duobinary cleanup (currently it is a mess)

Classes/01_transmit/PAMmapper.m

@@ -462,10 +462,19 @@ classdef PAMmapper
 
         end
 
-        function [Signal_out] = quantize(obj,Signal_in)
+        function [Signal_out] = quantize(obj,Signal_in,options)
+            arguments
+                obj 
+                Signal_in 
+                options.custom_const = []
+            end
 
-            constellation = obj.get_levels();
-            constellation = constellation ./ obj.scaling;
+            if isempty(options.custom_const)
+                constellation = obj.get_levels();
+                constellation = constellation ./ obj.scaling;
+            else
+                constellation = options.custom_const;
+            end
 
             issignalclass = 0;
             if isa(Signal_in,'Signal')