Question

Question 2: (5 Marks Total) A] A transmitted signal travels a distance of 48 m during a time interval. If this distance is equal to 6 periods (6T): a) Calculate the wavelength for this signal. (2 Marks) b) Calculate the period "T" for this signal. (2 Marks) B] If the power gain for a system equals 4 dB, calculate this gain dBm. (1 Mark) Question 3: (2 x 3 Marks = 6 Marks) For the signals shown in Figure (2) (a) and (b) below, determine which of the signals may be characterized as power or as energy signal, then calculate the corresponding power or energy as applies for each case: 5 MAMM letamente g(t) Figure (2)

Answer 1

02 ffiver distance travelled = 48m distance travelled operiods. (a) wavelength = ? distance havelled an single period is wavelength (0) ::N = 48 6 2= 8 m (b) Time period t= ? We know a= velocity of light frequency ola uk f= С Where C= 36108 mis , n=8m 3x108 f = g 늦 X de f = 3x108 8. while Time period to at 8 ::T= 3X108 2.67X108

T= 2.67x108 sec T= 0.03678100 e sec B) power gain in dB = 4dB gain in dom za The unit dem denotes the absolute power level in de and referered to imW (1x 103 W) Thus formula used to convert dB to dom is dBm= 10 x logo Polpi Txo (a) calculate Po Pin We have dB = 4 pocuer gan logio ( )=4 10 X logio (Po 오 To, Pi Po = 2.512 w Pi llig substitute in ① dem z 10 109 (453) dem = tolog (9.512 x103)

dBm= 1010g 2.519 + lolog 109 dom - A+ 30 dBm = 34 dBm