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Create data arrays

The code in Listing 10 creates the array objects that will be used to store the data until it is retrieved by the methods named f1 through f5 .

Listing 10. Create data arrays.
double[] data = new double[dataLen]; double[]operator = new double[operatorLen]; double[]output = new double[outputLen]; double[]spectrumA = new double[spectrumPts]; double[]spectrumB = new double[spectrumPts];

Beginning of the constructor

Most of the hard work is done by the constructor or by methods called by the constructor.

The code in Listing 11 shows the beginning of the constructor for the class. This code generates and saves the white noise in the array object named data .

Listing 11. Beginning of the constructor.
public Dsp002(){//constructor Random generator = new Random(new Date().getTime()); for(int cnt=0;cnt<data.length; cnt++){//Get data, scale it, remove the // dc offset, and save it.data[cnt] = 100*generator.nextDouble()-50; }//end for loop

The random noise generator seed

Note that by virtue of the way this white noise is being generated, a different seed is passed to the constructor for the Random class each time an object of the Dsp002 class is instantiated. Thus, each new object presents different random noise.

(In some cases, this may not be desirable and it may be preferable to use the same seed each time an object is instantiated.)

Create the convolution operator

The code in Listing 12 creates the 33-point convolution operator, as a segment of a cosine wave, and saves it in the designated array.

Listing 12. Create the convolution operator.
for(int cnt = 0; cnt<operatorLen; cnt++){operator[cnt] = Math.cos(cnt*2*Math.PI/4); }//end for loop

Note that the constant value of 4 in the denominator of the argument to the cos method specifies the frequency of the cosine wave relative to the sampling frequency. (In this case, the frequency of the cosine wave is one-fourth the sampling frequency.)

Apply the convolution operator

The code in Listing 13 calls a static method named convolve in a class named Convolve01 to apply the convolution operator to the white noise and save the filtered result in the appropriate array. I will briefly discuss this methodlater.

Listing 13. Apply the convolution operator.
Convolve01.convolve(data,dataLen, operator,operatorLen,output);

Compute spectrum of each of two traces

The code in Listing 14 calls a static method named dft of a class named Dft01 twice in succession to compute the spectra for the white noise and the filterednoise, and to save those spectra in the appropriate arrays.

Listing 14. Compute spectrum of each of two traces.
Dft01.dft(data,spectrumPts, spectrumA);Dft01.dft(output,spectrumPts, spectrumB);}//end constructor

All results have been computed and saved

That is the end of the constructor. At this point, all the results have been computed and saved in the appropriate arrays for later retrieval by the methodsnamed f1 through f5 .

Questions & Answers

Three charges q_{1}=+3\mu C, q_{2}=+6\mu C and q_{3}=+8\mu C are located at (2,0)m (0,0)m and (0,3) coordinates respectively. Find the magnitude and direction acted upon q_{2} by the two other charges.Draw the correct graphical illustration of the problem above showing the direction of all forces.
Kate Reply
To solve this problem, we need to first find the net force acting on charge q_{2}. The magnitude of the force exerted by q_{1} on q_{2} is given by F=\frac{kq_{1}q_{2}}{r^{2}} where k is the Coulomb constant, q_{1} and q_{2} are the charges of the particles, and r is the distance between them.
Muhammed
What is the direction and net electric force on q_{1}= 5µC located at (0,4)r due to charges q_{2}=7mu located at (0,0)m and q_{3}=3\mu C located at (4,0)m?
Kate Reply
what is the change in momentum of a body?
Eunice Reply
what is a capacitor?
Raymond Reply
Capacitor is a separation of opposite charges using an insulator of very small dimension between them. Capacitor is used for allowing an AC (alternating current) to pass while a DC (direct current) is blocked.
Gautam
A motor travelling at 72km/m on sighting a stop sign applying the breaks such that under constant deaccelerate in the meters of 50 metres what is the magnitude of the accelerate
Maria Reply
please solve
Sharon
8m/s²
Aishat
What is Thermodynamics
Muordit
velocity can be 72 km/h in question. 72 km/h=20 m/s, v^2=2.a.x , 20^2=2.a.50, a=4 m/s^2.
Mehmet
A boat travels due east at a speed of 40meter per seconds across a river flowing due south at 30meter per seconds. what is the resultant speed of the boat
Saheed Reply
50 m/s due south east
Someone
which has a higher temperature, 1cup of boiling water or 1teapot of boiling water which can transfer more heat 1cup of boiling water or 1 teapot of boiling water explain your . answer
Ramon Reply
I believe temperature being an intensive property does not change for any amount of boiling water whereas heat being an extensive property changes with amount/size of the system.
Someone
Scratch that
Someone
temperature for any amount of water to boil at ntp is 100⁰C (it is a state function and and intensive property) and it depends both will give same amount of heat because the surface available for heat transfer is greater in case of the kettle as well as the heat stored in it but if you talk.....
Someone
about the amount of heat stored in the system then in that case since the mass of water in the kettle is greater so more energy is required to raise the temperature b/c more molecules of water are present in the kettle
Someone
definitely of physics
Haryormhidey Reply
how many start and codon
Esrael Reply
what is field
Felix Reply
physics, biology and chemistry this is my Field
ALIYU
field is a region of space under the influence of some physical properties
Collete
what is ogarnic chemistry
WISDOM Reply
determine the slope giving that 3y+ 2x-14=0
WISDOM
Another formula for Acceleration
Belty Reply
a=v/t. a=f/m a
IHUMA
innocent
Adah
pratica A on solution of hydro chloric acid,B is a solution containing 0.5000 mole ofsodium chlorid per dm³,put A in the burret and titrate 20.00 or 25.00cm³ portion of B using melting orange as the indicator. record the deside of your burret tabulate the burret reading and calculate the average volume of acid used?
Nassze Reply
how do lnternal energy measures
Esrael
Two bodies attract each other electrically. Do they both have to be charged? Answer the same question if the bodies repel one another.
JALLAH Reply
No. According to Isac Newtons law. this two bodies maybe you and the wall beside you. Attracting depends on the mass och each body and distance between them.
Dlovan
Are you really asking if two bodies have to be charged to be influenced by Coulombs Law?
Robert
like charges repel while unlike charges atttact
Raymond
What is specific heat capacity
Destiny Reply
Specific heat capacity is a measure of the amount of energy required to raise the temperature of a substance by one degree Celsius (or Kelvin). It is measured in Joules per kilogram per degree Celsius (J/kg°C).
AI-Robot
specific heat capacity is the amount of energy needed to raise the temperature of a substance by one degree Celsius or kelvin
ROKEEB
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Source:  OpenStax, Digital signal processing - dsp. OpenStax CNX. Jan 06, 2016 Download for free at https://legacy.cnx.org/content/col11642/1.38
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