White Noise : Simulation and Analysis using Matlab

Definition A random process (or signal for your visualization) with a constant power spectral density (PSD) function is a white noise process. Power Spectral Density Power Spectral Density function (PSD) shows how much power is contained in each of the spectral component. For example, for a sine wave of fixed frequency, the PSD plot will … Read more

Derive BPSK BER – optimum receiver in AWGN channel

Key focus: Derive BPSK BER (bit error rate) for optimum receiver in AWGN channel. Explained intuitively step by step. BPSK modulation is the simplest of all the M-PSK techniques. An insight into the derivation of error rate performance of an optimum BPSK receiver is essential as it serves as a stepping stone to understand the … Read more

Q function and Error functions : demystified

In simple words, The Q-function gives the probability that a random variable from a normal distribution will exceed a certain threshold value. The erf function gives the probability that a normally distributed variable will fall within a certain range. Q function Q functions are often encountered in the theoretical equations for Bit Error Rate (BER) … Read more

Random Variables, CDF and PDF

Random Variable: A random variable is a mapping from sample space $latex \Omega\$ to a set of real numbers. What does this mean ? Lets take the usual evergreen example of “flipping a coin”. In a “coin-flipping” experiment, the outcome is not known prior to the experiment, that is we cannot predict it with certainty … Read more