Unit III & Unit IV PPT

1. EC8004- WIRELESS NETWORKS
UNITIII
3G NETWORKS OVERVIEW
PRESENTED BY,
Mr.P.SATHYARAJ ME,MBA,(PhD).,
ASSISTANT PROFESSOR/ECE
RMK COLLEGE OF ENGINEERING & TECHNOLOGY

4. 1G,2G,3G,4G & 5G

8. UMTS Terrestrial Radio Access Network

9. RNS AND RNC
 The RNS has two main logical elements: Node B and an RNC.
 The RNS is responsible for the radio resources and
transmission /reception in a set of cells. A cell (sector) is one
coverage area served by a broadcast channel.
 An RNC is responsible for the use and allocation of all the radio
resources of the RNS to which it belongs.
 The RNC also handles the user voice and packet data traffic,
performing the actions on the user data streams that are necessary
to access the radio bearers.
 The responsibilities of an RNC are:
 Intra UTRAN handover
 Macro diversity combining/splitting of Iub data
 Frame synchronization
 Radio resource management

10. Responsibilities of RNC & Node B
RNC NODE B
Intra RNC Handover Termination of Iub Interface from RNC
Frame synchronization Radio Channels (Encoding & Decoding)
Radio Resource Management Error Detection on Transport Channels
& Indication to Higher layers
UMTS Radio Link Control Frequency & Time Synchronization

11. Additional Requirements……
 Outer loop power control
 Iu interface user plane setup
 Serving RNS (SRNS) relocation
 Radio resource allocation (allocation of codes, etc.).
 Frame selection/distribution function necessary for soft handover
(functions of UMTS radio interface physical layer)
 UMTS radio link control (RLC) sub layers function execution
 Termination of MAC, RLC, and RRC protocols for transport channels,
 i.e., DCH, DSCH
 Iub’s user plane protocols termination

12. UTRAN (GPRS) NETWORK ARCHITECTURE MODEL

13. UTRAN Logical Interfaces
 In UTRAN protocol structure is designed so that layers and planes are logically
independent of each other.
 The protocol structure contains two main layers, the radio network layer
(RNL) and the transport network layer (TNL).
 In the RNL, all UTRAN-related functions are visible, whereas the TNL deals with
transport technology selected to be used for UTRAN but without any UTRAN-
specific changes.
 A general protocol model for UTRAN interfaces is shown in Figure

14. GENERAL PROTOCOL MODEL FOR
UTRAN INTERFACE

15. UTRAN INTERFACE
 The control plane is used for all UMTS-specific control signaling.
 It includes the application protocol. The application protocol is used for setting up
bearers to the UE.
 User information is carried by the user plane.
 The user plane includes data stream(s), and data bearer(s) for data stream(s).
 Each data stream is characterized by one or more frame protocols specified for that
interface.
 The transport network control plane carries all control signaling within the
transport layer. It does not include radio network layer information.
 It contains access link control application part (ALCAP) required to set up the
transport bearers (data bearers) for the user plane.
 It also includes the signaling bearer needed for the ALCAP.
 The transport plane lies between the control plane and the user plane.
 The addition of the transport plane in UTRAN allows the application protocol in the
radio network control plane to be totally independent of the technology
selected for the data bearer in the user plane.

16. Node B
Node B
RNC
Node B
Node B
RNC
Iu
Iur
UTRAN Logical Architecture
RNS
RNS
UTRAN
Universal Mobile Telecommunications System Terrestrial
Radio Access Network
Two network elements are
present in UTRAN
• RNC – Radio N/W Controller
• Node B
UTRAN is subdivided into individual radio
network systems (RNSs), where each RNS is
controlled by an RNC.
The RNC is connected to a set of Node B
elements, each of which can serve one or
several cells.
Iu
Iub
Iub

19. ⦁ Layers and planes are logically
independent.
⦁ Protocol Architecture
has two main layers:
(i) Radio Network
Layer(RNL)
(ii) Transport
Network Layer(TNL)

20. • Control Plane
• User Plane
•Transport Network
Control Plane
•Transport Network User
Plane

21. ⦁ Control Plane
◦ Used for all UMTS-
specific control signaling
◦ Includes two parts
RANAP (RAN
🞄 Application protocol
application part) in Iu
🞄 RNSAP (RNS
application part) in Iur
🞄 NBAP (Node B application
part) in Iub
🞄 Signaling bearer
🞄 transport the application
protocol messages

22. Application protocol
is used for setting up
bearers to UE, i.e.
•radio access bearer in Iu
•radio link in Iur and Iub

23. ⦁ User Plane
◦ Transport all information sent and
received by the user, such as
🞄 coded voice in a voice call
🞄 packets in an Internet
connection
◦ Includes two parts
🞄 data stream(s)
🞄 data bearer(s) for data
stream(s)

24. CS & PS SERVICES
 The CS domain supports circuit-switched services. Some examples of CS
services are voice and fax.
 The CS domain can also provide intelligent services such as voice mail and free
phone.
 The CS domain connects to PSTN/ISDN networks. The CS domain is expected
to evolve from the existing 2G GSM PLMN.
 The PS domain deals with PS services. Some examples of PS services are
Internet access and multimedia services.
 Since Internet connectivity is provided, all services currently available on the
Internet such as search engines and e-mail are available to mobile users.
 The PS domain connects to IP networks.
 The PS domain is expected to evolve from the GPRS PLMN.

25. Iu INTERFACE
Iu Interface
The UMTS Iu interface is the open logical interface that interconnects one UTRAN to the
UMTS core network (UCN).
 On the UTRAN side the Iu interface is terminated at the RNC, and at the UCN side it is terminated
at U-MSC.
 The Iu interface consists of three different protocol planes
1. Radio Network Control Plane (RNCP ),
2. Transport Network Control Plane (TNCP ), and
3. User plane (UP ).
 The RNCP performs the following functions:
 It carries information for the general control of UTRAN radio network operations.
 It carries information for control of UTRAN in the context of each specific call.
 It carries user call control (CC) and mobility management (MM) signaling messages.
The control plane serves two service domains in the core network, the packet-switched (PS)domain
and circuit-switched (CS) domain

31. ⦁ Used for all control
signaling within transport
layer
⦁ Does not include any radio
network layer information
⦁ Includes ALCAP (Access Link
Control Application Part) protocol
used to set up the transport
bearers (data bearer) for user
plane

32. ⦁ Transport Network
User Plane
◦ data bearer(s) in user
plane
◦ signaling bearer(s) for
application protocol

33. Iu Interface:
◦ an open interface that
divides the system into
radio-specific
UTRAN and CN
◦ handles switching,
routing and service
control
Three protocol planes:
Two service domains:
• Packet-switched domain ( Internet and Multimedia)
• Circuit-switched domain ( Voice and fax )
• Radio Network Control
Plane
 Protocol Stack (RNCP)
• Transport Network
Control Plane Protocol
Stack (TNCP)
• User Plane Protocol Stack
(UP)

35. ⦁ IP based signaling bearer.
⦁ Consists of SS7-MTP3-user Adaptation layer(M3UA),
Simple control transmission protocol( SCTP), IP and
AA5.

37. ⦁ Contains RANAP on top of Signaling System 7(SS7)



protocols.
⦁ Protocol Layers:
signaling connection control part(SCCP)
Message transfer part(MTP3-B)
Signaling Asynchronous transfer mode(ATM) adaptation
layer for network-to-network interface(SAAL-NNI)
• SAAL-NNI is divided into:

 Service-specific connection oriented protocol(SSCOP)
Service-specific coordination function(SSCF)
Signaling
functions
 ATM adaptation layer 5(AAL5)- segmenting data in ATM
cells

38. • Connection between two RNCs and drift RNC
•Connection between one RNC and one Node B of two different
RNCs
• Protocol planes are RNCP,TNCP and UP
• Functions of Iur
 Basic Inter RNC Mobility support
 Dedicated Channel Traffic Support
 Common Channel Traffic Support
 Global resource Management Support

39. • Connection between RNC and Node B
• Protocol planes are RNCP,TNCP and UP
• Protocols are
 NBAP
 DCHFP
 RACHFP
 FACHFP
 ALCAP
 Q.aal2
 SSCP or TCP and IP
 MTP3-B
 SAAL-UNI

41.  CS Entity
Serving GPS support node
(SGSN)
 Gateway GPRS support
node (GGSN)
 Domain Name Server (DNS)
 Dynamic Host Configuration
Protocol (DHCP)
 Packet Charging Gateway
 Firewalls
⦁ PS Entity
⦁ Packet based services
⦁ Contains
⦁ Voice and CS data services
 Contains
 Mobile switching center
 (MSC)
 Gateway MSC ( GMSC )
• Functional areas contain
 entities to support
 PS services
 CS services
 Common to both services

44. Function of 3G – MSC
 Mobility management
 Call management
 Supplementary services
 Voice Coding
 SS7,MAP and RANAP Interfaces
 ATM/AAL2 Connection to UTRAN
 SMS
 VLR functionality
 IN and CAMEL
 Operation, Administration and Maintenance
(OAM)agent
functionality

45. Function of 3G – SGSN
 Mobility management
 Session management
 Iu and Gn MAP Interface
 Subscriber database functionality
 Charging
 ATM/AAL5 Connection to UTRAN
 SMS
 Operation, Administration and Maintenance
(OAM) agent functionality

46. Function of 3G – GGSN
 Maintain the information location at SGSN level
Gateway between UMTS and external data networks
 Gateway – specific access methods to intranet
 Route termination for terminated packets
 User data screening and security
 Charging
 User level address allocation
 Operation, Administration and Maintenance
(OAM)
agent functionality

47. ⦁ To handle the SMS from point to point
⦁ Functions of GMSC
 Reception of short message packet data unit (PDU)
 Interrogation of HLR for routing information
 Forwarding of SMS to MSC or SGSN using routing
information
⦁ Functions of IWMSC
 Reception of short message packet data unit (PDU) from 3G-SGCN or 3G-MSC
 Establishing a link with the addressed service center
 Transferring the Short message PDU to the service center

50. TD-CDMA
• It also referred to as high chip rate (HCR) Time division duplex (TDD) and
UMTS TDD.
• TD-CDMA RAN is well suited for high data traffic both licensed and unlicensed
spectrum.
• TD-CDMA is a robust access method that uses a combination of 3 basic multiple
access schemes – FDMA, TDMA and CDMA.
• Use of TDD access method with TD-CDMA is designed to support asymmetric
traffic.
• Generic TD-CDMA Architecture:
TD-CDMA System

51. UTRAN LOGICAL ARCHITECTURE

53.  This architecture converges voice and data .There are no longer separate Iu-CS and Iu-PS
interface but a single Iu interface that carries all media.(See Figure)
 Within the core network, the interface terminates at the SGSN
 New network elements are call state control function (CSCF), the multimedia resource function
(MRF), the media gateway control function (MGCF), the transport signalling gateway (T-SGW)
and roaming signalling gateway (RSG)
 User equipment is greatly enhanced-support SIP
 SGSN & GGSN supports voice in addition to data services
 MRF is a conference bridging function used for support of features such as multiparty calling
and meet me conference service
 T-SGW provides common channel 7 interworking with standard external networks such as
PSTN.
 Media gateway performs interworking with external networks. MGW is controlled by media
gateway control function (MGCF) control protocol is ITU-T H.248

54. Radio Network:
 TD-CDMA supports both circuit and packet services and is designed primarily to
support the asymmetric characteristics of IP data
 Each radio channel has 15 time slots and in each time slot 16 separate codes
can be transmitted.
Channel structure of TD-CDMA

55.  Uplink and downlink channel allocation can be done by system or the operator
 In order to support both packet and circuit services TD-CDMA use both shared
channels and dedicated channels
 TD-CDMA requires a 5MHz of radio bandwidth to operate a single channel
 TD-CDMA support both packet data (asymmetric) and circuit switched
(Symmetric)
 The time slot for TD- CDMA are not allocated on a dynamic basis
 The specific uplink and downlink transmission alternate on the same radio
frequency channel by allocating time slot to either uplink or downlink
 Two modulation scheme are used : QPSK & 16QAM
 Several coding schemes are used with TD-CDMA including spreading ,
scrambling & channelization code
 Like TD-SCDMA there are control, traffic , FACH and RACH channels

56. Interference Mitigation:
 In a line of sight (LOS) environment multipath reduces the orthogonality
between the codes.
 To improve orthogonality , TD-CDMA uses multiuser detection.
Traffic :
 TD-CDMA system are meant for high data usage area such as urban or WLL
applications. Therefore coverage of a cell is smaller
 The capacity of a TD-CDMA network is limited by the number of carriers , the
time slot allocations for uplink and downlink , the radio environment.
 Throughput 1.5Mbps downlink and 1Mbps uplink
 TD-CDMA system is designed for use in unpaired spectrum and its main
 Advantage is improved efficiency in carrying asymmetric traffic
 Range for cell site sector is 7.5km and can be extended to 29kms
 TD-CDMA data throughput is optimized through efficient on demand
assignment of resources

57. TD-SCDMA
 3G wireless mobile services standard promoted by china not commercially used
Advantages of TDD over FDD networks :
 TDD has no paired frequencies it use the same frequency for uplink & downlink
transmission.
 TDD is suitable for asymmetric uplink and downlink transmission rate.
 Spectral efficiency with asymmetric traffic such as IP.
 Fundamental architecture of a TD-SCDMA wireless system has a set of network
components that are common to all 3G Networks

58.  Only one TD-SCDMA cell is shown, other radio access systems could be
included easily, provided that they interface at the MSC/SGSN (Serving GPRS
support node)
Core Network:
 Release 4 network shown in Figure 3.18 is discussed.
 The traditional MSC is broken into constituent parts and is allowed to be used
in a distributed manner- MSC server and media gateway(MGW).
 MSC server contains all the mobility management and call control logic.
 Control signalling for circuit switched calls is between the radio network
controller(RNC) and the MSC server.
 Media path for circuit switched calls in between the RNC and MGW
 MGW takes call from RNC and routes those call towards their destination over a
packet backbone.

59. RELEASE NETWORK

60.  Control protocol is H.248 – MEGACO
 MSC server contains all the mobility management and call control logic that would
be contain in a standard MSC.
 Packet data traffic from RNC is passed to the SGSN and from SGSN to gateway
GPRS support node (GGSN) over an IP backbone.
Radio Network:
 Supports both circuits – 12.2, 64,144,384 and 2048 kbps
 Packet services – 9.6, 64,144,384, and 2048 kbps
 TDD RAN is unique in that it uses a 1.6MHz wide carrier.
 The radio spectrum can start with as little as 1.6MHz of contiguous spectrum with
guard band 100 to 200kHz
 At present band favoured is 2010 to 2025 MHz band.
 The frame structure is more adaptive
 There are a total of seven time slots for each TD-SCDMA carrier. Each carrier 10ms
length.
 Time slot 0 (TS0) – Broadband channel (BCH), also send downlink information
 TSI –dedicated uplink time slot
 Both time shot 0 and time slot 1 use a forward and reverse pilot .

61.  DWPTS for downlink & UPPTS for uplink – synchronization
 TDD adapts the uplink /downlink format according to the data loads within a
single frequency band
 Total 16 spreading codes are used with TD-SCDMA system.
 There are numerous logical channels in TD- SCDMA System
 Types of channel
a) control channel
b) traffic channel
Common control channel consists of
BCH(Broadcast Channel)- Allocated to at least one radio unit per call or sector
PCH (Paging Channel)- Special broadcast channel used for paging
Forward access channel (FACH) is used to respond to a UE’S random access
request and is paired with the Random access channel (RACH)

62. Interference Mitigation :
TD-SCDMA was a combination of interference mitigation technique
• Smart antenna :
Array of multiple antennas elements & coherent transceivers
Dynamically generate multiple beam patterns to reduce co-channel interference
• Joint Detection :
To estimate the radio channel and work for all signals simultaneously .
Through parallel processing it eliminates multiple access interference and minimizes intra cell
interference.
• Terminal synchronization :
Accurately tune the transmission timing of each individual terminal uplink.
• Dynamic channel allocation :
Able to allocate radio resources in an adaptive fashion to minimize the interference
• Traffic :
The throughputs for data with TD-SCMDA is decided by
a) The transmit power and reception sensitivity
b) Length of guard period
With TD- SCDMA there is no soft handoff. This concept free up resource at surrounding sites,
enabling more capacity

63. Channel structure for a TD-SCDMA
carrier is shown in Fig

64. UNIT 4
INTERNETWORKING BETWEEN WLANS AND WWANS
 Wireless local area networks (WLANs) are subjected to interference because of their operation in the unlicensed spectrum.
WLANs’ coverage ranges from about 30 to 300m.
 WLANs can cover only a small area and allow limited mobility, but provide higher data rates. Therefore, WLANs are well suited
to hotspot coverage where there is a high density of demand for high-data-rate wireless services requiring limited mobility.
 On the other hand, 3G wireless networks, with their well-established voice support, wide coverage, and high mobility, are more
suited to areas with moderate or low-density demand for wireless usage requiring high mobility.
 Therefore, WLANs and 3G are complementary.
 The integration of 3G wireless and WLANs is highly significant to make wireless multimedia
and other high-data-rate services a reality for a large population.
 A multimedia 3G/WLAN terminal can access high bandwidth data services where WLAN
coverage is offered, while accessing wide area networks using 3G at other places.
 However, this approach alone will only allow limited multi-access functionality.
 To make multi-access solutions effective, we need an integrated solution to provide
seamless mobility between access technologies, allowing continuity of existing sessions.
 3G/WLAN integration promises to offer these capabilities seamlessly subscribers in a WLAN
environment.

65. INTERWORKING OBJECTIVES AND REQUIREMENTS
 One of the principal objectives of interworking is to allow independent evolution of 3GPP (WWAN) and WLAN
standards.
 The extent of interdependence between these standards should be minimized or
localized at the point of interconnection.
 Support for the legacy WLAN user is perhaps the most important objective of a
3GPP-WLAN interworking setup. A legacy WLAN user is a user with a WLAN-capable
device and a subscription to 3GPP services.
 The user may or may not be 3GPP capable. Such a user should be able to access
3GPP services without substantial hardware/software upgrades.
 Such a setup would result in a strong business case, leading to extend the facility of
3GPP services to the user who, although having a 3GPP subscription, does not want
to spend it on additional hardware/software upgrades.

66.  The following are the interworking requirements:
1. Common billing and customer care:
 This is the simplest form of interworking that provides a common bill and customer care to the
subscriber but otherwise requires no real interworking between the WLAN and 3GPP data
networks.
2. 3GPP-based access control and charging:
 This requires authentication, authorization, and accounting (AAA) for subscribers in the WLAN to
be based on the same AAA procedures used in the 3GPP data networks. It means a mobile
subscriber can use his or her subscriber identity module/ UMTS-SIM (SIM/USIM) to access WLAN
services.
3. Access to 3GPP-based packet switched services:
 The aim of this requirement is to allow the mobile operator to allow access to its 3GPP data
services to subscribers in a WLAN environment.
 It means a mobile subscriber should be able to access/select 3GPP data services through the
WLAN access network.
 Although the user is allowed access to the same 3GPP data services over both the 3GPP and
WLAN access networks, no service continuity across these access networks is required in this
scenario.
4. Service continuity:
 The goal is to allow seamless service continuity across the 3GPP and WLAN systems. It means
that a user session during mobility across these networks should not only continue but also
should not have noticeable service change in terms of quality and disruption.
5. Access to 3GPP circuit-switched services:
 The goal of this requirement is to allow the 3GPP operator to offer access to circuit-switched
services such as voice calls from the WLAN systems.
 Seamless service continuity is a must for these services.

67. SCHEMES TO CONNECT WLANS AND 3G NETWORKS
 Basically, interworking schemes can be categorized as
 Mobile IP Approach
 Gateway Approach
 Emulator Approach

68. Mobile IP Approach (called loose coupling approach)
This introduces mobile IP to two networks.
 Mobile IP mechanisms can be implemented in the mobile nodes and installed on the network devices
of 3G and WLANs.
 This approach provides IP mobility for roaming between 3G and WLANs.
 However, this approach requires installing mobile IP devices such as a home agent (HA) and a foreign
agent (FA) in both networks, and terminal devices should also implement mobile IP features.
 Since the user device requires sending the registration back to its home network, packet delay and
loss are also a problem for handoffs.
 Moreover, this approach suffers from the triangular routing between networks if mobile IP does not
support route optimization

69. Gateway approach
This introduces a new logical node to connect two wireless networks.
 The new node is located between the two networks and acts as an internal device.
 It exchanges necessary information between the two networks, converts signals, and forwards the
packets for the roaming users.
 This approach aims to separate the operations of two networks, which implies the two networks are
peer-to-peer networks and can handle their subscriber independently.
 With the two network operators having a roaming agreement, the logical node helps two networks
offer intersystem roaming.
 The advantages of this approach are that the two networks can be operated independently; packets
for roaming users go through the node without processing by mobile IP; and handoff delay and loss
can be reduced

70. Emulator approach (called tight coupling approach)
This approach uses WLAN as an access stratum in a 3G network.
 This approach replaces 3G access stratum by WLAN layer one and layer two.
 A WLAN access point (AP) can be viewed as a 3G network controller or a serving GPRS support node
(SGSN).
 The benefit of this approach is that mobile IP is not required. All packet routing and forwarding are
processed by a 3GPP core network. The packet loss and delay can be reduced significantly.
 However, this approach lacks flexibility since two networks are tightly coupled. The operators of two
networks should be the same in order to exchange much information.
 Another disadvantage of this approach is that the gateway GPRS support node (GGSN) will be the
single point to the Internet. All packets have to go through the GGSN first.
 GGSN and the core network become the bottleneck