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I. Study Guide: 
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A. General Guideline:

1. Study the summary in each chapter.
2. Study the lecture notes.
3. Study the homeworks.
5. Study the textbook.
6. Do the exercises.

B. Review for the Mid-term:

1. Understand the basic terminologies.
2. Understand fundmentals of mobile and wireless communications (Chap 1)
3. Understand wireless transmission media (Table 2.1) (Chap 2)
4. Understand wireless medium access control (Table 3.1) (Chap 3)
5. Understand main mobile/wireless telecommunications systems (GSM) (Chap 4)

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II. Sample Questions:
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A. Multiple Choice Questions:

(A) 1. The typical desktop computer in an office falls into the category of:
       (A) fixed and wired (B) mobile and wired 
       (C) fixed and wireless (D) mobile and wireless

(C) 2. In what band do most cellular and wireless LAN systems operate?
       (A) HF (B) VHF (C) UHF (D) SHF

(B) 3. The wavelength of 1 GHz frequency is
       (A) 3 cm (B) 30 cm (C) 300 cm (D) 3000 cm
  
(C) 4. The frequency of 10 cm wavelength is
       (A) 300 MHz (B) 1 GHz (C) 3 GHz (D) 30 GHz

(D) 5. DECT is a standard for
       (A) trunked radio (B) mobile phone (C) LAN (D) cordless phone

(A) 6. The antenna size for GSM 1800 is
       (A) 4 cm (B) 8 cm (C) 10 cm (D) 18 cm

(D) 7. Which is not a wave propagation behaviors (modes)?
       (A) ground wave (B) sky wave (C) line-of-sight (D) none of the above

(C) 8. Which ware propagation behaviors is preferred for mobile phone systems?
       (A) ground wave (B) sky wave (C) line-of-sight (D) none of the above

(A) 9. The propagation effect that occurs because the velocity of the
       electromagnetic waves depends on the density of the medium through
       which it travels is
       (A) refraction (B) blocking (C) reflection (D) diffraction

(D) 10. Which is not the modulation method?
       (A) amplitude (B) frequency (C) phase (D) time

(B) 11. A medium can carry 8 Kbaud. Which scheme can achieve the 32 Kbps 
       transfer rate?
       (A) QPSK (B) QAM-16 (C) QAM-64 (D) QAM-128
       
(D) 12. Which is not the advantage of cellular systems?
       (A) higher capacity (B) less transmission power  
       (C) local interference only (D) none of the above

(B) 13. Which can achieve best channel utilization in high load?
       (A) slotted ALOHA (B) 0.01-persistent CSMA  
       (C) 1-persistent CSMA (D) nonpersistent CSMA
     
(B) 14. Consider a sender A wants to send the data bit 1 with key = 010011.
        Assume we code a binary 0 as -1, a binary 1 as +1. What will be sent?
       (A) (+1, -1, +1, +1, -1, -1) (B) (-1, +1, -1, -1, +1, +1) 
       (C) (-1, +1, +1, +1, +1, +1) (D) (-1, +1, -1, -1, -1, -1) 

(A) 15. Which is not security components used in GSM?
       (A) HLR (B) SIM (C) EIR (D) AuC

(C) 16. Which is not a GSM subsystem?
        (A) RSS (B) NSS (C) DSS (D) OSS

(A) 17. Which does not belong to RSS?
        (A) MSC (B) MS (C) BTS (D) BSC

(B) 18. Which is used to connect to ISDN or PSTN in GSM?
        (A) BSC (B) GMSC (C) MSC (D) BTS 

(D) 19. Which is not a GSM security service?
        (A) access control and authentication
        (B) confidentiality
        (C) anonymity
        (D) none of the above

(D) 20. Which statement about GRPS is false?
        (A) GPRS is Packet-switched. 
        (B) GPRS can achieve higher transfer rate than HSCSD.
        (C) GPRS provides the QoS selection.
        (D) The maximun rate transfer for GRPS is 57.6 kbps (duplex).

(B) 21. Which belongs to IMT-MC?
        (A) W-CDMA (B) CDMA2000 (C) TD-CDMA (D) EDGE

(C) 22. UMTS uses a constant chipping rate of 3.84 Mchps/s. A channel
        use the spreading factor 8. What is the transfer rate?
        (A) 120 kbps (B) 240 kbps (C) 480 kbps (D) 960 kbps


B. Question and Answer:

1. Define the following:

  A. GSM
  B. UTMS
  C. TETRA
  D. DECT
  E. PDC
  F. FOMA
  G. DSSS
  H. FHSS
  I. CSMA/CD
  J. CSMA/CA
  K. CDMA
  L. GPRS
  M. OVSF
 

2. What are 4 dimensions of multiplexing for wireless communication?

Ans: space, frequency, time, code

3. What is digital modulation? Why is digital modulation required? 
   What is analog modulation?

4. Why a baseband signal cannot be directly transmitted in a wireless
   system?

5. What is DSSS? Which telecommunication system uses DSSS? 
   What is FHSS? Which telecommunication system uses FHSS? 

Ans: CDMA and Wireless LAN use DSSS.
     Bluetooth and GSM use FHSS.

6. What is FCA? What is DCA?

7. Describe the problems when CSMA/CD is applied to wireless networks.
   What methods could solve the problems?

8. What is a good code for CDMA?

9.  Consider a sender A wants to send the data bit 1 with key = 010011.
    Consider a sender B wants to send the data bit 0 with key = 110101.
    Assume we code a binary 0 as -1, a binary 1 as +1.
    Both signals are transmitted at the same time. The noise to 
    the transmitted signal is (-2, 0, 0, -2, +2, 0).  
    What signal is received at a receiver? 
    Can the data sent by A and B be recognized?

10. Describe MTC and MOC in GSM.

11. Describe authentication and encrption of GSM.

12. Describe 5 groups of 3G radio access technolgoies.

Ans: IMT-DS, IMT-TC, IMT-MC, IMT-SC, IMT-FT