging systems, high-speed acquisition system has always been a hot spot and focus of research at home and abroad. Previous acquisition systems for communication and radar applications have a sampling accuracy of 14 to 16 bits and a sampling rate of 80 to 200 MSPS; For color Doppler ultrasound and other medical imaging systems, the ADC sampling accuracy is basically 12bit, and the sampling rate is >10MSPS; oscilloscopes and other measurement equipment require extremely high sampling rates (oscilloscopes with a bandwidth of 500M usually have a sampling rate exceeding 2.5GSPS), but the sampling accuracy is not high, usually Only need 8bit

[0005] High-precision acquisition system 18~24bit, usually in industrial measurement and other fields, such as scales, flowmeters, because a large dynamic range is required, usually requires 24bit resolution accuracy, but because the collected signal frequency is very low, usually below kHz, So the sampling speed of the ADC is not high (usually a few ksps to tens of ksps)

[0006] To sum up, it can be seen that for the acquisition system with a sampling accuracy of 18bit and a high sampling rate (5MSPS), there are not many researches due to fewer application fields.

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