High-precision use method of low-resolution AD converter and optical time domain reflectometer thereof

Abstract

The invention discloses a high-precision use method of a low-resolution AD converter and an optical time domain reflectometer thereof, and the method comprises the steps: introducing an analog output branch, which comprises the steps: building an analog signal source, enabling the quantization step size of the analog signal source to be smaller than the quantization step size of the acquisition AD converter, and enabling the output full scale amplitude to be larger than the quantization step size of the acquisition AD converter; addition introduction: setting an adder, adding the output of the analog output branch and the output of the original detection path through the adder, and then outputting to an AD converter for acquisition; detection execution: recording the quantization step length of the analog output branch as V; the original detection path performs primary signal detection, and the output of the analog output branch is increased by V; and signal restoration: after multiple times of acquisition, averaging all acquisition curves through accumulation, and subtracting a known bias voltage mean value to obtain a real curve. The present application has the effect of achieving the measurement accuracy of a high-order AD converter with a low-resolution AD converter.

Description

technical field [0001] The present application relates to an optical time domain reflectometer, in particular to a high-precision use method of a low-resolution AD converter and an optical time domain reflectometer thereof. Background technique [0002] The resolution of the AD converter is defined as the full-scale voltage vs. ratio of is the number of bits of the AD converter. When the input analog is at and When changing between, the conversion result is ; When input analog and When changing between, the conversion result is ; When the analog input is in and When changing between, the conversion result is . [0003] According to the above, it can be seen that this is As a unit to quantify the input analog quantity, that is Indicates the quantization step size of the AD converter. It can be known from the quantified results that when the analog quantity change is Between them, it is no longer possible to make a finer resolution, which causes ...

AI Technical Summary

Problems solved by technology

[0008] However, the unit price of 12-bit, 14-bit and above D converter chips is generally more expensive, and they basically rely on imports. Especially for high-speed AD converters above 14 bits, domestic chips are even rarer, resulting in an increase in the cost of related equipment. The development of the industry is limited, so this application proposes a new technical solution

Images