1. The minimum SNR (in dB) required to achieve the capacity of 10 bps/Hz is approximately

• 22 dB
• 28 dB
• 30 dB
• 35 dB

Answer :- c

2. The number of slots/subframe if the system uses a sub-carrier spacing of 60kHz

Answer :- 4

3. The system which is using incremental redundancy retransmission mode with an effective code rate of 3/4 did an initial transmission. But the receiver failed to successfully decode the data in first attempt and asked for 2 more retransmissions. Calulate the code rate at which the receiver was able to successfully decode the data

• 1/4
• 3/4
• 3/8
• 3/16

Answer :- a

4. The 5G system has been designed with the following specifications:
(i) Bandwidth = 50 MHz, with usable bandwidth begin 49.5 MHz
(ii) Subcarrier Spacing, ∆f = 15kHz
(iii) Uses N = 4096 point FFT
Calculate ceil(Sampling Rate/10⁶)

Answer :- 62

5. The 5G system has been designed with the following specifications:
(i) Bandwidth = 50 MHz, with usable bandwidth begin 49.5 MHz
(ii) Subcarrier Spacing, ∆f = 15kHz
(iii) Uses N = 4096 point FFT
Calculate Slot Duration(in ms) ×Subframe Duration (in ms)

Answer :- 10

6. The 5G system has been designed with the following specifications:
(i) Bandwidth = 50 MHz, with usable bandwidth begin 49.5 MHz
(ii) Subcarrier Spacing, ∆f = 15kHz
(iii) Uses N = 4096 point FFT

Calculate the CP length of the first symbol if rest of the symbols in slot have a CP length of 288 samples.

Answer :- 352

7. The system uses a Modulation Scheme with the following specifications:

Modulation Order = 2
Target Code Rate (1024 x R) = 894

Calculate it’s spectral efficiency

• 0.8730
• 1.7461
• 1.8951
• 1.9541

Answer :- b