Babu Madhav Institute of Information Technology, UTU Communication Systems

Transcription

1 Unit 1. Telecommunication Systems and Networks Short Questions 1. Define Telecommunication. 2. What is the functionality of POTS? 3. What do you mean by circuit-switched connection? 4. What SS7 is consist? 5. What is Electromagnetic spectrum? 6. PSTN interoffice call is made through which line? 7. What is quadrature amplitude modulation? 8. List out three application of the wireless network. 9. What is the function of main distribution frame? 10. What is the function of trunk distribution frame? 11. What are forward and reverse channel used in telecommunication system? 12. What is the function of control channel? What are its types? 13. What event triggers an AMPS handoff operation? 14. What two component of AMPS system provide air interface? 15. What is the purpose of release order message sent by AMPS system to mobile phone? 16. What is SID? 17. List two advantages of the use of digital encoding for cellular telephone system. Long Questions 1. Differentiate in-band and out-band signalling. 2. Discuss about today s existing network infrastructure with proper diagram. 3. Write a detail note on history and evolution of wireless radio systems. 4. Compare and contrast early and latest telecommunication system in terms of signalling. 5. For a city there are two local telephone exchanges are namely Exchange 1 and Exchange 2 respectively. If the user A from Exchange 1 calls to user B located in Exchange 2, describe how the call is setup? Also state component involve establishing the call. 6. Describe the public data network in detail using diagrams. 7. Write a detail note on broadband cable system with proper diagrams. 8. Draw a conceptual structure of the Internet and explain it in detail. 9. Describe a cellular telephone use that would be considering an infotainment use. 10. Explain the various wireless network applications. 11. Differentiate connection less and connection oriented with respect to telephone systems. 12. Write a detail note cellular telephone concept. 13. Explain the PSTN in detail with necessary diagrams. 14. Explain the network elements of the Signalling System #7 system. 15. Compare and contrast 1G, 2G, 2.5G, 3G and 4G network. 1

2 Multiple Choice Question 1. In connection oriented architecture a) you need to establish communication b) sometime connection requires c) connection is not required d) connection is establish 2. In Telecommunications, PCM is known as a) Pulse-case modulation b) Pure-code modulation c) Prime-code modulation d) Pulse-code modulation 3. The interface local exchange or Mobile switching center with signal transfer point. a) STP b) SCP c) SSP d) RCL 4. The use In Band Signaling. a) PDN b) CCIS c) PSTN d) SS#7 5. GSM is used in. a) Voice Network b) Data Network c) Both d) None of above 6. IEEE used for. a) Bluetooth b) MAN c) WAN d) Wireless LAN 7. AMPS (Advanced Mobile Telephone System) is of a) India b) UK c) US d) France 8. Which of these are Digital Cellular Technologies a) IS:54 / IS -136 N-America b) GSM Europe and Asia 2

3 c) IS-95 N America d) All of the above 9. known as father of Radio. a) Greham bell b) Macroni c) Fessden d) None of above 10. Combinations of dots & dashes used for alphanumeric characters is known as a) Macroni Code b) Morse Code c) Hertz Code d) All of above 11. PDN Stands for. a) Public Data Network b) Private Digital N/w c) Both A & B d) None of above all 12. VPN means. a) Virtual Public Network b) Virtual Processors Network c) Virtual Private Network d) All of above 13. RCL stands for. a) Remote Computer Link b) Remote Communication Lab c) Redundant Communication Links d) None of above 14. NAP means. a) National Access Point b) Network Access Points c) Neutral Access Point d) Network automated Points 15. ADSL stands for. a) Advance Digital Subscriber Line b) Adaptive Digital Subscriber line c) Advance Direct Service Link d) Automatic Direct Synchronous Link 16. The American Telephone & Telegraph (AT&T) was founded in which year? a)

4 b) 1865 c) 1875 d) Which is the faster way of communication? a) Twisted pairs b) Coaxial cables c) Optical fiber d) All 18. What is the type of signalling used between two exchanges? a) inband b) common channel signaling c) Both a & b 19. The situation when both transmitter and receiver have to work in tandem is referred to as a) parallel b) serial c) synchronous d) asynchronous 20. Trunks are the lines that run between a) subscribers and exchange b) switching system and power palnt c) local area network d) switching station 21. Common channel signalling in SS7 is a) out band control channel b) in band control channel c) speech control channel Fill in the Blanks 1. AM Stands for. 2. FM stands for. 3. PDN N/W is used to provide services (data, Voice). 4. AMPS system used channel spacing. True/False 1. Local Exchange & Company office both is same. 2. QAM is a digital modulation technique. 3. SS#7 use out band signaling. 4. Today s existing infrastructure consisting of both PSTN & PDN. 5. Wireless Access Point is a device that allows computers to access a wired n/w 4

5 using radio waves. 6. Broadband is a high capacity telecommunication pipeline capable of providing high speed Internet service. 7. Bandwidth refers to the capacity of communication line. 8. QAM is a hybrid form of amplitude and phase modulation. 9. Connection Oriented and Connection less services both are same. 10. Trunk Line is a line which connects a local exchange with another local exchange. 11. Modem Stands for Modulator Demodulator. 12. Internet is network of networks. 13. In internet routers are connected by WAN backbone. 14. Wireless Local Area N/w is popularly known as WLAN. 15. Raw transmission of bits is responsibility of Physical Network. 16. Wireless Access Point is a device that allows computers to access a wired n/w using radio waves. 17. The GSM, TDMA, CDMA, CDPD are all 2G technologies. 18. The GPRS was designed to provide voice services at higher data rates. 19. The first generation cellular system used analog frequency modulation schemes for the transmission of voice message. 20. The 1G cellular system uses time division multiplexing to increase system capacity. Unit 2. GSM Technology Short Questions 1. What is the standard bandwidth of a GSM channel? 2. Name the three major subsystem of a GSM wireless cellular network. 3. Give the duration of single timeslot of a TDMA frame in microseconds? 4. What is the purpose of the GSM burst training sequence? 5. What is the purpose of flag bit used in normal burst? 6. Which are the two states in a mobile can be? 7. What GSM control channel is specifically tasked with the facilitating of the handover operation? 8. The GSM MS roaming number is constructed according to what numbering plan? 9. What purpose does the TMSI number have? 10. Define the "attached" condition for a GSM mobile. 11. Define the "detached" condition for a GSM mobile. 12. What is the purpose of periodic location updating? 13 What is the basic difference between intra-bsc handover and inter-bsc handover? 14. What is the basic difference between inter-bsc handover and inter-msc handover? 15. What is the first operation performed by a NA-TDMA mobile upon powering up? 16. List the operations performed during a call setup. 17. Why there is a difference of three timeslots between uplink and downlink TDMA frame? 18. Provide the uplink frequency range for primary GSM-900 band. 5

6 Long Questions 1. Looking at the HLR/VLR database approach used in GSM - how does this architecture limit the scalability in terms of users, especially moving users? 2. What is the duration of GSM air interface timeslot? Also prove that the overall bit rate over the air interface is approximately kbps for GSM system. 3. Name the main elements of the GSM system architecture and describe their functions. What are the advantages of specifying not only the radio interface but all the internal interfaces of the GSM System. 4. Describe the function of MS and SIM. Why does GSM separate the MS and SIM? 5. The maximum distance allowed by the Timing Advance between the mobile station and base transceiver system in GSM system is 35 km. Justify your answer. 6. Describes the GSM TDMA timeslot. 7. Contrast the GSM hyperframe, superframe, multiframe, and TDMA frame. 8. Provide the structure and use of normal burst and frequency correction burst. 9. What is the function of the GSM access burst? 10. What is the purpose of the GSM dedicated control channels? 11. How does the GSM mobile station know what paging group it belongs to? 12. State the reason behind the delay of three timeslot between uplink and downlink frame. 13. Why are there several types of GSM multiframes? 14. What basic functions are located within the connection management sublayer? 15. What is location updating? Explain the IMSI detach and attach location updating. 16. Explain the network switching system (NSS) of GSM network in detail. 17. Contrast the required bandwidth requirements of AMPS, GSM, and NA-TDMA. 18. Explain in detail the concept of GSM TDMA frame structure. 19. What are the two protocol stacks within the MSC node for a GSM system? 20. Show the steps of interrogation operation performed during call setup using a timeline diagram. 21. Explain the authentication operation of call setup using necessary diagram. 22. What is a GSM SIM card? What purpose does it serve? Multiple Choice Question 1. The Primary GSM 900 used to MHz uplink frequency band. a) b) c) d) The interface exists in GSM system that have separate units for the transcoder controller and base station controller. a) A Inteface b) Um Interface c) Abis Interface d) Ater Interface 6

7 3. In GSM cellular system each carrier frequency can be shared up to how many users? a) 2 b) 4 c) 8 d) The total number of channels for GSM 900 is. a) 2992 b) 992 c) The MS is the device that provides the radio link between and. a) GSM subscriber and wireless mobile network b) MSC and BSC c) MSC and RBS 6. In the GSM standard, the MS consisting of which to elements a) mobile equipment and SIM card b) RBS and mobile equipment c) RBS and TRC 7. Which are the two elements of base station system (BSS)? a) a mobile station and a radio base station b) a radio base station and mobile switching centre c) a base transceiver system and the base station controller 8. An RBS in GSM cellular system is consisting of how many BTS that service a standard sectorized cell site? a) 2 b) 3 c) 4 d) 1 9. The is used by the GSM system to provide number portability to subscriber. a) visitor location register b) home location register c) flexible numbering register d) equipment identity register 10. Which of the following component provide surveillance of the entire network in GSM system. 7

8 a) Operation and Support System b) Mobile Switching Centre c) Network Switching System 11. Which interface is exists between the BSC and BTS? a) A Inteface b) Um Interface c) Abis Interface d) Ater Interface Fill in the Blanks 1. For GSM cellular system the air interface consists of channels that have a frequency separation of khz. 2. The GSM 1800 band has carrier frequencies. 3. In the GSM standard, the MS consisting of and. 4. The BSC and BTS communicate with each other using protocol in GSM cellular system. 5. The NSS will use to redirect messages sent by a GMSC toward a particular HLR to the correct HLR TDMA frame = Timeslots ms Hyperframe = Superframes = TDMA frames 8. The is used by GSM system to reduce the number of steps required for call setup. True/False 1. Hand over occurs when an inactive mobile station changes cells. 2. The GSM cellular system supports subscriber's roaming mobility through location updating operation only. Unit 3. CDMA Technology Short Questions 1. What does the term CDMA stands for? 2. What is the unique aspect of CDMA technology? 3. What ultimately limits the number of users of a CDMA cellular wireless system? 4. What are Walsh codes? 5. What is the length of the CDMA short PN spreading codes? 6. Of what use is the CDMA frame format in the context of paging channel operation? 7. What is the difference between the CDMA soft handoff and the CDMA softer handoff? 8. How many additional supplemental code channel may be supported by IS-95B? Long Questions 1. If the basic CDMA signal bandwidth is 1.25 MHz, why are allocated CDMA channels only separated by 50 KHz spacing in Band Class 0? 8

9 2. How can additional CDMA system capacity be achieved? 3. What is the function of the interworking function node in a 2G CDMA system? 4. What is the function of the mobile positioning system? 5. In a cdma2000 system, what is the function of the packet core network? What are its main components? 6. What is the function of the home agent in a cdma2000 system? 7. What is the function of the packet data serving node in a cdma2000 system? 8. How does the use of spreading codes increase signal bandwidth? 9. Describe how different base stations in a CDMA system are able to be differentiated by mobile stations. 10. Describe the generation of the IS-95 CDMA pilot channel. 11. Describe how the CDMA traffic channel is also able to provide power control information to the subscriber's mobile device. 12. How does the CDMA system differentiated uplink signals transmitted by different mobiles? 13. Describe the use of power control groups on the CDMA reverse traffic channels. What purpose do they serve? 14. Describe the three states that a CDMA mobile may be in while in the attached mode. 15. Describe the steps a CDMA mobile goes through in the initialization state. 16. Describe the CDMA soft handoff. 9