31. 


Answer: (b)

32. What is the far field distance for an antenna with largest dimension 1.5 m and the corresponding frequency of 1200 MHz ?
(a) 12 𝑚
(b) 3 𝑚
(c) 6 𝑚
(d) 8 𝑚

Answer: (No correct answer)

33. The block length and size of check code in Reed-Solomon code for 𝑚 = 2 and 𝑡 = 1 are respectively:
(a) 4 bits and 6 bits
(b) 6 bits and 6 bits
(c) 4 bits and 4 bits
(d) 6 bits and 4 bits

Answer: (d)

34. 
(a) 38.36 Watts
(b) 28.26 Watts
(c) 32.16 Watts
(d) 18.89 Watts

Answer: (a)

35. A telephone voice transmission needs transmission of recurrences up to 3.6 kHz , the broadcast video using North American standard needs transmission of frequencies upto 4.5 MHz . If certain modulation scheme requires 10 KHz for its audio transmission, the bandwidth required to transmit video using the same scheme is:
(a) 08.5 MHz
(b) 10.0 MHz
(c) 12.5 MHz
(d) 15.0 MHz

Answer: (c)

36. A vehicle travels through the cellular mobile system at 150 kmph. How often handoffs take place if the cell radius is 4 km?
(a) 192.3 sec
(b) 180.3 sec
(c) 163.5 sec
(d) 150.9 sec

Answer: (a)

37. A truck travels at 65 km in 1 hour and if it uses a PCS phone at 1900 MHz , the time period between the fades is:
(a) 5.9 m/sec
(b) 4.4 m/sec
(c) 8.3 m/sec
(d) 6.1 m/sec

Answer: (b)

38. What is the bandwidth efficiency if a 𝜋/4 DQ PSK supports data transmission of three various 48.6 kB/sec digitized voice signal in a bandwidth of 30 kHz?
(a) 6.66 bytes/sec/Hz
(b) 5.75 bytes/sec/Hz
(c) 4.86 bytes/sec/Hz
(d) 3.96 bytes/sec/Hz

Answer: (c)

39. 
(a) 50 ms and 40 ms
(b) 40 ms and 40 ms
(c) 50 ms and 0.02 ms
(d) 40 ms and 0.02 ms

Answer: (c)

40. A bandwidth of 100 kHz spans 200 kHz to 300 kHz . If the data is modulated by using ASK with 𝑑=1 and 𝑟 =1 the carrier frequency and bit rates are:
(a) 110 kHz and 30 kbps
(b) 100 kHz and 50 kbps
(c) 110 kHz and 50 kbps
(d) 100 kHz and 30 kbps

Answer: (b)