A method for extracting APD digital avalanche signal based on synchronous correlation sampling

Abstract

A synchronous correlated sampling APD digitized avalanche signal extraction method, through the high-speed analog-to-digital converter (ADC) to directly sample the two peak noises before and after, and perform digital difference operation on the sampled values ​​of the two periods before and after, to obtain the relevant sampled digital value, and then Through the delay scanning, find the delay time at which the digital value fluctuates the most, that is, the location where the avalanche signal occurs. By performing relevant sampling under the above delay, if the relevant sampling digital value exceeds the set digital threshold, it will be regarded as an effective Avalanche signal output. Compared with the prior art, the present invention can automatically offset the spike noise by means of correlation sampling and time-delay scanning, not only can directly extract the avalanche signal, but also can offset the APD output signal changes caused by environmental temperature drift and gating changes, Improve the gating frequency conversion capability of APD, so that the extraction of avalanche signals is stable and reliable, the detection efficiency remains stable, and there is no need for repeated calibration or calibration, which is simple, efficient and stable.

Description

Technical field[0001]The present invention relates to a single photon detector applied to the quantum communication, and can also be applied to the case of using the door control mode based on the APD, belonging to the field of single photome level infrared light strobe (G01J) and for quantum secure communication. The core detector technology field (H04K), particularly related to a synchronous correlation of APD digital avalanche signal extraction method.Background technique[0002]Near infrared single photon detection can use an IngaAs / INP avalanche diode (APD) working in the door control mode to achieve efficient single photon detection. However, the APD avalanche signal in the door-controlled mode of operation is difficult to extract abnormalities. Because the gardened signal is large, a large spike noise signal will be generated through the APD diode tape capacitance, how to extract avalanche signal, existing technology given Conventional approach: For example, a delayed method ...

AI Technical Summary

Problems solved by technology

[0007] The purpose of the present invention is to provide a synchronous correlated sampling APD digital avalanche signal extraction method to solve the existing avalanche signal extraction technology: not only can not achieve the optimal APD dark count and post-pulse performance, but also when the ambient temperature, gating characteristics (such as amplitude, width, frequency, etc.) changes, and repeated calibration is required, which is inconvenient to use, unstable in performance, and has technical defects such as temperature drift and failure risks

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