METHOD FOR RECEIVING PULSED OPTICAL SIGNALS Russian patent published in 2022 - IPC G01R19/175 H01L31/107 

FIELD: optical technology.

SUBSTANCE: invention relates to the reception of optical signals, in particular to the technique of receiving signals using avalanche photodiodes. A method for receiving pulsed optical signals using an avalanche photodiode, including threshold signal processing using a threshold device and the formation of output pulses, provides for pre-determining the non-multipliable component of the square of the noise current brought to the output of the photodiode, set the threshold $$$ brought to the output of the photodiode, within where is the square of the non-multipliable noise current brought to the output of the photodiode, setting the offset voltage of the photodiode at the level at which the avalanche multiplication coefficient $$$ where α is the noise coefficient of the photodiode, the square of the multiplied component of the primary noise current brought to the output of the photodiode; e is the electron charge; I₁ is the primary multiplied dark current of the photodiode; Δf is the bandwidth of the receiving path, after that, the offset voltage is reduced until the frequency f_nM of noise emissions exceeding the threshold drops to the maximum permissible level, while the offset voltage is fixed and the threshold is reduced to a level at which the frequency of noise emissions exceeding the threshold does not reach the nominal intermediate value $$$ , then the threshold is increased $$$ times, where f₀ is the frequency of zero-level noise crossing, and fm is the maximum permissible frequency of false alarms in operating mode, after which the threshold is fixed and signals are received.

EFFECT: at maximum speed, sensitivity close to the maximum achievable is provided in all modes, including in the presence of microplasma breakdowns.

4 cl, 3 dwg

I_{пор0 –} I_thr0

М_{опт –} M_opt.

f_{шМ –} f_nM

_m