()=< a) Consider the case where a modulating tone v, a cos(2ft) is used in a...
A carrier signal c(?) = ? cos(??) is modulated by a single-tone signal ?(?) = ? ???(??) to form the AM signal: s(t)= [? + ????(??)]???(??), where ? = 10, ? = 2, ? = 1000 ??, ? = 50 ??. a- Obtain an expression for the sidebands of ?(?). b- Sketch ?(?) c- Sketch the spectra |?(?)|, |?(?)|, |?(?)| against f. d- Calculate the modulation index (m) e- What bandwidth is required to transmit the AM signal. f- Show...
3(a) A complex signal given by the expression cos (9t x 103t) Vm(t) %3D 0.5cos(Зл х 103t) + сos(8т х 103t) + is used to amplitude modulate a carrier signal, Vc(t) = 3cos(2n shown in Figure 3(a) 105t) as X Vm(t) 0.5cos(3t x 103t) cos(8T x 103t) AM Modulator AM Signal cos(9t x 10t) Vc(t) 3cos(2n x 105t) Figure 3(a) The AM signal in Question 3(a) is developed across 2.2 kn load resistance The modulated carrier in Question 3(a) is...
Consider an AM system. The message signal is given by cos(1000t) volts. The modulated signal is (0.5+acos(1000m))cos(2π.) volts, where α is a positive coefficient, and fe is the carrier frequency. (a) Determine the value of α when the modulation index is 100%. (b) Determine the value of α when the modulation index is 50%. (c) Determine the value of α when the modulation index is 200%. (6 marks) Continue from (1) and suppose α-05. Sketch the spectrum of the transmitted...
signals and communications 2 Make sure you show all working and describe each step in your calculations. 1. A signum function is defined as sgn(t) = { 1、12 0 1 t<0 Plot and express this function in terms of the unit-step function. 5 marks/ Determine and plot the even and odd parts of the signal 2. x(t) (te-3 +2)u(t). 5 marks 3. If prove that y[n-m] = x[n-m] * h[n]. 5 marks 4. Assuming α > 0, plot the signal...
below is used to modulate a carrier to generate the AM signal yt) (Am()) cos(1000t) The periodic signal m() shown a) The power efficiency of the system is measured to be 1 () The type of AM modulation, i.e. SSB, DSBSC, (i) The constant A. (ili) The modulation index 1/13. Determine DSB with carrier enit -3 b) An angle modulated signal is given by d(t-2 cos (2n1061+ sin 2 1000). Find i) The carrier frequency. ii) The baseband signal bandwidth....
4.(30p) A message signal is consisting of voice signal and information code as shown in the figure. This signal modulates an AM carrier signal x(t) defined as x(t) = cos(2 *T*50000*t) Find and sketch the spectrum of the modulated signal for each AM modulation type below. Explain the advantages and disadvantages of each modulation type. a) DSB-SC b) DSB c) SSB Upper Side Band AM(A) 2 a 1 2 -5 -4 -21 4 5 f (kHz)
1 2 4. The amplitude modulation signal is given by the following expression and is applied to 75 load. Vam(t) = 10 sin (21fct) - 2.5 cos (1500krt) + 2.5 cos (1450krt) V Determine: a) Modulation index b) The frequency of the carrier and the information signal c) The bandwidth d) The total power e) The transmission power efficiency be ar e 5. One of the inputs to a frequency modulator is a 250 kHz carrier signal with amplitude of...
4.(30p) A message signal is consisting of voice signal and information code as shown in the figure. This signal modulates an AM carrier signal x(t) defined as x(t) = cos(2 * 11 * 50000 *t) Find and sketch the spectrum of the modulated signal for each AM modulation type below. Explain the advantages and disadvantages of each modulation type. a) DSB-SC b) DSB c) SSB Upper Side Band AMEA)! 2 1 2 5 -5 2-1 f (kHz)
Suppose you wish to sample an amplitude modulated signal x(t)-m(t) cos(Q,t) where m(1) is the message signal and Ω,-2π 10 (rad/sec) is the carrier frequency 8.6 a) If the message is anacusic signal with frequencies in a band of [0, 22] kHz, what would be maximum frequency present in x(t)?
1. FM modulation. Consider a message signal m(t)-(2nt and a carrier wave c(t)-cos(400rt) (a) (20 points) Derive the FM modulated signal s(t) for ky-2 (b) (25 points) Find the Fourier transform, S(), of s(t) (Sketch to scale). (c) (5 points) What is the bandwidth of the modulated signal s(t).