1. Telecommunications
Transmission Medium

2. Topics to be discussed
Copper cable
Wireless
Fiber optics

3. Transmission mediums Things to be considered Frequency spectrum
Distance between repeaters
Distance α 1 Bit rate
Noise sensitivity
Security – OTDR
Cost
Acquisition
Installation and maintenance
Operational cost for enterprises
Transmission medium
Total data rate
Bandwidth
Repeater spacing (km)
BER
Twisted pair
100 Mbps
1 MHz
1.8
10-5
Coaxial cable
500 Mbps
1 GHz
2.5
Microwave
100 GHz
10-9
Satellite
Optical fiber
2 Gbps
75 THz
10 to 100

4. Twisted pair cable Twisted-Pair
Shielded twisted-pair (STP)
Unshielded twisted-pair (UTP)
Usable frequency spectrum is 1 MHz with 2Mbps to 3Mbps bit rate
Why twisting?

5. Twisted pair cable Categories Cat5 or 5e Cat6 or 6a Cat1 – token ring
Cat2 – 4 Mbps
Cat3 – 10 Mbps at 16 MHz
Cat4 – 16 Mbps at 20 MHz
Cat5 – 10 to 100 Mbps (100BASE-T) at 100 MHz
Cat5e – 1000BASE-T (Gigabit Ethernet)
Cat6 – 10BASE-T/ 100BASE-T/ 1000BASE-T/ 10000BASE-T at 400 MHz
Less cross-talk and system noise by insulating wire pairs
Cat7 – four STP wire pair at 1 MHz to 600 MHz for less cross-talk noise
Ultra Fast Ethernet
Cat5 or 5e Cat6 or 6a

6. Twisted pair cable For higher data rates Shorter repeaters – How?
Advanced modulation scheme – How?
VDSL2 (Very-high-digital-subscriber-Line)

7. Twisted pair cable VDSL2 – >100 Mbps speed
35 MHz over twisted pair cable
Supports triple-paly services - HDTV, VoIP and internet over the same link
Maximum loop length 300m

8. Application PBX, LAN, analog telephone and broadband DSL Analog – POTS
Digital –
ISDN
For high quality transmission over PSTN
BRI – 2B+D (2×64 Kbps + 16 Kbps) up to 5.5km
PRI – 23B+D (23×64 Kbps + 64 Kbps) or 30B+D (30×64 Kbps + 64 Kbps)
xDSL
HDSL/HDSL2 – high-bit-rate DSL (2 Mbps per wire pair up to 3.6 km)
ADSL/ADSL2+ – asymmetrical DSL (7 Mbps/800 Kbps over single wire pair up to 5.5 km)
SDSL – symmetrical DSL (2 Mbps over single wire pair up to 5.5 km )
SHDSL – symmetrical high DSL (up to 5.6 Mbps)
VDSL – very-high-bit-rate DSL (up to 100 Mbps)

9. Coaxial cable Supports 750 MHz to 1000 MHz
Suitable for broadband access
Bus toplogy
Advantages
Braodband
Greater BW and channel capacity
Low error rate
Longer repeater length

10. Microwave Geographical locations where cabling is not cost effective
Example ?
Microwave frequency range – 1 to 100 GHz
35-40 MHz chunk of BW for channels
Frequency α 1 Repeater distance
Line of sight
144 km for Earth curvature
BTRC – 9 KHz to 1000 GHz
Cell phones operate in this frequency range (note the logarithmic scale)

11. Applications Replace the leased line Bypass the legislative procedure
Data domain if interests

12. Microwave frequency bands
More applications
Microwave frequency bands
Designation
Frequency range
Services
L band
1 to 2 GHz
VSAT, Sat, Nav
C band
4 to 8 GHz
Sat, Pow
802.11,
Ku band
12 to 18 GHz
Sat
K band
18 to 26.5 GHz
Ka band
26.5 to 40 GHz
D band
110 to 170 GHz
Communication
Remote sensing
Navigation
Power - ?

13. The new era of Microwave
W-WAN
2G cellular PCS – TDMA, GSM, CDMA
2.5G enhanced data services – GPRS, EDGE, HSCSD
3G high speed data services – WCDMA, UMTS, CDMA2000, TDSCDMA
3.5G IP backbone – HSPDA, HSUPA, HSOPA
4G mobile broadband– OFDM, MIMO
W-MAN
Broadband fixed wireless access
IEEE WiMax, IEEE Mobile-Fi, IEEE Wi-TV
W-LAN
2.4 GHz to 5 GHz IEEE
W-PAN
IEEE Bluetooth, IEEE WiMedia, IEEE ZigBee
RFID

14. Satellite Microwave frequency bands Designation Frequency range
October 4, 1957 Sputnik 1
Footprint – coverage area
Economic benefit α 1 No of Locations
Power requirement α 1 Orbital height
Higher BW α 1 prone to distortions
Supported applications
FSS – fixed satellite services
VSAT
BSS – broadcast satellite services
Portable applications such as advertisement, news van, live streaming
MSS – mobile satellite services (telemedicine, tele surveillance, PDA, vehicular devices)
Microwave frequency bands
Designation
Frequency range
Services
L band
1 to 2 GHz ( MHz)
MSS
C band
4 to 8 GHz (U/L – 6GHz, D/L – 4 GHz)
FSS
Ku band
12 to 18 GHz (U/L –14GHz, D/L – 11 GHz)
FSS, BSS
K band
18 to 26.5 GHz
Ka band
26.5 to 40 GHz
D band
110 to 170 GHz

15. Satellite orbits GEO (Geosynchronous Earth Orbit)
Communication satellites
GPS
36000km above earth
0.25s delay
Broadcast or point-to-multipoint link
MEO (Middle Earth Orbit) – 10,000 to 15,000 km orbital height
Delay is reduced for low height
Smaller footprint – mobile voice and low-speed data
LEO (Low Earth Orbit) – 640m to 1600 km
Smallest footprint (5 times more than MEO and 20 times more than GEO)
About 0.05s delay – call handover for mobile voice, low and high speed data

16. Optical fiber Operates in 1014 Hz to 1015 Hz
Three different wavelength
850, 1300 and 1550 nm
Each band offers 25 THz capacity
Maximum repeater distance
800 km