1. UNIT-III
MOBILE COMMERCE
WIRELESS COMMUNICATIONS TECHNOLOGY : Wireless wide area
network (WWAN) technology: cellular systems 2G (CDMA, TDMA, GSM),
2.5G (GPRS, EDGE), 3G (WCDMA/UMTS, CDMA2000), 4G. Wireless local
area network (WLAN) technology (wi-fi), Wireless metropolitan area
network (WMAN) technology (wi-max) Wireless personal area network
(WPAN) technology (Bluetooth).

2. Wireless Communication
• Wireless communication involves the transmission of
information over a distance without the help of wires, cables or
any other forms of electrical conductors.
• Wireless communication is a broad term that incorporates all
procedures and forms of connecting and communicating
between two or more devices
• It uses a wireless signal through wireless communication
technologies and devices.
• In wireless communication,data transmission between sender
and receiver is carried out using radio wave /microwave.

3. • The transmitted distance can be anywhere between a few
meters (for example, a television's remote control) and
thousands of kilometers (for example, radio communication).
• Wireless communication can be used for cellular telephony,
wireless access to the internet, wireless home networking, and
so on.

4. Advantages of Wireless Communication:
• There are following advantages of mobile communication:
• Flexibility: Wireless communication enables the people to communicate
with each other regardless of location. There is no need to be in an office
or some telephone booth in order to pass and receive messages.
• Cost effectiveness: In wireless communication, there is no need of any
physical infrastructure (Wires or cables) or maintenance practice. Hence,
the cost is reduced.
• Speed: Improvements can also be seen in speed. The network
connectivity or the accessibility was much improved in accuracy and
speed.
• Accessibility: With the help of wireless technology easy accessibility to
the remote areas is possible. For example, in rural areas, online education
is now possible. Educators or students no longer need to travel to far-flung
areas to teach their lessons.
• Constant connectivity: Constant connectivity ensures that people can
respond to emergencies relatively quickly. For example, a wireless device
like mobile can ensure you a constant connectivity though you move from
place to place or while you travel, whereas a wired landline can't.

5. Modes of wireless communication
1.Broadcast Radio
• The most famous form of wireless transmission on our list, broadcast radio, was probably the first
kind of wireless communication.
• Radio transmitters send out data in the form of radio waves to receiving antennae. Radio waves are
forms of electromagnetic signals.
• Signals are relatively narrow, and waves can be sent across various frequencies.
• This is why your car radio is able to receive signals from many different radio stations.
• There are many types of users of radio communication. Radio stations that send out informative and
entertaining programs
2. Microwave Communication
• Microwave technology is an effective type of communication that is used globally. This technology
can be broken down into 2 types
• Satellite Microwave Communication
• This is the most effective method of transmitting microwaves globally. Like Infrared technologies,
Microwave technologies require a clear line of sight. This means that if you want to send a signal
over a long distance, sending it up to a satellite first is a good idea.
• The only problem is that in very dense cloudy weather the signal to the satellite can be blocked by
atmospherics.

6. 3.Wi-Fi
• Wi-Fi internet is a low powered wireless electronic network.
• These are available in almost every shopping mall and cafe
in the world.
• Essentially a physical wired network is connected to a
router. This creates a highly localized and low power
wireless network.
• From this, it is possible to connect a range of devices to
the local network.
• However, public wireless internet access is known to be a
target for thieves and hackers.
• Therefore, it is essential that both users who connect to
these networks and the providers use password protection
defense methods.
4. Mobile Communication Systems
• The burgeoning mobile phone industry uses similar technology
to Wi-Fi but on a much grander and safer scale.
• Mobile phone companies provide coverage to customers
nationwide or even international scale.
• They do this by means of a complex blend of local networks
and transmitters together with satellite support.

7. 5.Bluetooth Technology
• Bluetooth is a relatively new technology but is
becoming more and more prevalent.
• It is essentially a simple method to send
information across a short distance.
• However, this information can include either
messages or even files.
• Bluetooth technology was originally designed to
be a replacement for physical cables.
• It has a maximum reach of 30 feet.

8. WWAN Technologies:
• WWAN : WWAN (Wireless Wide Area Network) is a WAN (Wide
Area Network) and the only thing is that the connectivity is
wireless.
• It provides regional, nationwide and global wireless coverage.
• Where Wide Area Network can be wired or wireless the
Wireless Wide Area Network connections are completely
wireless.
• WWAN uses telecommunication cellular network technologies
such as 2G, 3G, 4G LTE, and 5G to transfer data.

10. Characteristics :
•Seamless operation.
•Low power for battery use.
•Simple management, easy to use for everyone.
•Protection of investment in wired networks.
•Robust transmission technology
Advantages :
•Installation speed and simplicity.
•Installation flexibility.
•Reduced cost of ownership.
•Reliability.
•Mobility.
•Robustness.
Disadvantages :
•Slower bandwidth.
•Security for wireless LAN’s is the prime concern.
•Less capacity.
•Wireless networks cost four times more than wired network cards.
•Wireless devices emit low levels of RF which can be harmful to our
health.

11. Cellular system
• Early wireless systems had a high-power transmitter, covering
the entire service area.
• This required a very huge amount of power and was not
suitable for many practical reasons.
• The cellular system replaced a large zone with a number of
smaller hexagonal cells with a single BS (base station) covering
a fraction of the area.
• Evolution of such a cellular system is shown in the given
figures, with all wireless receivers located in a cell being served
by a BS.

13. • Several mobile switching centers are interconnected to a PSTN
(public switched telephone network) and the ATM
(asynchronous transfer mode) backbone.
• To provide a better perspective of wireless communication
technology, simplified system infrastructure for cellular system
is shown in the figure:

14. Cellular technology networks
• Simply, the "G" stands for "GENERATION". While connected to the
internet, the speed of the connection depends upon the signal
strength that is shown in abbreviations like 2G, 3G, 4G, 5G, etc.
• on any mobile device. Each generation of wireless broadband is
defined as a set of telephone network standards that describe the
technological implementation of the system.
• The aim of wireless communication is to provide high quality, reliable
communication just like wired communication and each new
generation represents a big leap in that direction.
• Mobile communication has become more popular in the last few
years due to fast reform in mobile technology.

15. 2G
• 2G is short notation for second-generation cellular network, a group
of technology standards employed for Cellular networks.
• 2G was commercially launched on the GSM standard in 1991.
• The radio signals used by the 1G network were analog, while 2G
networks were digital.
• 2G capabilities were achieved by allowing multiple users on a single
channel via multiplexing.
• During 2G, cellular phones were used for data along with voice.

16. • Some of the key features of 2G were:
Data speeds of up to 64 kbps
Use of digital signals instead of analog
Enabled services such as SMS and MMS (Multimedia Message)
Provided better quality voice calls
It used a bandwidth of 30 to 200 KHz
Some major examples of 2G systems are CDMA,TDMA and GSM

17. CDMA
• Code Division Multiple Access (CDMA) is a channel access
method normally used by 2G &3G radio communication
technology as well as in some other technologies.
• Code Division Multiple Access (CDMA) is a digital cellular
technology used for mobile communication.
• It generates communication with help of digital bits.

18. TDMA
• Time Division Multiple Access (TDMA) is a digital cellular
telephone communication technology.
• It facilitates many users to share the same frequency without
interference.
• Its technology divides a signal into different timeslots, and
increases the data carrying capacity.
• Time Division Multiple Access (TDMA) is a complex technology,
because it requires an accurate synchronization between the
transmitter and the receiver.
• TDMA is used in digital mobile radio systems.

19. Advantages of TDMA
• Here is a list of few notable advantages of TDMA −
• Permits flexible rates (i.e. several slots can be assigned to a user,
for example, each time interval translates 32Kbps, a user is
assigned two 64 Kbps slots per frame).
• Can withstand gusty or variable bit rate traffic(variablr speed).
• No guard band required for the wideband system.
• No narrowband filter required for the wideband system.

20. GSM
• GSM stands for Global System for Mobile Communication.
• It is a digital cellular technology used for transmitting mobile
voice and data services.
• The concept of GSM emerged from a cell-based mobile radio
system at Bell Laboratories in the early 1970s.
• GSM is the name of a standardization group established in 1982
to create a common European mobile telephone standard.
• GSM is the most widely accepted standard in
telecommunications and it is implemented globally.

21. • GSM owns a market share of more than 70 percent of the
world's digital cellular subscribers.
• GSM makes use of narrowband Time Division Multiple Access
(TDMA) technique for transmitting signals.
• GSM was developed using digital technology. It has an ability to
carry 64 kbps to 120 Mbps of data rates.
• Presently GSM supports more than one billion mobile
subscribers in more than 210 countries throughout the world.
• GSM provides basic to advanced voice and data services
including roaming service.

22. 2.5G
• When GPRS technology was introduced, it enabled web
browsing, e-mail services and fast upload/download speeds.
• 2G with GPRS is also referred as 2.5G, a step short of next
mobile generation.
• 2.5G Technology (which stands for “second and a
half generation”) is a cellular wireless
technology developed in between its
predecessor, 2G, and its successor, 3G.
• Some major examples of 2.5 networks are
EDGE(enhanced data GSM environment) &
GPRS(general pocket radio service)

23. GPRS
• General Packet Radio System is also known as GPRS is a third-
generation step toward internet access.
• GPRS is also known as GSM-IP that is a Global-System Mobile
Communications Internet Protocol as it keeps the users of this system
online, allows to make voice calls, and access internet on-the-go.
• GPRS is the first step toward an end-to-end wireless infrastructure and has
the following goals:
Open architecture
Consistent IP services
Same infrastructure for different air interfaces
Integrated telephony and Internet infrastructure
Leverage industry investment in IP
Service innovation independent of infrastructure

24. EDGE
• EDGE (Enhanced Data Rate For GSM Evolution) provides a
higher rate of data transmission than normal GSM.
• It uses a backward-compatible extension of GSM of digital
mobile technology.
• It can work on any network deployed with GPRS (with
necessary upgrades).
• In order to increase data transmission speed, EDGE was
deployed on the GSM network in 2003 by Cingular in the USA.

25. Features:
It provides an evolutionary migration path from GPRS to UMTS.
It is standardized by 3GPP.
EDGE is used for any packet switched application,like an Internet
connection.
EDGE delivers higher bit-rates per radio channel and it increase the
capacity and performance.
Advantage:
It has higher speed.
It is an “always-on” connection
It is more reliable and efficient
It is cost efficient
Disadvantage:
It consumes more battery.
hardware needs upgradation.

26. 3G
• Third generation mobile phones, or “3G Internet” mobile
phones, is a set of standards for wireless mobile communication
systems, that promises to deliver quality multimedia services
along with high quality voice transmission.
• Two main specifications under this are −
Wideband CDMA (WCDMA)
CDMA2000

27. Features:
• 3G systems comply with the International Mobile
Telecommunications-2000 (IMT-2000)
• specifications by the International Telecommunication Union
(ITU).
• The first 3G services were available in 1998.
• It provides high speed transmission having data transfer rate
more than 0.2Mbps.
• Global roaming services are available for both voice and data.
• It offers advanced multimedia access like playing music, viewing
videos, television services etc.

28. WCDMA/UMTS
• The WCDMA(Wideband Code Division MultipleAccess)system is
part of the UMTS(Universal Mobile Telecommunication System.
• It is developed by the 3G Partnership Program, which is
composed of evolved core cellular networks that belong to the
Global System for Mobile (GSM) communications networks
worldwide.

29. • WCDMA features two modes:
• Frequency Division Duplex (FDD): Separates users by employing
both codes as well as frequencies. One frequency is used for the
uplink, while another is used for the downlink.
• Time Division Duplex (TDD): Separates users by employing
codes, frequencies and time, wherein the same frequency is
used for both uplink and downlink.

30. CDMA2000
• CDMA2000 is a code division multiple access (CDMA) version of
IMT-2000 specifications developed by International
Telecommunication Union (ITU).
• It includes a group of standards for voice and data services −
• Voice − CDMA2000 1xRTT, 1X Advanced
• Data − CDMA2000 1xEV-DO (Evolution-Data Optimized)

31. Features
• CDMA2000 is a family of technology for 3G mobile cellular
communications for transmission of voice, data and signals.
• It supports mobile communications at speeds between 144Kbps
and 2Mbps.
• It has packet core network (PCN) for high speed secured
delivery of data packets.
• It applies multicarrier modulation techniques to 3G networks.
This gives higher data rate, greater bandwidth and better voice
quality.
• It has multi-mode, multi-band roaming features.

32. 4G
• Fourth Generation (4G) mobile phones provides broadband
cellular network services and is successor to 3G mobile
networks.
• It provides an all IP based cellular communications.
• The capabilities provided adhere to IMT-Advanced
specifications as laid down by International Telecommunication
Union (ITU).

33. Features:
• It provides an all IP packet switched network for transmission of
voice, data, signals and multimedia.
• It aims to provide high quality uninterrupted services to any
location at any time.
• As laid down in IMT-Advanced specifications, 4G networks
should have peak data rates of 100Mbps for highly mobile
stations like train, car etc., and 1Gbps for low mobility stations
like residence etc.
• It also lays down that 4G networks should make it possible for 1
Gbps downlink over less than 67 MHz bandwidth.
• They provide have smooth handoffs across heterogeneous
network areas.

34. Types of 4G
• 4G comes in two main categories −

35. LTE
• Long – term evolution or LTE is an extension of the 3G
technology.
• It is a standard for high-speed mobile communication, based
upon GSM/EDGE and UMTS/HSPA technologies.
• The peak data rate for download is 100 Mbps and upload is 50
Mbps.
• The LTE Advanced meets the specifications of IMT-Advanced
standard for 4G technology.
• Its peak data rates are 1000 Mbps for downlink and 500 Mbps
for uplink.

36. Worldwide Interoperability for Microwave Access (WIMAX)
• WiMAX is a mobile wireless broadband access (MWBA) standard
is sometimes branded 4G.
• It offers peak data rates of 128 Mbps for downlink and 56 Mbps
for uplink over 20 MHz wide channels.
• The latest version of WIMAX is not compatible to the earlier
versions and instead is compatible with LTE.

37. Wireless LAN Technologies:
• Wireless LANs (WLANs) are wireless computer networks that use
high-frequency radio waves instead of cables for connecting the
devices within a limited area forming LAN (Local Area Network).
• Users connected by wireless LANs can move around within this
limited area such as home, school, campus, office building,
railway platform, etc.
• Most WLANs are based upon the standard IEEE 802.11 standard
or WiFi.

38. Advantages of WLANs
• They provide clutter-free homes, offices and other networked places.
• The LANs are scalable in nature, i.e. devices may be added or
removed from the network at greater ease than wired LANs.
• The system is portable within the network coverage. Access to the
network is not bounded by the length of the cables.
• Installation and setup are much easier than wired counterparts.
• The equipment and setup costs are reduced.
Disadvantages of WLANs
• Since radio waves are used for communications, the signals are
noisier with more interference from nearby systems.
• Greater care is needed for encrypting information. Also, they are
more prone to errors. So, they require greater bandwidth than the
wired LANs.
• WLANs are slower than wired LANs.

39. WIFI
• WiFi stands for Wireless Fidelity.
• WiFiIt is based on the IEEE 802.11 family of standards and is
primarily a local area networking (LAN) technology designed to
provide in-building broadband coverage.
• Current WiFi systems support a peak physical-layer data rate of
54 Mbps and typically provide indoor coverage over a distance
of 100 feet.
• WiFi has become the de facto standard for last mile broadband
connectivity in homes, offices, and public hotspot locations.
Systems can typically provide a coverage range of only about
1,000 feet from the access point.

40. Advantages of Wifi
• Convenience
• Mobility
• Productivity
• Deployment
• Expandability
• Cost
Disadvantages of Wifi
• Security
• Range
• Reliability
• Speed

41. Wireless Personal Area Network(WPAN)
• A wireless personal area network (WPAN) is a type of
personal network that uses wireless communication
technologies to communicate and transfer data between the
user’s connected devices.
• It allows an individual to connect all or most of his or her
devices together and access the Internet or a local network
using any of the native/supported wireless communication
techniques.
• WPAN is also known as a short wireless distance network.
• Typically, the devices in WPAN include peripheral and hand-
held devices such as PDAs, smart phones and tablet PCs.

42. Bluetooth
• Bluetooth wireless technology is a short range communications
technology intended to replace the cables connecting portable unit
and maintaining high levels of security.
• Bluetooth specification details the entire protocol stack. Bluetooth
employs Radio Frequency (RF) for communication.
• It makes use of frequency modulation to generate radio waves in
the ISM band.
• Bluetooth offers a uniform structure for a wide range of devices to
connect and communicate with each other.
• Bluetooth technology has achieved global acceptance such that any
Bluetooth enabled device, almost everywhere in the world, can be
connected with Bluetooth enabled devices.

43. • Low power consumption of Bluetooth technology and an
offered range of up to ten meters has paved the way for several
usage models.
• Bluetooth offers interactive conference by establishing an adhoc
network of laptops.
• Bluetooth usage model includes cordless computer, intercom,
cordless phone and mobile phones.