????S ? :

1
?????? ?????? ???????O??O?

• ????S ?
• ??????????O????? T?????
• ?????S??S? ??. 1
• ??S?GOG?

2
?s??µate? ?p????????e? ?st????? a?ad??µ?

• Before the Birth of Radio'', 1867-1896
• 1820 Oersted demonstrated that an electric
  current produces a magnetic field
• 1831 Faraday showed that an induced current is
  produced by moving a magnet in the vicinity of a
  conductor (i.e. a changing magnetic field
  produces an electric field)
• 1867 Based on the above background Maxwell
  predicted existence of electromagnetic (EM) waves
  and formulated the basic theory
• 1887 Hertz proved existence of EM waves a
  transmitter generated a signal in a receiver
  several meters away
• 1890 Branly developed coherer for detecting
  radio waves
• 1896 Guglielmo Marconi demonstrated wireless
  telegraph to English telegraph office

3
?s??µate? ?p????????e? ?st????? a?ad??µ?

• The Birth of Radio
• 1897 Marconi awarded patent for wireless
  telegraph
• 1897 First Marconi station'' established on
  Needles island to communicate with English coast
• 1898 Marconi awarded English patent no. 7777 for
  tuned communication
• 1898 Wireless telegraphic connection between
  England and France established

4
?s??µate? ?p????????e? ?st????? a?ad??µ?

• Transoceanic Communication
• 1901 Marconi successfully transmitted radio
  signal across Atlantic Ocean from Cornwall to
  Newfoundland
• 1902 First bidirectional communication across
  Atlantic
• 1909 Marconi awarded Nobel prize for physics

5
?s??µate? ?p????????e? ?st????? a?ad??µ?

• Voice over Radio
• 1914 First voice over radio transmission
• 1920s Mobile receivers installed in police cars
  in Detroit
• 1930s Mobile transmitters developed radio
  equipment occupied most of police car trunk
• 1935 Frequency modulation (FM) demonstrated by
  Armstrong
• 1940s Majority of police systems converted to FM
  
• Developments in electronics (vacuum tube,
  transistor, IC)

6
?s??µate? ?p????????e? ?st????? a?ad??µ?

• Cellular Mobile Telephony
• 1979 NTT/Japan deployed first cellular
  communication system
• 1983 Advanced Mobile Phone System (AMPS)
  deployed in US in 900 MHz band supports 666
  duplex channels
• 1989 Groupe Spècial Mobile defined European
  digital cellular standard, GSM
• 1991 US Digital Cellular phone system introduced
  (IS-54)
• 1993 IS-95 code-division multiple-access (CDMA)
  spread- spectrum digital cellular system deployed
  in US
• 1994 GSM system deployed in US, relabeled
  Global System for Mobile Communications''

7
?s??µate? ?p????????e? ?st????? a?ad??µ?

• PCS and Beyond
• 1995 International and national level boards
  auctioned off new frequency bands for Personal
  Communications Systems (PCS) at 1.8 GHz
• 2000 Third generation cellular system standards
  started being established
• 2001 Number of cellular telephone users more
  than 700M worldwide (10M in 1990)
• Today and the coming years intensive research
  efforts towards next generations

8
????t?? ep????????e? Ge????

• ????t? as??µat? t??ef???a ?p??es?a µet?d?s??
  f????, s?st?µa GSM, DCS-1800 , 2.5 G, 3G
• ??e? as??µate? ?p??es?e? (e????a, ß??te? )
• apa?t?s? ??a ??????? ???µ??? µet?d?s?? t??
  t??e?? t?? µe????? Mb/s
• as??µat? µet?d?s? p???d??de?s? t?? s?µat??,
  d?as?µß????? pa?eµß???, ?e???te?e?e? ?s?
  a????eta? ? ???µ?? µet?d?s??
• ????p???? ??f?a?? epe?e??as?a
• ???a s?st?µata
• Radio paging systems
• Cordless telephony
• WLAN

9
????t?? ?p????????e? Ge????

• ???s?µ?p?????ta? p???ap??? a?aµetad?te? µe
  p?µp??? ?aµ???? ?s???? ( Pt lt 100W)
• ? ??? pe????? e?d?af????t?? ?p?d?a??e?ta? se
  ?p?pe?????? (?????e?)
• Se ???e ?????? (cell) a?t?st???e? ??a?
  a?aµetad?t?? ? sta?µ?? ß?s?? (base station) p??
  pe???aµß??e? p?µp?, d??t? ?a? e?e??t? (??a µ?a
  ?µ?da ap? BS).
• St?? pe????? e?????? t?? ???e sta?µ?? ß?s??
  a?at??e?ta? s???e???µ??e? ???e? s????t?t??.

10
????t?? ?p????????e? ? ?d?a t?? ???????
11
????t?? ?p????????e? ???t?pa ???e??? se ???t?a
p??e??
12
????t?? ?p????????e? Cell clusters
13
????t?? ?p????????e? ???p?? d??d?s??
LOS, Reflection, Diffraction, Scattering
14
????t?? ?p????????e? Ge???? pe????af? t??
s?st?µat??
15
????t?? ?p????????e? ?e?t??????? d????aµµa

• Mobile Switching Center (MSC) also connected to
  
• Home Location Register
• Visitors Location Register
• Authentication Center
• Operation and Maintenance Center

16
S?st?µa GSM
17
S?st?µa GSM

• ?????????da 0.577 ms ??a ???e ???st?, µ?a ?µ?da 8
  ?????????d?? ?a?e?ta? TDMA frame ?a? µetad?deta?
  ???e 4.615 ms
• s??????? µetad?d??ta? 156.25 bit sta 0.577 ms,
  gross bit rate 270.833 kbps
• ? a???????a e?µ???s?? t?? 26 bit ???s?µ?p??e?ta?
  ??a t?? ?s?st??µ?s?
• ? ?s?st??µ?s? ?e?t????e? d?e?e????ta? t? p?? ?
  ???st? e?pa?de?t??? a???????a ep??e??eta? ap? t??
  p???d??de?s?
• ? ???p???s? t?? ?s?sta?µ?st? de? p??sd?????eta?
  st?? p??d?a??af?? t?? GSM

18
S?st?µa GSM
UMTS GPRS, EDGE General packet radio
services Enhanced data for GSM
evolution GSM, DCS
19
?p?µe?e? ?e???? ??e? p?????se??

• S?st?µata ???? (Multiple-Input Multiple-Output)
• ???a?a a?t?µet?p?s? t?? d?ad??as??? ??aµ??f?s?
  ?s?st??µ?s? ??d???p???s? ??a????
• ???sa?µ?st???? d?aµ??f?se??. ??t?µet?p?s? t?? µ?
  ??aµµ???t?t??.
• T?µata ???p???se?? (apa?t?se?? p?a?µ. ??????,
  pe?????sµ??? ?ata????s?)
• ?e?t?st?p???se?? µe s??e??as?a ep?p?d?? (a???s?
  ?????? ????t???t?ta?, e??es? ??s?? ??p)

20
???ß??µata sta ?p??a ?a est??s??µe

• ??a???? ????t?? ?p????????a?
• ?d?a?te?a ?a?a?t???st???
• ???te??p???s?
• ?e?????? ??d???p???s?? ????? ?µfas? st??
  pe??pt?s? t?? F????
• ?p?d?t???? ?e?????? ??f?a??? ??aµ??f?s??
• ?s?st??µ?s? (???s?s?) ??a???? ??af??et???t?ta
  ????? ?a? e?p?µp?? (diversity)