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An AM - signal is given as x(AM) (t) =...

An AM - signal is given as
`x_(AM) (t) = 100[ p (t) + 0.5g (t) ] cos omega_c t` in interval `0 le t lt 1 `. One set of possible values of the modulating signal and modulation index would be

A

`t,0.5`

B

`t,1.0`

C

`t,1.5`

D

`t^(2), 2.0`

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The correct Answer is:
To solve the problem, we need to analyze the given AM signal and determine the modulating signal and the modulation index. ### Step-by-Step Solution: 1. **Identify the Given AM Signal:** The AM signal is given as: \[ x_{AM}(t) = 100 \left[ p(t) + 0.5 g(t) \right] \cos(\omega_c t) \] This is valid in the interval \(0 \leq t < 1\). 2. **Understand the Components of the AM Signal:** In the general form of an AM signal: \[ x_{AM}(t) = E_c \left[ 1 + m_a \cdot m(t) \right] \cos(\omega_c t) \] where: - \(E_c\) is the carrier amplitude, - \(m_a\) is the modulation index, - \(m(t)\) is the modulating signal. 3. **Compare the Given Signal with the General Form:** From the given signal, we can identify: - \(E_c = 100\) - The term \(0.5 g(t)\) suggests that the modulating signal is \(m(t) = p(t) + 0.5 g(t)\). - The modulation index \(m_a\) is \(0.5\). 4. **Determine the Modulating Signal:** We can choose a simple form for \(p(t)\) and \(g(t)\). For instance, let: - \(p(t) = 1\) (a constant signal), - \(g(t) = t\) (a linear signal). Thus, we can express the modulating signal as: \[ m(t) = 1 + 0.5t \] 5. **Identify the Modulation Index:** The modulation index \(m_a\) is already identified as \(0.5\). ### Final Answer: One set of possible values of the modulating signal and modulation index would be: - Modulating Signal: \(m(t) = 1 + 0.5t\) - Modulation Index: \(m_a = 0.5\)

To solve the problem, we need to analyze the given AM signal and determine the modulating signal and the modulation index. ### Step-by-Step Solution: 1. **Identify the Given AM Signal:** The AM signal is given as: \[ x_{AM}(t) = 100 \left[ p(t) + 0.5 g(t) \right] \cos(\omega_c t) ...
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