Write a matlab function, MATLAB Programming

Write a MATLAB function called pgm which calculates the periodogram. The function inputs should be the length input vector x and its output should be the length N periodogram estimate Pxx. Generate a length N discrete random signal with the randn function and use the pgm to estimate the PSD for N = 128, 256, and 512. Inspect and comment upon the results. The theoretical autocorrelation function for this discrete Gaussian random signal equals σ2δ (i.e. there is zero similarity between the signal and a shifted version of it), where is the standard deviation of the random signal; for the above random signal (see help randn), is equal to 1. Therefore its true PSD is a constant, unity, for all frequencies. Such a signal is referred to as white noise because it has a constant spectrum independent of frequency, as an, albeit approximate, analogy with white light. The difference between this ideal PSD and those estimated with the datasets is due, in part, to their ?nite lengths. One method to improve these estimates is to apply frequency domain smoothing.

- Employ the ?lt?lt command within MATLAB to smooth the PSD estimates with a zero phase FIR ?lter with impulse response sequence 0.2*[1 1 1 1 1]. Does this improve the apparent PSD estimate?

- Generate a length 1024 discrete random signal with the randn function and sub-divide the signal into eight separate 128 point signals. Estimate the PSD for each length 128 signal and display on two plots the eight results (Note: Break each window into 2× 2 sections. Read help ?gure on how to obtain the second window). Notice the variation of the estimates.

- These eight results can be averaged to yield a new PSD estimator called the averaged periodogram which has less variation than the individual PSDs. Display this result.

Posted Date: 2/27/2013 6:02:08 AM | Location : United States







Related Discussions:- Write a matlab function, Assignment Help, Ask Question on Write a matlab function, Get Answer, Expert's Help, Write a matlab function Discussions

Write discussion on Write a matlab function
Your posts are moderated
Related Questions
Goal: Learn how to do statistics, sorting and curve fitting in Matlab. Put all of those ".m" files in a folder called yourname_lab7, and zip the folder and submit it on the class w


Discuss the frequency range / radiation angles at which the two models diverge, and relate this divergence to your understanding of the behaviour of a pistonic source. Compare t

how to find absolute value of a number

The Programming Concept: In most of the programming languages, random function returns a real number; therefore the real number would then have to be rounded to produce a rand


People arrive at a microscope exhibit at a rate of one every 8+/- 2 minutes. Only one person can see the exhibit at a time. It takes 5 +/- 2 minutes to see the exhibit. A person

The fundamental theorem of calculus states that the de?nite integral of a function may be found from the antiderivative of the function. However, for many functions, it is much eas

Rules for variable names: In addition, the variable names must always be mnemonic that means they should make some sense. For illustration, if the variable is storing the radi