Wireless Networks And Mobile Computing

cdma.java

//coded by anuj_jha(170303105120)
//P2: CDMA for two user and one bit data.
import java.util.Scanner;
public class cdma {
    static Scanner input = new Scanner(System.in);
    public static void main(String[] ar){
        System.out.println("Enter Data 1 (1 bit) : ");
        int data1 = inputData();
        System.out.println("Enter code 1 (4 bit) : ");
        int[] codeArray1 = inputArray();
        System.out.println("Enter Data 2 (1 bit) : ");
        int data2 = inputData();
        System.out.println("Enter code 2 (4 bit) : ");
        int[] codeArray2 = inputArray();
        int[] sendingCode1=sendingCodeGenerator(codeArray1,data1);//multiply
        int[] sendingCode2=sendingCodeGenerator(codeArray2,data2);//multiply
        System.out.print("\nSending Code 1    :");
        printArray(sendingCode1);
        System.out.print("\nSending Code 2    :");
        printArray(sendingCode2);
        int[] channelCode=channelCodeGenerator(sendingCode1,sendingCode2);//add
        System.out.print("\nChannel Code      :");
        printArray(channelCode);
        //multiply
        int[] receivingCode1 = calculatedReceivingCode(codeArray1,channelCode);
        //multiply
        int[] receivingCode2 = calculatedReceivingCode(codeArray2,channelCode);
        System.out.print("\nReceiving Code 1  : ");
        printArray(receivingCode1);
        System.out.print("\nReceiving Code 2  : ");
        printArray(receivingCode2);
        int outputCode1 = sum(receivingCode1);//sum/4
        int outputCode2 = sum(receivingCode2);//sum/4
        System.out.println("\nData 1             :"+outputCode1);
        System.out.println("Data 2             :"+outputCode2);
    }
    static int inputData(){
        int data = input.nextInt();
        if(data == 0){
            data = -1;
        }
        return data;
    }
    static int[] inputArray(){
        int[] temp = new int[4];
        for(int i = 0; i < 4; i++){
            temp[i] = input.nextInt();
            if(temp[i]==0){
                temp[i] = -1;
            }
        }
        return temp;
    }
    static int[] sendingCodeGenerator(int[] code, int data){
        int[] temp = new int[4];
        for(int i = 0; i < 4; i++){
            temp[i] = data * code[i];
        }
        return temp;
    }
    static int[] channelCodeGenerator(int[] code1, int[] code2){
        int[] chCode = new int[4];
        for (int i = 0; i < 4; i++){
            chCode[i] = code1[i] + code2[i];
        }
        return chCode;
    }
    static int[] calculatedReceivingCode(int[] code, int[] channel){
        int[] tmp = new int[4];
        for(int i = 0; i < 4; i++){
            tmp[i] = code[i] * channel[i];
        }
        return tmp;
    }
    static int sum(int[] code){
        int sum = 0;
        for(int i = 0; i < 4; i++){
            sum = sum + code[i];
        }
        int res = sum / 4;
        if(res == 0){
            res = -1;
        }
        return res;
    }
    static void printArray(int[] code) {
        for (int i = 0; i < 4; i++) {
            System.out.print(code[i]+"\t");
        }
    }
}

cdmaMultipleUser.java

//coded by anuj_jha(170303105120)
//P2: CDMA for n user m bit data o bit code.
//please enter -1 in place of '_' i.e for no data.
import java.nio.channels.Channel;
import java.util.Scanner;
class DataCodeModulation{
    static Scanner input = new Scanner(System.in);
    int[] data,code,sendingCode,channelCode;
    DataCodeModulation(int u){
        data = dataArrGen(u);
        code = codeArrGen(u);
        sendingCode = sendingArrGen(data,code);
    }
    public int[] codeArrGen(int u){
        System.out.print("Enter code for user "+u+" : ");
        return inputValue();
    }
    public int[] dataArrGen(int u){
        System.out.print("Enter data for user "+u+" : ");
        return inputValue();
    }
    public int[] sendingArrGen(int[] data, int[] code){
        int sendingArrSize = (data.length)*(code.length);
        int[] arr = new int[sendingArrSize];
        int k = 0;
        for (int i = 0; i < data.length; i++) {
            for (int j = 0; j < code.length && k < sendingArrSize; j++) {
                arr[k++] = data[i] * code[j];
            }
        }
        return arr;
    }
//     methods to take input and return the inputted value in the form of array.
//      This Also Convert 1 -> 1, 0 -> -1, other -> 0.
    public int[] inputValue(){
        String[] val = input.nextLine().split(" ");
        int[] arr = new int[val.length];
        for(int i = 0; i < arr.length; i++){
            arr[i] = Integer.parseInt(val[i]);
            if(arr[i] == 0){
                arr[i] = -1;
            }
            else if(arr[i] == 1){
                arr[i] = 1;
            }
            else{
                arr[i] = 0;
            }
        }
        return arr;
    }

    public void showData(){
        for(int i:data) { System.out.print(" "+i+" ");}
    }
    public void showCode(){
        for(int i:code) { System.out.print(" "+i+" ");}
    }
    public void showSendingCode(){
        for(int i:sendingCode) { System.out.print(" "+i+" ");}
    }
    public void setChannelCode(int[]  channelCodeReceived){
        channelCode = channelCodeReceived;
    }
}

public class cdmaMultipleUser{
//    Takes code during demodulation.
    public static int[] inputCode(){
        Scanner input = new Scanner(System.in);
        String[] val = input.nextLine().split(" ");
        int[] arr = new int[val.length];
        for(int i = 0; i < arr.length; i++){
            arr[i] = Integer.parseInt(val[i]);
            if(arr[i] == 0){
                arr[i] = -1;
            }
        }
        return arr;
    }
    //    it generate the intermediateCode by multiplying code in each block of channelCode
    public static int[] intermediateCodeGen(int[] code, int[] channelCode){
        int[] arr = new int[channelCode.length];
        for(int i = 0,j = 0; i < channelCode.length ; i++){
            if( j == code.length){
                j = 0;
            }
                arr[i] = code[j++] * channelCode[i];
            }
        return arr;
    }
//        calculate sum(intermediateCode[start to end]) / divisor.
//        range : including start excluding end
    public static int calculateData(int start, int end,int blockSize, int[] intermediateCode){
        int val = 0;
        for(int i = start; i < end; i++){
            val += intermediateCode[i];
        }
        return (val/blockSize);
    }

    public static void main(String[] args){
        Scanner input = new Scanner(System.in);
        int numberOfUser;
        System.out.print("How many Users : ");
        numberOfUser = input.nextInt();
//        This create number of object for $(numberOfUser) users of DataCode type.
//        ----------------------------------------------
        DataCodeModulation[] user = new DataCodeModulation[numberOfUser];
        for(int i = 0; i < numberOfUser; i++){
            DataCodeModulation obj = new DataCodeModulation(i);
            user[i] = obj;//name of obj like user[0], user[1]....
        }
//        ------------------------------------------------
        for(int i = 0; i < numberOfUser; i++) {
            System.out.print("\nData for User " + i + ": ");
            user[i].showData();
            System.out.print("\nCode for User " + i + ": " );
            user[i].showCode();
            System.out.print("\nSending_Code for User " + i + ": ");
            user[i].showSendingCode();
        }
        int size = (user[0].sendingCode).length;//get the size of the array for receiving code as all have same length so we
        int[] channelCode = new int[size];
        for(int i = 0; i < size; i++ ){
            for(int j = 0; j < numberOfUser; j++ ) {
                channelCode[i] += user[j].sendingCode[i];
            }
        }
//        this set the channelCode[] for each of user in DataCode class.
        for (int i = 0; i <  numberOfUser; i++){
            user[i].setChannelCode(channelCode);
        }
        System.out.print("\nChannel_Code : ");
        for(int i = 0; i < size; i++){
            System.out.print(" "+channelCode[i]+" ");
        }

        //demodulation menu
        while(true){
            System.out.print("\n\n###########################################\n");
            System.out.print("\n########### Demodulation Wizard ###########\n");
            System.out.print("\n###########################################\n");
            System.out.print("\nEnter your Code : ");
            int[] code = inputCode();
            int[] intermediateCode  = intermediateCodeGen(code,channelCode);
            int blockSize = code.length;
            int numOfBlock = channelCode.length/blockSize;
            int[] data = new int[numOfBlock];
            for (int i = 0; i < numOfBlock; i++){
                int start =  i * blockSize;
                int end = (i + 1) * blockSize;
                data[i]= calculateData(start,end,blockSize,intermediateCode);//range : including start excluding end
            }
            System.out.print("\nYour Data : ");
            for(int i = 0; i < numOfBlock; i++){
                if(data[i] == 0){
                    System.out.print(" _ ");
                }
                else if(data[i] == -1){
                    System.out.print(" 0 ");
                }
                else if(data[i] == 1){
                    System.out.print(" 1 ");
                }
            }
//            System.out.print(data[0]);//***************remove

//        at end ask user to continue or exit
            System.out.print("\n\n1.Continue");
            System.out.print("\n2.Exit");
            System.out.print("\n\nEnter Choice : ");
            int ch = input.nextInt();
            if(ch == 2){
                break;
            }
        }
    }
}

Perfect!