GSM Mobile Communication Interview Written Test Questions
1. The co-channel interference in cellular systems is a function of
a) Distance between co-channel cells.
b) Radius of cell
c) The ratio of distance between co-channel cells to radius of cell.
d) Square of distance between co-channel cells.
2. Larger cells are more useful in
a) Densely populated urban areas.
b) Rural areas
c) Lightly populated urban areas
d) Mountainous areas.
3. In a PLMN the cell shape is always hexagonal.
4. In equation D/R= √3K which one of the following is not valid value of, K the reuse factor ( where D = distance between two co-channel cells and R= radius of a co-channel cell)
a)7 b) 5 c) 12 d) 19
5. The first cellular systems were
6. In case of propagation near ground level in an urban environment, the received power varies typically with d-4 . (Where d is distance of receiving point from transmitting station.)
7. Access method in GSM is based upon-
c) Both TDMA and FDMA
d) None of these.
8. In GSM use of which of the following technique does not result in reduction of interference level in a cell.
a) sectorization of a cell.
b) Frequency Re-use.
c) Transmitted power control.
d) Discontinuous transmission.
9. In up-link direction ARFCN (Absolute Radio Frequency Carrier Number) of 100 corresponds to frequency of (where 1 ≤ ARFCN ≤ 124)
a) 909.8 MHz (b) 910MHz (c) 910.2 MHz (d) 910.4MHz
10. Cells in one Location Area can be served by different VLR’s.
11. Authentication triplet used for authentication of subscriber and ciphering of data over radio interface consists of
a) RAND, Ki, SRES
b) RAND, Kc, SRES
c) A5, RAND, Ki
d) A3, RAND, Kc
12. Authentication triplet required for authentication procedure are stored at-
a) HLR b) EIR c) AuC d) VLR
13. Ciphering key Kc is never transmitted over radio interface. True/ false
14. Subscriber Identification key Ki is stored at
a) VLR b) SIM card c) MSC d) HLR and SIM card
15. For intra-BSC normal Hand-over (not forced Hand-over) unit responsible for taking a decision that Hand-over is required
a) BSC b) MSC c) VLR d) HLR
16. Unit responsible for implementing power management of BTS’s by broadcasting minimum power level is
a) BTS b) BSC c) MSC d) HLR
17. MSRN, a temporary number used to route the call has significance in case of
1.Mobile Originated Call (Mobile to PSTN)
2.Mobile Terminated Call (PSTN to Mobile)
3.Mobile to Mobile Call
b) 1 only
c) 2 only
d) 1 and 2
e) 2 and 3.
18. Which of the following statements about BCCH is not true-
a) It is a beacon on signal.
b) It is a point to multi-point channel and is defined in downlink direction (BTS to MS) only.
c) BCCH carrier is power controlled to reduce interface level in a cell.
d) It contains information about system configuration parameters (e.g. LAI, cell id, neighbouring cells etc) for MS.
19. When MS is in dedicated mode, the information for non urgent procedure like radio link supervision measurement, transmit power control and timing advance data, is carried on-
a) SDCCH b) FACCH c) SACCH d) RACH
20. FACCH is essentially a traffic channel with stealing flag set high to denote that information carried is control data and not a traffic data.
21. The call set-up information (Dialled digits etc.) is transferred on air-interface on.
a) SACCH b) FACH c) SDCCH d) RACH
22. SDCCH is half-duplex channel used for signalling in higher layers. True/ false.
23. BCCH is always transmitted on time slot 0 of the carrier. True/ false.
24. In case inter-MSC Handover, MSC to MSC communication makes use of-
a) MAP- D interface.
b) MAP- C interface
c) MAP- E interface.
d) A-bis interface.
25. The maximum data rate supported by GSM system is
a) 4800bps b0 5600bps c) 9600bps d) 19200bps.
26. In GSM the signalling protocol supported BTS and BSC is
a) LAPD b) LAPDm c) SS7 d) CAS.
28. Write down the names of three technology options for WILL.
29. Name three multiple access techniques for radio systems.
30. Write two major advantages of CDMA system.
Better Spectral Efficiency.
31. Match the following.
Walsh Codes 64
2nd Generation Mobile tecnology
GSM 2nd Generation Mobile tecnology
7 / 21
1 / 3
Mobility Management HLR
GSM RF Carrier 200 khz
CDMA RF Carrier 1.25 Mhz
32. Write True (T) or False (F)
(a) Sectorization helps to reduce interference. T
(b) One DIU can typically handles 1000 subscriber. T
(c) A-bis GSM Standard Interface . T
(d) DECT is macro cellular architecture. F
33. Write down two major advantages of WILL over PSTN.
1. Free from last mile problems.
2. Clearing waiting list in TNF areas.
34. Name Two forward link Channel in CDMA Sysyem.
1. Pilot Channel 2. Sync. Channel.
35. Name two types of handoff in CDMA System
1. Softer handoff 2. Soft Handoff.