#include using namespace itpp; //These lines are needed for use of cout and endl using std::cout; using std::endl; int main() { //Declarations of scalars and vectors: int i, Number_of_bits; double Ec, Eb; vec EbN0dB, EbN0, N0, noise_variance, bit_error_rate; //vec is a vector containing double bvec transmitted_bits, received_bits; //bvec is a vector containing bits cvec transmitted_symbols, received_symbols; //cvec is a vector containing double_complex //Declarations of classes: QPSK qpsk; //The QPSK modulator class AWGN_Channel awgn_channel; //The AWGN channel class it_file ff; //For saving the results to file BERC berc; //Used to count the bit errors Real_Timer tt; //The timer used to measure the execution time //Reset and start the timer: tt.tic(); //Init: Ec = 1.0; //The transmitted energy per QPSK symbol is 1. Eb = Ec / 2.0; //The transmitted energy per bit is 0.5. EbN0dB = linspace(0.0,9.0,10); //Simulate for 10 Eb/N0 values from 0 to 9 dB. EbN0 = inv_dB(EbN0dB); //Calculate Eb/N0 in a linear scale instead of dB. N0 = Eb * pow(EbN0,-1.0); //N0 is the variance of the (complex valued) noise. Number_of_bits = 100000; //One hundred thousand bits is transmitted for each Eb/N0 value //Allocate storage space for the result vector. //The "false" argument means "Do not copy the old content of the vector to the new storage area." bit_error_rate.set_size(EbN0dB.length(),false); //Randomize the random number generators in it++: RNG_randomize(); //Iterate over all EbN0dB values: for (i=0; i //Show how the simulation progresses: cout //Generate a vector of random bits to transmit: transmitted_bits = randb(Number_of_bits); //Modulate the bits to QPSK symbols: transmitted_symbols = qpsk.modulate_bits(transmitted_bits); //Set the noise variance of the AWGN channel: awgn_channel.set_noise(N0(i)); //Run the transmited symbols through the channel using the () operator: received_symbols = awgn_channel(transmitted_symbols); //Demodulate the received QPSK symbols into received bits: received_bits = qpsk.demodulate_bits(received_symbols); //Calculate the bit error rate: berc.clear(); //Clear the bit error rate counter berc.count(transmitted_bits,received_bits); //Count the bit errors bit_error_rate(i) = berc.get_errorrate(); //Save the estimated BER in the result vector } tt.toc(); //Print the results: cout cout cout cout cout //Save the results to file: ff.open("qpsk_result_file.it"); ff ff ff.close(); //Exit program: return 0; }
