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For signal v(t)=j2sin(2π×4t)+4cos(2π×8t), determine (a) period, (b) Fourier Series form III, (c) Fourier Transform, (d) Power Spectral Density function, (e) Autocorrelation function, (f) total power, (g) total energy. [5+7+8+10+5+5+5=45]

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Final answer:

The signal v(t) has distinct sine and cosine components with different frequencies and periods. Techniques such as Fourier Transform and Power Spectural Density functions are used to analyze and characterize the signal's frequency content, power distribution, and other properties.

Step-by-step explanation:

The signal v(t)=j2sin(2π×4t)+4cos(2π×8t) contains two sinusoidal components, one sine, and one cosine wave. To determine the components of this signal, such as period, Fourier Series, Fourier Transform, Power Spectral Density function, Autocorrelation function, total power, and total energy, various signal processing techniques must be employed.

(a) To find the period of each component, one should look at the coefficients of t inside the sine and cosine functions. For the sine component, the frequency is 4 Hz, yielding a period of 1/4 (or 0.25s). For the cosine component, the frequency is 8 Hz, which gives a period of 1/8 (or 0.125s). The total period of the signal will be the least common multiple of these two periods.

(b) The Fourier Series form III is a representation of a periodic signal as a sum of sine and cosine functions (harmonics) with different frequencies. Since the given signal is not periodic, it does not have a typical Fourier Series representation.

(c) The Fourier Transform is a mathematical transformation used to represent a function of time into a function of frequency. It identifies the different frequencies present in the signal and their amplitudes.

(d) The Power Spectral Density (PSD) function shows how the power of a signal is distributed across different frequency bands.

(e) The Autocorrelation function represents how the signal correlates with a delayed version of itself as a function of the delay.

(f) The total power of a signal can be calculated by integrating the power across all frequencies, which is derived from the PSD.

(g) The total energy of a signal is determined by integrating the square of the signal over all time, which for a continuous-time signal is given by the area under the squared signal.

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