This document provides an overview of radio communication. It covers topics such as radio and microwave communication, spectrum management, digital microwave systems, fading countermeasures, modulation methods, broadband wireless access, radio frequency identification, intelligent transportation systems, and amateur radio. The key points covered include definitions of radio frequency bands, common applications that use radio frequencies, and concepts related to radio wave propagation, spectrum allocation, and digital microwave link performance.

1. Overview of Radio Communication
OVERVIEW OF RADIO
COMMUNICATION
NTIPRIT
National Telecommunication Institute for Policy Research, Innovation and Training
Ghaziabad – 201002. www.ntiprit.gov.in
Naveen Jakhar, ITS
1

2. Overview of Radio Communication
Topics covered in this Presentation:
1. Radio & Microwave Communication.
2. Spectrum Management.
3. Digital Microwave Systems.
4. Fading and measures to counter Fading effect.
5. Digital Microwave link – Performance
Objectives.
6. Modulation Methods.
7. A word about BWA
8. Other wireless communication Applications
Overview of Radio Communication
2

3. Overview of Radio Communication
PHz = petahertz
Ehz = exahertz
3

4. Overview of Radio Communication
+ Satellite TV+ WiFi, Bluetooth
Cellphones +
+ Satellite TVGPS +
Short-Wave
Broadcast
4

5. Overview of Radio Communication
Radio Waves Propagation
• Ground Waves - < 30 MHZ (Tropospherically Reflected)
• Sky Waves – reflected by ionosphere. Short Waves 30MHz – 40 MHz
( Ionospherically Reflected)
• Space Wave- > 40 MHZ ( >1000 MHZ also know as LOS )
 Ground Waves - suitable for frequencies < 30 M Hz.
Waves travel in troposphere.
• Direct Wave.
• Ground Reflected Wave.
• Tropospherically Reflected Wave.
5

6. Overview of Radio Communication
Propagation Modes
Ground-Wave
6

7. Overview of Radio Communication
Propagation Modes
Direct-Wave
All Frequencies
7

8. Overview of Radio Communication
SATELLITE
REPEATER
10000 KM
1500 KM
750 KM
LOS
MAXIMUM COVERAGE EARTH
TROPOSPHERIC
SCATTER
IONOSPHERIC
REFLECTION
(HF RADIO)
FIG. : MODES OF COMMUNICATION
8

9. Overview of Radio Communication
UHF = Ultra-High Frequency
applications
1000 m
3 GH300 MHz
10 Km
FREQUENCY
WAVELENGTH
2 GHz
UHF TV
1000 MHz
Keyless Entry 315 MHz
Analog Cell Phone
WiFi etc. 2.4 GHz
Digital Cellphone
GPS 1.575 GHz
9

10. Overview of Radio Communication
BLUETOOTH- 2.4 - 2.485 GHZ
WI-FI- 2.4-5.0 GHZ
GPS-: L1 (1575.42 MHz) and L2
(1227.60 MHz)
KEYLESS SYSTEMS-315 MHZ
10

11. Overview of Radio Communication
11
Basic mechanisms that impact propagation
• Reflection: electromagnetic wave impinges upon an object
which has very large dimensions when compared to the
wavelength of the propagation wave.
– Occurs from the surface of the earth, building and walls.
• Diffraction: occurs when the radio path is obstructed by a
surface that has sharp irregularities (edges).
– Secondary waves present throughout the space and even
behind the obstacles, giving rise to a bending of waves
around the obstacles.
• Scattering: occurs when the medium through which the wave
travel consists of objects with dimensions that are small
compared to the wavelength, and where the number to obstacles
per unit volume is large. foliage, atmospheric impurities.

12. Overview of Radio Communication
2.Spectrum Management
12

13. Overview of Radio Communication
 At national level, each administration has its own
regulating agency like NTIA/FCC in USA, Ofcom in UK
and WPC Wing in India.
 WPC- Wireless Planning and Coordination Wing, under
DOT,MOC &IT HQ at Sanchar Bhawan New Delhi.
 Radio spectrum is divided into spectrum bands that are
allocated to specific services, such as mobile, fixed,
broadcast, fixed satellite and mobile satellite services on
exclusive basis.
Spectrum Management
13

14. Overview of Radio Communication
 In India the Wireless Planning & Coordination (WPC) Wing of the
Ministry of Communications & IT, is the National Radio Regulatory
Authority responsible for Frequency Spectrum Management, including
licensing and caters for the needs of all wireless users (Government and
Private) in the country.
 The WPC Wing performs its functions through various divisions /
groups.
 The wireless services is based on National Frequency Allocation Plan
(NFAP) which was made effective from 01.01.2000. The latest one is
Draft NFAP 2011.
 NFAP is the basis for development, manufacturing and spectrum
utilization activities in the country.
Spectrum Management in IndiaSpectrum Management in India
15

15. Overview of Radio Communication
Transmission Systems
Bounded media
(Optical Fiber, coaxial cable)
•Bounded media require a
physical connection between
two points to guide current,
electromagnetic wave or light.
Unbounded media
(UHF, VHF, Microwave
and Satellite)
Unbounded media needs
no such physical
connection .
16

16. Overview of Radio Communication
OF Vs MW Systems
OF Systems
• Very High Bandwidth
• up-to 40 GBps with DWDM
• High Reliability
• OF cable susceptible to cuts
etc.
MW Systems
• Limited Bandwidth due to Radio.
• Max up-to STM-1 systems.
• Less Reliable.
• Quick Deployment
• Suitable for Hilly, inaccessible
and difficult terrain areas.
• Mobile End links
17

17. Overview of Radio Communication
Microwave Systems
1. Unlike Cellular Systems, Microwave systems work on
Line of Sight (LOS) principle.
3. Wideband Microwave Systems operate between stations
that are hundreds of Kms apart with number of Repeaters in
between.
• Station A, Station B.
• Tx and Rx Antenna.
• Hop Distance.
2. Microwave Systems are point to point systems.
18

18. Overview of Radio Communication
Radio Frequency Bands(ITU Designations)
VHF band 30 – 300 MHz
UHF 300 – 3000 MHz
beyond 1000 MHz
LOS communication
SHF 3GHz to 30 GHz
EHF 30 GHz to 300 GHz
VHF-Very High Frequency. UHF-Ultra high freq.
SHF- super high freq. EHF-Extremely High Freq. 19

19. Overview of Radio Communication
 L 1-2 GHz
 S 2-4 GHz
 C 4-8 GHz
 X 8-12 GHz
 Ku 12-18 GHz
 K 18-27 GHz
 Ka 27-40 GHz
 V 40-75 GHz
M/W Frequency Bands
 W 75-110 GHz
20

20. Overview of Radio Communication
Frequency Usage
Some commonly used MW Bands are:
• Police Radios: Country dependent.
• FM Radio: 100 MHz Approx.
• Television: 300 MHz Approx.
• Mobile networks: 450-2000 MHz Approx.
• Trunk Routes 2-100GHz.
 The frequencies used by mobile networks varies according
to the standard being used.
21

21. Overview of Radio Communication
23
Spectrum Bands Identified for various wireless
telecom services (INDIA)
Band Technology
450MHz 2G & 3G
700 MHz Digital Mobile TV
800 MHz 2G & 3G
900MHz 2G
1800MHz 2G
1900MHz 2G & 3G
2010-2025 MHz BWA
2.1 GHz 3G
2.3 GHz BWA
2.5 GHz BWA
3.3 GHz BWA
3.4GHz BWA
2.4-2.4835, 5.15-5.35 & 5.725-5.875 GHz are de-licensed spectrum bands.
23

22. Overview of Radio Communication
Fading - Occurs due to multi-path signals.
Challenges of Radio Transmission
24

23. Overview of Radio Communication
Counter Measures For Fading
• Diversity Techniques
• Space Diversity.
• Frequency Diversity.
• Power Control
• ATPC- Automatic Transmit Power Control
• RTPC-Remote Transmit Power Control
25

24. Overview of Radio Communication
Classification of Radio Transmission Equipment
• Low Capacity • 2 Mbps
• 8 Mbps
UHF(400-700MHz)
2Ghz
• Medium
Capacity
• 34 Mbps 7 & 13 GHz.
• Large
Capacity
• 140 Mbps 4,6 & 11 GHz.
• Mini- Links • up-to 16 E1’s
(34 Mbps)
15 & 18 GHz,.
26

25. Overview of Radio Communication
Commonly Used Digital MW Systems
 Long Haul Systems Make
i) High Capacity 6 Ghz 140 Mb/s Systems Fujitsu, NEC, BEL, ITI
(carrying 1920 voice channels )
Used in Main Trunk Routes
ii) Medium Capacity
7Ghz, 34 Mb/s Fujitsu, NEC, BEL, ITI
Used in thin Routes
 Short Haul Systems
11 Ghz, 140 Mb/s
Used for satellite End Links NEC & Others
13 Ghz, 34 Mb/s Used for junction Networking
27

26. Overview of Radio Communication
Microwave System configuration
Radio equipment required at the terminal :
1. Base Band (BB) Processing equipment.
2. I.F modulation equipment/ De-MOD equipment
3. UP converter/ Down Converter.
4. Power Amplifier
5 Antenna Sub. System.
6 Equalizer
28

27. Overview of Radio Communication
( Base Band
Processing )
B.P.F. P.A.
(FET)
RF
Combiner
Antenna
RF
(6GHz)
140 Mbps
MOD
140
Mbps IF RF
(6GHz)
DEMOD
EQUALIZER
D / C B.P.F. Amplifier
BLOCK SCHEMATC OF A 6-GHZ DIGITAL M/W SYSTEM
IF
( 70MHz)
U / C
( 70MHz)
IF
29

28. Overview of Radio Communication
Lower
Band
Fr in M Hz Upper
Band
Fr in M Hz
1,1x 6460 1’,1’x 6800
2,2x 6500 2’.2’x 6840
3,3x 6540 3’,3’x 6880
4,4x 6580 4’,4’x 6920
5,5x 6620 5’,5’x 6960
6, 6x 6660 6’,6’x 7000
7,7x 6700 7’,7’x 7040
8,8x 6740 8’,8’x 7080
Frequency Plan for 6 G Hz Digital M/W Systems
( 6425-7110 M Hz )
30

29. Overview of Radio Communication
Mini-Link
 Medium Capacity point to point Microwave link of capacity 4-16 E1
links operating in 15, 18, 23 and 38 G Hz bands.
 Small radio unit together with an integrated compact antenna forms
ODU.
35

30. Overview of Radio Communication
Digital ModulationDigital Modulation
Carrier signal: Ac cos (2πfct + φ)
Modulation: m(t)
Modulated signal: Ac (t) cos (2πfc(t) t + φ(t))
Vary Vary Vary
amplitude frequency phase
Variations are discrete!!!!!
∝ m(t); discrete
37

31. Overview of Radio Communication
Digital Modulation Types
1. AMPLITUDE MODULATION
(ASK or OOK)
( Amplitude Shift Keying or On off Keying)
2. FREQUENCY MODULATION
(FREQUENCY SHIFT KEYING- FSK)
3. PHASE MODULATION
(PHASE SHIFT KEYING -PSK)
4 QUADRATURE AMPLITUDE MODULATION (QAM)
38

32. Overview of Radio Communication
 Required RF Bandwidth:
 RF BW = Rs/Rc*(1+α )
 Rs = Symbol Rate.
 Rc= coding rate.
 α = cosine roll-off factor of RRC filter.
 Free Space Path Loss:
 FSL = 32.2 + 20 log (f) + 20 log (d) in db.
 f = frequency in MHz.
 d = distance in kms.
Some Fundamental Formulae
39

33. Overview of Radio Communication
 What is the Required RF Bandwidth to carry 64kbps of data stream,
which is ½ Rate coded and BPSK modulation is used ?
Assume RRC filters with α = 0.25.
Some Fundamental Formulae
What is the change in RF Bandwidth requirement if QPSK
modulation is used instead of BPSK modulation ?
40

34. Overview of Radio Communication
What is ?
• WiMAX or “Worldwide Interoperability for Microwave Access” had its origins in backhaul
connectivity using microwave access.
• WiMAX has become a “hot topic” in the wireless industry, with visible and aggressive
backing from INTEL, among others.
• WiMAX is designed to provide “last-mile” or “backhaul” connectivity using wireless
– “Last-mile” refers to a wireless connection from a major trunk line to a business or residential user
– Using IEEE 802.16 Broadband Wireless Access (BWA) standard, approved in January 2003, to
provide operations in the <11GHz spectrum range
41

35. Overview of Radio Communication
WiMAX Vision: Broadband Everywhere
BWA Operator
Network Backbone
INTERNET
BACKBONE
Mobile
Backhaul
3
RESIDENTIAL & SoHo
DSL LEVEL SERVICE
1
802.16d
FRACTIONAL E1
for SMALL
BUSINESS
E1+ LEVEL SERVICE
ENTERPRISE
BACKHAUL for
HOTSPOTS
2
802.16d
H
H
HH
H
H
H
H
H
WMAN Nomadic Coverage
--> handoff from HOT
SPOTS
4
= wide area
coverage outside of
Hot Spots
Mobility
5802.16e
42

36. Overview of Radio Communication
Other Applications
• RFID
• Intelligent Transport System(ITS)
• Amateur radio (HAM)
43

37. Overview of Radio Communication
RFID OperationsRFID Operations
45

38. Overview of Radio Communication
Technical Parameter Active RFID Passive RID
Tag Power Source Internal to Tag Energy transferred from
Reader via RF
Tag Battery Yes No
Availability of Tag
Power
Continuous Only within the range of
Reader field
Requirement of Signal
Strength from Reader to
Tag
Low High
Available Signal
Strength from Tag to
Reader
High Low
Active and Passive TagsActive and Passive Tags
46

39. Overview of Radio Communication
Radio Frequency Identification Devices (Exemption
from Licensing Requirement) Rules, 2005
• “Use of low power Equipment in the frequency band 865 – 867 MHz for
(RFID) Radio Frequency Identification Devices (Exemption from Licensing
Requirement) Rules, 2005 -rules were published in the Gazette of India, Part
II, Section 3, Sub-Section (i), dated the 11th March, 2005, vide notification
No.168 (E), dated the 11th March, 2005.
• Rule 3. Use of wireless equipment in the band 865 – 867 MHz.-
Notwithstanding anything contained in any law for the time being in force, no
licence shall be required by any person to establish, maintain, work, possess or
deal in Radio Frequency Identification Devices (RFID), on non-interference,
non-protection and non-exclusive basis, in the frequency band 865 – 867
MHz with maximum 1 Watt transmitter power, 4 Watts Effective Radiated
Power and 200 kHz carrier bandwidth.
• Rule 4. In case where any person to whom a licence has been issued under
section 4 of the Act, informs that his licensed system is getting harmful
interference from any other radio communication system exempted under
these rules, the use of such unlicensed Wireless equipment shall be
discontinued forthwith.
49

40. Overview of Radio Communication
Intelligent Transport System(ITS)
• Intelligent transport systems (ITS) are advanced
applications which aim to provide innovative services
relating to different modes of transport and traffic
management and enable various users to be better
informed and make safer, more coordinated, and 'smarter'
use of transport networks.
• ITS are systems in which information and communication
technologies are applied in the field of road transport,
including infrastructure, vehicles and users, and in traffic
management and mobility management, as well as for
interfaces with other modes of transport.
50

41. Overview of Radio Communication
Amateur radio (HAM)
Amateur radio (also called "ham" radio) is the use of
designated radio frequency spectra
• for purposes of private recreation,
• Non commercial exchange of messages,
• Wireless experimentation, self-training, and emergency
communication.
The term "amateur" is used to specify "a duly authorised
person interested in radio-electric practice with a purely
personal aim and without pecuniary interest, and to
differentiate it from commercial broadcasting, public
safety (such as police and fire), or professional two-way
radio services (such as maritime, aviation, taxis, etc.).
53

42. Overview of Radio Communication
Amateur radio (HAM)
The WPC—regulates amateur radio in India.
The WPC assigns call signs, issues amateur radio
licences, conducts exams, allots frequency
spectrum, and monitors the radio waves.
In India, the Amateur radio Society of India (ARSI)
represents amateur radio interests at various
forums.
54

43. Overview of Radio Communication
Thank You !!
55