APD's excess noise measurements using spectral analysis (FFT)

Spectral Analysis using the FFT

To begin this discussion on spectral analysis, let us begin by considering the question of trying to detect an underlying sinusoidal signal component that is buried in noise. Such problems occur, for example, very commonly in the area of telecommunications. Suppose that such a signal-in-noise situation gives rise to the observed data record as shown in figure 1. Here the samples are collected a...

Exact Signal Measurements using FFT Analysis

This tutorial describes how to accurately measure signal power using the FFT. While it is easy to calculate powers in the time domain, this is not always applicable: If a signal contains several spectral components and broadband noise, considering the frequency domain allows to measure power of these components individually or to measure SNR (by separately considering signal and noise). However...

A simple empirical model for calculating gain and excess noise in GaAs/AlξGa1-ξAs APDs (0.3≤ξ≤0.6)

In this paper, we present a simple empirical model for calculating gain and excess noise in heterojunction GaAs/AlξGa1−ξAs APDs (0.3 ≤ ξ ≤ 0.6), without going through the relatively complicated and time consuming Monte Carlo simulation, commonly used for such devices. In this model, we present a set of empirical formula which can predict a distribution function for ionization path length for a ...

Analysis and Circuit Modeling of APDs

In this paper a new method for increasing the speed of SAGCM-APD is proposed. Utilizing carrier rate equations in different regions of the structure, a circuit model for the structure is obtained. In this research, in addition to frequency response, the effect of added new charge layer on some transient parameters like slew-rate, rising and falling times have been considered. Finally, by tradin...

Analysis Window Fft Speech Input Noise Spectrum Estimate