import java.awt.Color;
import java.awt.Dimension;
import java.awt.Image;
final public class MultipathPPM extends MultiPathConvolution{
public MultipathPPM (Dimension dim, Image img, String problemName){
super(dim,img,problemName);
}
//==========================================
// Parameter initializations
//------------------------------------------
protected void initPreconstructor_Variables(){
initPreconstructorInMPLevel();
L=2;
Amax=1;
subModel=2;
tapsSimulationLimit=10000;
flgDrawNumbers=-1;
modelDescription[0]="Program2. Model: PPM with ISI, Noise, and Ambient Light. Graph: BER(SNR).";
modelDescription[2]=" ";
modelDescription[3]=" "+"Horizontal axis stands for SNR, db. "+
"Vertical axis stands for log(BER)/log(10).";
functionCOUNT=4;
functionTitle[0]="BER. SNR=2. Rb=100 MHz";
functionTitle[1]="BER,db. Rb=0.05 Mhz";
functionTitle[2]="BER,db. Rb=10 Mhz";
functionTitle[3]="BER,db. Rb=100 Mhz";
dmnRangeF=20.0;
dmnRangeFDown=19.0;
dmnRangeX=10.0;
grPoints=20;
drawGrid=true;
drawLengenOnCurve=false;
gridStepY=1.0;
grStartF=120;
functionColor=new Color[]{
new Color(150,0,0),
new Color(0,40,0),
new Color(150,0,150),
new Color(0,0,255),
new Color(255,0,0),
new Color(0,0,255)
};
}
//-----------------------------------------------
// User Input Prompts
//- - - - - - - - - - - - - - - - - - - - - - - -
protected int setParsToStrings(){
int i=0;
String decription="";
for(int j=0; j<subModelTitle.length; j++){
decription += ", "+j+" - " + subModelTitle[j];
}
strParsCrr[i][0]=String.valueOf(subModel); strParsCrr[i][1]="Sub Model: "+decription; strParsCrr[i++][2]="int";
strParsCrr[i][0]=String.valueOf(shotNoisePresented); strParsCrr[i][1]="shotNoisePresented, 0 or 1"; strParsCrr[i++][2]="int";
//strParsCrr[i][0]=String.valueOf(SNR); strParsCrr[i][1]="SNR, dB"; strParsCrr[i++][2]="double";
strParsCrr[i][0]=String.valueOf(amSAR); strParsCrr[i][1]="SAR, Signal to Ambient Light Ratio"; strParsCrr[i++][2]="double";
strParsCrr[i][0]=String.valueOf(amInterferencePeriodTi); strParsCrr[i][1]="Ti, Ambient Light Interference Period, sec"; strParsCrr[i++][2]="double";
strParsCrr[i][0]=String.valueOf(amInteferenceSummationPoints); strParsCrr[i][1]="NTi, Ambient Light Interf. Sum. Points Numb., 1 for no Interference."; strParsCrr[i++][2]="int";
strParsCrr[i][0]=String.valueOf(dmnRangeX); strParsCrr[i][1]="Argument Range"; strParsCrr[i++][2]="double";
strParsCrr[i][0]=String.valueOf(dmnRangeF); strParsCrr[i][1]="Function Range"; strParsCrr[i++][2]="double";
strParsCrr[i][0]=String.valueOf(dmnStartF); strParsCrr[i][1]="Function Start"; strParsCrr[i++][2]="double";
//strParsCrr[i][0]=String.valueOf(Rb); strParsCrr[i][1]="Bit Rate, Rb"; strParsCrr[i++][2]="double";
strParsCrr[i][0]=String.valueOf(ceilingHeight); strParsCrr[i][1]="Room Height, meters"; strParsCrr[i++][2]="double";
strParsCrr[i][0]=String.valueOf(L); strParsCrr[i][1]="Maximum symbol length, L"; strParsCrr[i++][2]="int";
strParsCrr[i][0]=String.valueOf(Amax); strParsCrr[i][1]="Non-zero levels in chip amplitude, A"; strParsCrr[i++][2]="int";
return i;
}
public String setParsFromStrings(){
int i=0;
try{
subModel =Integer.parseInt(strParsCrr[i][0]); i++;
shotNoisePresented =Integer.parseInt(strParsCrr[i][0]); i++;
//SNR =Double.parseDouble(strParsCrr[i][0]); i++;
amSAR =Double.parseDouble(strParsCrr[i][0]); i++;
amInterferencePeriodTi = Double.parseDouble(strParsCrr[i][0]); i++;
amInteferenceSummationPoints = Integer.parseInt(strParsCrr[i][0]); i++;
dmnRangeX =Double.parseDouble(strParsCrr[i][0]); i++;
dmnRangeF =Double.parseDouble(strParsCrr[i][0]); i++;
dmnStartF =Double.parseDouble(strParsCrr[i][0]); i++;
//Rb =Double.parseDouble(strParsCrr[i][0]); i++;
ceilingHeight =Double.parseDouble(strParsCrr[i][0]); i++;
L =Integer.parseInt(strParsCrr[i][0]); i++;
Amax =Integer.parseInt(strParsCrr[i][0]); i++;
}catch(Exception e){
return "Exception when (re)setting parameters.\n" + e;
}
return "";
}
//- - - - - - - - - - - - - - - - - - - - - - - -
// User Input Prompts
//================================================================
protected void spawnParametersAfterUserApplied(){
tapsSimulationLimit=10000;
simulationBlocked=false;
userImputCheckOrCorrectionBeforeBasic();
if(!simulationBlocked)spanParsInMPLevel();
if(!simulationBlocked)userImputCheckOrCorrectionAfterBasic();
if(!simulationBlocked)displySpawnedPars();
simulateThresholding();
if(simulationBlocked){
for(int i=20; i<modelDescription.length; i++){
modelDescription[i]=null;
}
//Set B to 1.0 to attract attention:
BAmb=1.0;
con("Simulation blocked.");
}
}
private void userImputCheckOrCorrectionBeforeBasic(){
for(int i=4; i<modelDescription.length; i++){
modelDescription[i]=null;
}
if(L<2){
modelDescription[10]="L must be > 1";
//Set B to 1.0 to attract attention:
simulationBlocked=true;
}
}
private void userImputCheckOrCorrectionAfterBasic(){
for(int i=20; i<modelDescription.length; i++){
modelDescription[i]=null;
}
if(tapsSimulationLimit<=tapsNumber){
modelDescription[20]="BER for sub Model " + subModelTitle[subModel]+". Taps Number exceeded limit.";
//Set B to 1.0 to attract attention:
simulationBlocked=true;
}
if(2!=subModel){
modelDescription[20]="Sub model " + subModelTitle[subModel]+
" requested, but only " + subModelTitle[subModel]+
" is implemented in this window.";
//Set B to 1.0 to attract attention:
simulationBlocked=true;
}
}
//---------------------------------------------------------
//To display this strings in graph background:
//- - - - - - - - - - - - - - - - - - - - - - - - - - - - -
private void displySpawnedPars(){
//con("subModelTile[0]="+subModelTitle[0]+" " + subModel);
modelDescription[1]="Sub Model = "+subModelTitle[subModel];
modelDescription[4]="A="+Amax;
modelDescription[5]="L="+L;
//modelDescription[6]="SNR="+SNR+",db SNR="+SN;
modelDescription[7]="Symbols in Alphabet="+aphabetCount;
modelDescription[8]="M="+M;
//modelDescription[9]="BitRate, Rb="+Rb+", bits/second.";
modelDescription[10]="Average Length="+avLength;
modelDescription[11]="Bits per chip="+bitsPerChip;
//modelDescription[12]="Chip Length="+T+", seconds.";
modelDescription[13]="Room Height="+ceilingHeight+", meters.";
modelDescription[14]="Dispersion Length Scale, a="+a+", seconds.";
modelDescription[15]="Lambda="+lambda;
modelDescription[16]="Recent tapsNumber="+tapsNumber;
}
//- - - - - - - - - - - - - - - - - - - - - - - - - - - - -
// To display this strings in graph background:
//------------------------------------------
// Parameter initializations
//==========================================
//==========================================
// Simulation
//------------------------------------------
final protected void simulateThresholding(){
if(simulationBlocked)return;
//First, find out number of slots of symbols which
//precede primary symbol and can interfere with primary symbol:
int sslots=0;
while(sslots*L<tapsNumber)sslots=sslots+1;
//Recalculated taps number which fits preceding symbols:
int pastTaps=sslots*L;
modelDescription[17]="RecentConvolving symbol slots number="+sslots;
//Recalculate tapsNumber including primary symbol:
int symTapsNumber=pastTaps+L;
modelDescription[18]="Recent preceding taps + L ="+symTapsNumber;
b=new int[symTapsNumber];
result=new double[symTapsNumber];
//Convolved primary symbol's ambient contribution for each chip:
double[] V=new double[L];
int symbol_events=1;
for(int i=0; i<sslots; i++){
symbol_events=symbol_events*L;
}
//Now, symbol_events=L^sslots
int PPMSymbolSimulationLimit=1000000;
//Protect against long calculations:
if(PPMSymbolSimulationLimit<=symbol_events){
modelDescription[20]="BER for sub Model " + subModelTitle[subModel]+
". Symbol Slots Limit exceeded.";
simulationBlocked=true;
return;
}
modelDescription[19]="Recent symbol events="+symbol_events;
//We are about ready to summarize ...
//Variance of J is squrt(2) times more than variance of N:
//UFun.setHMode(SN/Math.sqrt(2.0), 0==shotNoisePresented);
double SNR_PPM=SN/Math.sqrt(2.0);
boolean HeavisideMode=0==shotNoisePresented;
//Shortcuts:
double amK=1.0/amSAR; //Parameter K-declared in [7, Wong, ...]
double weight_ISI_NOISE=1.0/symbol_events/L/(L-1)/M;
BAmb=0.0; //Full BER
double amInterferenceStep=amInterferencePeriodTi/amInteferenceSummationPoints;
for(int iXAm=0; iXAm<amInteferenceSummationPoints; iXAm++){
double tt=amInterferenceStep*iXAm;
double BB=0.0; //BER under integration by time.
//Prepare ambient contributions to current symbol:
for(int i=0; i<L; i++){
V[i]=amK*am_vi(tt+T*i, T);
}
for(int e=0; e<symbol_events; e++){
//------------------------------------
//Generate symbols and chip sequences.
//- - - - - - - - - - - - - - - - - - -
int mask=symbol_events;
for(int slot=0; slot<sslots; slot++){
int sym=mask%L;
mask=(mask-sym)/L;
for(int i=0; i<L; i++){
b[slot*L+i]=0;
if(sym==i)b[slot*L+i]=Amax;
}
}
//- - - - - - - - - - - - - - - - - - -
//Generate symbols and chip sequences.
//------------------------------------
//Cycle through primary chips:
for(int i=0; i<L; i++){
//Fill primary symbol's chips with zeros:
for(int k=0; k<L; k++)b[sslots*L+k]=0;
//Fill one primary chip "with" non-zero amplitude:
b[sslots*L+i]=Amax;
//Calculate convolved chips from the top-1 to
//top-L-1 chip which are chips of current symbol:
convolve(pastTaps,b,result,false);
//con("e="+e);
//String debS="";
//for(int iii=0; iii<result.length; iii++){
// debS+=""+result[iii];
//}
//con("bh="+debS);
double Zi=lambda*result[pastTaps+i];
//con("Zi="+Zi);
if(amInteferenceSummationPoints>1)Zi=Zi+V[i];
//Cycle through competing chips:
for(int j=0; j<L; j++){
if(i==j)continue;
double Zj=lambda*result[pastTaps+j];
//con("Zj="+Zj);
if(amInteferenceSummationPoints>1)Zj=Zj+V[j];
double G=Zi-Zj;
//BB=BB+UFun.erfh(G);
BB=BB+UFun.erfh(G*SNR_PPM,HeavisideMode);
//con("Binstant="+BB+" G="+G);
}
}
//con("e="+e+" BB="+BB);
} //for(e
BAmb=BAmb+weight_ISI_NOISE*BB;
//con("iXAm="+iXAm+" BB="+BB+" BAmb="+BAmb);
} //for(int iXAm=0;
BAmb=BAmb/amInteferenceSummationPoints;
//do1 Wrong way. These values printed before calculations:
modelDescription[20]="Recent BER "+BAmb;
con("Recent BER "+BAmb);
}
//------------------------------------------
// Simulation
//==========================================
//Accuracy is restricted by 1e-16.
private double LogBERonSNR(double SNR, double Rb){
this.SNR=SNR;
this.Rb=Rb;
spawnParametersAfterUserApplied();
//simulateThresholding();
if(1.0e-16>BAmb)return -16.0; //Blind return. Assumed accuracy limit in Java.
return Math.log(BAmb)/Math.log(10);
}
//Accuracy is restricted by 1e-16.
private double BERonSNR(double SNR, double Rb){
this.SNR=SNR;
this.Rb=Rb;
spawnParametersAfterUserApplied();
//simulateThresholding();
if(1.0e-16>BAmb)return 1.0e-16; //Blind return. Assumed accuracy limit in Java.
return BAmb;
}
//UCFun ftest=new UCFun();
protected double functionSwitchX(int fIx, double t) {return 0;}
protected double functionSwitch(int fIx, double x){
switch(fIx){
case 1: return LogBERonSNR(x, 0.05E6);
case 2: return LogBERonSNR(x, 50.0E6);
case 3: return LogBERonSNR(x, 100.0E6);
case 0: return BERonSNR(2.0, 100.0E6);
}
return 0;
}
}
Copyright (C) 2009 Konstantin Kirillov