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Esiur Project 2022-11-26 17:03:52 +03:00
parent 68d0ca1873
commit 9775b2a878
2 changed files with 57 additions and 1 deletions
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4
Esiur.Analysis.Test/Program.cs
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@ -1,5 +1,6 @@
using System.Diagnostics;
using Esiur.Analysis.DSP;
using Esiur.Analysis.Signals.Codes;
namespace Esiur.Analysis.Test
{
@ -18,6 +19,9 @@ namespace Esiur.Analysis.Test
var cor = signalA.CrossCorrelation(signalB, true);
Debug.WriteLine(cor);
var seq = Generators.GenerateSequence(1, 7);
// To customize application configuration such as set high DPI settings or default font,
// see https://aka.ms/applicationconfiguration.
ApplicationConfiguration.Initialize();

54
Esiur.Analysis/Signals/Codes/Generators.cs
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@ -1,6 +1,7 @@
using Esiur.Data;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace Esiur.Analysis.Signals.Codes
@ -8,6 +9,57 @@ namespace Esiur.Analysis.Signals.Codes
public static class Generators
{
public static void SetBit(ref this int target, int index, bool value)
{
if (value)
target |= 0x1 << index;
else if ((target & (0x1 << index)) != 0)
target ^= 0x1 << index;
}
public static double[] GenerateSequence(int initialValue, uint octalPolynomialCoefficients)
{
// convert octal to uint
var bits = Convert.ToUInt32(octalPolynomialCoefficients.ToString(), 8);
var taps = new List<uint>();
// find maximum exponent
var maxExponent = 0;
for (var i = 31; i >= 0; i--)
{
var test = (uint)0x1 << i;
if ((bits & test) != 0)
{
taps.Add(test);
maxExponent = i;
break;
}
}
var length = (int)(Math.Pow(2, maxExponent) - 1);
var rt = new double[length];
var state = initialValue;
for(var i = 0; i < length; i++)
{
//rt[i] = (state & 0x1) == 1 ? 1 : -1;
var b = 0;
for (var j = 0; j < taps.Count; j++)
b = (b + ((taps[j] & state) > 0 ? 1 : 0)) % 2;
state >>= 1;
state.SetBit(maxExponent, b > 0);
rt[i] = b == 0 ? -1 : 1;
}
return rt;
}
//public double[][] GenerateMaximumLengthSequence(uint octalPolynomialCoefficients)
//{
// // convert octal to uint
@ -38,7 +90,7 @@ namespace Esiur.Analysis.Signals.Codes
// while (true)
// {
// }
// var rt = new double[length][];