WIP

Classes/Photodiode.m

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+classdef Photodiode
+    %PGOTODIODE Summary of this class goes here
+    %   Detailed explanation goes here
+
+    properties
+        fsimu
+        responsivity
+        dark_current
+        temperature
+
+    end
+
+    methods
+        function obj = Photodiode(options)
+            %PHOTODIODE Construct an instance of this class
+            %   Detailed explanation goes here
+            arguments
+                options.fsimu
+                options.responsivity = 1;
+                options.dark_current = 0;
+                options.temperature = 20;
+            end
+
+            obj.fsimu = options.fsimu;
+            obj.responsivity = options.responsivity;
+            obj.dark_current = options.dark_current;
+            obj.temperature = options.temperature;
+
+        end
+
+        function yout = process(obj,xin)
+            %METHOD1 Summary of this method goes here
+            %   Detailed explanation goes here
+
+            k = Constant.Boltzmann;
+            T = obj.temperature + 273.15 ; %celsius + 273 = kelvin
+            R = 50; %resistance of phdiode (50ohm is typical value)
+
+            % Magnitude squared detection
+            yout = sum( abs(xin) .^2*obj.responsivity,1) ;
+
+            % Shot Noise
+            shot_noise = sqrt(k * obj.fsimu .* yout)   .* randn(1,size(yout,1));
+
+            yout = yout + shot_noise;
+
+            % Thermal Noise
+            therm_current_psd = (2 * k * T / R ) ; %squared
+
+            Bw = obj.fsimu; %is this correct? shouldnt it be the bandwidth of the actual component? e.g. 70GHz?
+            therm_noise_pow = therm_current_psd * 2 * Bw; %squared
+
+            therm_noise = sqrt(therm_noise_pow) .* randn(1,size(yout,1));
+
+            yout = yout + therm_noise;
+
+            % Dark Current
+            yout = yout + obj.dark_current ;
+
+        end
+    end
+end
+