Continuous Signals and Linear Systems

Daffodil International University Department of Electrical and Electronic Engineering Faculty of Engineering Midterm Examination, Fall – 2026 Course Code: 0714-133 Course Title: Continuous Signals & Linear Systems Section: A, B Level-Term: L1-T3 Teacher's Initial: SKS Full Marks: 25 Exam Date: 31 October, 2026 Time: 1.5 Hours All questions are compulsory. The second rightmost column indicates the corresponding Course Outcomes (COs) along with their respective Bloom's Taxonomy levels, and the rightmost column indicates the allocated marks for each question. Q1. a) Identify whether or not the following signal is periodic. If a signal is periodic, find its fundamental period: x(t) = sin(3πt/4) + cos(πt/2) b) Identify the even and odd components of the following signal: x(t) = 10sint + 5cost – 4cost.sint CO-1 C (2) | 5 Q2. Express the pulse (or rectangular) given in the following Fig.1 in terms of the unit step. Calculate its derivative and sketch it. [Figure: Graph of rectangular pulse v(t) with amplitude 8 from t = 3 to t = 6] Fig. 1. CO-1 C (2) | 5 Q3. A continuous-time signal x (t) is shown in the following Fig. 2. Sketch and label each of the following signals: (a) -x(t); (b) 2x(-t); (c) 2x(t+3); (d) 4x(t-2); (e) x(t) + 3 [Figure: Graph of signal x(t) with a ramp from (-2, 0) to (0, 1) and a square step of value -1 from t = 0 to 1] Fig. 2. CO-1 C (2) | 5 Q4. Determine whether the following signals are time variant or time invariant signals. (a) y(t) = x^2(t) (b) y(t) = cos(t) x(t) (c) y(t) = x(t-2) 3x(t) CO-1 C (3) | 5 Q5. The input x(t) and the impulse response h(t) of a continuous time LTI system are given by x(t) = u(t), h(t) = e^-3tu(t). Compute the output response y(t)= h(t)* x(t). CO-1 C (3) | 5