Migrating from GPRS to UMTS

From GPRS network, the following network elements can be reused:

• Home Location Register (HLR)
• Visitor Location Register (VLR)
• Equipment Identity Register (EIR)
• Mobile Switching Center (MSC) (vendor dependent)
• Authentication Center (AUC)
• Serving GPRS Support Node (SGSN) (vendor dependent)
• Gateway GPRS Support Node (GGSN)

From Global Service for Mobile (GSM) communication radio network, the following elements cannot be reused

• Base station controller (BSC)
• Base transceiver station (BTS)

They can remain in the network and be used in dual network operation where 2G and 3G networks co-exist while network migration and new 3G terminals become available for use in the network.

The UMTS network introduces new network elements that function as specified by 3GPP:

• Node B (base station)
• Radio Network Controller (RNC)
• Media Gateway (MGW)

The functionality of MSC and SGSN changes when going to UMTS. In a GSM system the MSC handles all the circuit switched operations like connecting A- and B-subscriber through the network. SGSN handles all the packet switched operations and transfers all the data in the network. In UMTS the Media gateway (MGW) take care of all data transfer in both circuit and packet switched networks. MSC and SGSN control MGW operations. The nodes are renamed to MSC-server and GSN-server.

WCDMA (UMTS) Chipset Solutions

Overview

QCT has emerged as a leader in WCDMA (UMTS) technology with industry-leading solutions delivering significant time-to-market advantages. Continually raising the bar in technological innovations, QCT works closely with the entire wireless ecosystem to bring the benefits of UMTS to consumers around the world.
QCT began its work in the UMTS market with innovative solutions for WCDMA. It then led the industry with the first HSDPA, HSUPA and HSPA+ chipsets on the market. These technologies enable new and advanced applications, allowing operators to differentiate their service offerings and empowering device manufacturers to develop compelling next generation devices. Users can experience the best that wireless has to offer.
QCT is also committed to pushing these advanced wireless capabilities to all market tiers by making it easier for operators to roll out services and expand coverage areas. The QSC family of integrated single-chip solutions is an example of that, bringing cost and time-to-market advantages that have spurred growth in wireless broadband and 3G adoption in mass markets across the globe.

Benefits

High-speed data services.
QCT's WCDMA technology and its extensions, such as HSPA and HSPA+, provide broadband data rates to enable feature-rich applications such as multimedia streaming, photo sharing, location-based services, 3D graphics, multiplayer gaming, and social networking capabilities.
Single-source, cost-effective solutions.
QCT's WCDMA chipset solutions integrate high-performance technologies, such as advanced multimedia, peripheral connectivity, user interface frameworks, storage and Assisted-GPS solutions. Our integrated designs eliminate the need for separate multimedia companion processors and memory subsystems, so manufacturers can reduce costs and time to market, while developing smaller devices with increased functionality.
A proven track record.
QCT's WCDMA solutions are built on established CDMA experience. We deliver fully tested, completely integrated technologies supported by our expert team of engineers. QCT products are designed from the ground up to help operators minimize development costs and optimize product performance.
Driving advanced wireless technology adoption.
QCT is committed to ensuring more wireless users across the globe can access the most advanced mobile technologies. QCT's close relationships with all our partners-from OEMs and developers to carriers and operators-underscore that commitment. We work hard to create integrated, efficient solutions that reduce manufacturing time and costs while accelerating the migration of 2G users to 3G and then to more advanced technologies.

Qualcomm and Huawei to Cooperate on Advanced UMTS Node B Receiver Technology

Qualcomm Incorporated, a leading developer and innovator of Code Division Multiple Access (CDMA) and other advanced wireless technologies, and Huawei Technologies, a leader in providing next generation telecommunications network solutions for operators around the world, today announced the signing of a technology transfer agreement for advanced Node B (base station) receiver design that can benefit all UMTS systems, Release 99 and onwards. For example, the agreement covers new technology that can boost the data throughput performance of High Speed Uplink Packet Access (HSUPA) networks by up to 60 percent. Technology transferred by Qualcomm under this agreement will enable Huawei to deploy highly advanced 3G networks in markets using any UMTS-based technologies.
The key feature of this technology is Uplink Interference Cancellation, a component of advanced receiver designs for Node B technology. Uplink Interference Cancellation uses baseband processing to eliminate interference that can arise from multiple uplink data streams in a cell as well as from neighboring cells. For 2msec transmission time intervals (TTIs), Uplink Interference Cancellation can increase total HSUPA cell throughput by up to 60 percent, with median user data rate improvements of approximately 65 percent. Simulations suggest that systems with this feature can also support up to a 46 percent increase in cell VoIP traffic over an HSUPA Release 7 system and a 200 percent increase over Release 99 systems. This creates a better experience for the growing number of people using mobile devices to upload and share data-intensive photographs and videos, as well as to access popular Voice-over-IP (VoIP) services.
"Qualcomm and Huawei have a close relationship," said Jing Wang, executive vice president of Qualcomm. "We're pleased to have this opportunity to jointly demonstrate UMTS' strong upgrade path and bring improved capacity and new opportunities to global customers."
"Last year, Huawei won 44 commercial contracts to deploy UMTS/HSPA solutions. One of the success factors in gaining such a high level of trust from the world's top operators is our ability to consistently deliver outstanding network performance through the joint development of world-class wireless technologies with industry leaders," said Yu Chengdong, president of Huawei's Wireless Network BU. "We are working closely with Qualcomm to bring more cutting-edge capabilities and products to mobile communications operators and customers all around the world."

Virtual Home Environment (VHE)

Virtual Home Environment (VHE) is a concept for Personal Service Environment (PSE) portability across network boundaries and between terminals. The concept of VHE is such that users are consistently presented with the same personalised features, User Interface customisation and services in whatever network and whatever terminal (within the capabilities of the terminal and the network), wherever the user may be located. For Release 5, CAMEL, MExE, OSA and USAT are considered the mechanisms supporting the VHE concept.

CAMEL Customised Application For Mobile Network Enhanced Logic
MExE Mobile Execution Environment
MRF Media Resource Function
OSA Open Service Access
USAT Universal SIM Application Tool-Kit

A user's VHE is enabled by user profiles as logically depicted in a picture below. The home environment shall:

enable the user to manage one or more user profiles (e.g. activate, modify, deactivate etc.) enable the home environment and HE-VASP to manage one or more user profiles (e.g. activate, modify, deactivate etc.) enable the identification of a user's personalised data and services information directly or indirectly from the user's profile(s) enable authorised HE-VASPs to access the user's profile(s) enable VASPs controlled and limited access to the user's profile(s) (e.g. for general user preferences and subscribed services information). The home environment's view of the Virtual Home Environment concept is logically depicted in a picture below. The home environment shall: be able to provide and control services to the user in a consistent manner also if the user is roaming provide the necessary means to create and maintain a set of user profiles Support the execution of services – through its Service Toolkits in the network, the USIM and in the ME uniquely identify the user in the telecommunication networks supported by the Home Environment. Logical VHE Role Model (Operator's Home Environment's View) The Open Service Access consists of three parts: Applications: e.g. VPN, conferencing, location based applications. These applications are implemented in one or more Application Servers; Framework: providing applications with basic mechanisms that enable them to make use of the service capabilities in the network. Examples of framework functions are Authentication and Discovery. The discovery function enables the application to find out which network service capability features are provided by the Service Capability Servers. Service Capability Servers: providing the applications with service capability features, which are abstractions from underlying network functionality. Examples of service capability features offered by the Service Capability Servers are Call Control and User Location. Mobile Execution Environment (MExE) provides a standardised execution environment in an UE, and an ability to negotiate its supported capabilities with a MExE service provider, allowing applications to be developed independently of any UE platform. The UE (consisting of the ME and SIM/USIM) can then be targeted at a range of implementations for MExE from small devices with low bandwidth, limited displays, low processor speeds, limited memory, MMI etc., to sophisticated with a complete MExE execution environment. Generic MExE architecture Universal Subscriber identity module Application Toolkit (USAT) provides a standardised execution environment for applications stored on the USIM/SIM card and the ability to utilize certain functions of the supporting mobile equipment. SAT/USAT provides mechanisms which allow applications, existing in the USIM/SIM, to interact and operate with any ME which supports the specified mechanism(s) thus ensuring interoperability between a USIM/SIM and an ME, independent of the respective manufacturers and operators. A transport mechanism is provided enabling applications to be down-loaded and/or updated. USAT Diagram

UTRAN Iub Interface General Frame Structure

The general structure of a Common Transport Channel frame between Node B and RNC consists of a header and a payload.

Header

Payload: Data or Control Information

General Frame Structure

There are two types of frames (indicated by the Frame Type field).

Data frame. Control frame. The general structure of frames Data frame example: DL FDD DSCH data frame structure CRC FT CFN TFI SF SP MC Info TB Cyclic Redundancy Checksum Frame Type Connection Frame Number Transport Format Indicator Spreading Factor Spare Multi Code to indicate the number of parallel PDSCH codes on which the DSCH data will be carried Transport Block Control frame example: Iub Common Transport Channel Control Frame Format

UMTS Power Control

Open loop power control is the ability of the UE transmitter to sets its output power to a specific value. It is used for setting initial uplink and downlink transmission powers when a UE is accessing the network. The open loop power control tolerance is ± 9 dB (normal conditions) or ± 12 dB (extreme conditions)

Inner loop power control (also called fast closed loop power control) in the uplink is the ability of the UE transmitter to adjust its output power in accordance with one or more Transmit Power Control (TPC) commands received in the downlink, in order to keep the received uplink Signal-to-Interference Ratio (SIR) at a given SIR target. The UE transmitter is capable of changing the output power with a step size of 1, 2 and 3 dB, in the slot immediately after the TPC_cmd can be derived. Inner loop power control frequency is 1500Hz.

The serving cells estimate SIR of the received uplink DPCH, generate TPC commands (TPC_cmd) and transmit the commands once per slot according to the following rule: if SIR_est > SIR_target then the TPC command to transmit is "0", while if SIR_est < SIR_target then the TPC command to transmit is "1". Upon reception of one or more TPC commands in a slot, the UE derives a single TPC command for each slot, combining multiple TPC commands if more than one is received in a slot. Two algorithms are supported by the UE for deriving a TPC_cmd. Which of these two algorithms is used, is determined by a UE-specific higher-layer parameter, "PowerControlAlgorithm".

Algorithm 1:

The power control step is the change in the UE transmitter output power in response to a single TPC command Algorithm 2: If all five estimated TPC command are "down" the transmit power is reduced by 1 dB If all five estimated TPC command are "up" the transmit power is increased by 1 dB Otherwise the transmit power is not changed Transmitter power control range The transmit power of the downlink channels is determined by the network. The power control step size can take four values: 0.5, 1, 1.5 or 2 dB. It is mandatory for UTRAN to support step size of 1 dB, while support of other step sizes is optional. The UE generates TPC commands to control the network transmit power and send them in the TPC field of the uplink DPCCH. Upon receiving the TPC commands UTRAN adjusts its downlink DPCCH/DPDCH power accordingly. Outer loop power control is used to maintain the quality of communication at the level of bearer service quality requirement, while using as low power as possible. The uplink outer loop power control is responsible for setting a target SIR in the Node B for each individual uplink inner loop power control. This target SIR is updated for each UE according to the estimated uplink quality (BLock Error Ration, Bit Error Ratio) for each Radio Resource Control connection. The downlink outer loop power control is the ability of the UE receiver to converge to required link quality (BLER) set by the network (RNC) in downlink. Power control of the downlink common channels are determined by the network. In general the ratio of the transmit power between different downlink channels is not specified in 3GPP specifications and may change with time, even dynamically

Compressed Mode

During inter-frequency handover the UE’s must be given time to make the necessary measurements on the different WCDMA carrier frequency. 1 to 7 slots per frame can be allocated for the UE to perform this intra frequency (hard handover). These slots can either be in the middle of the single frame or spread over two frames.

This compressed mode operation can be achieved in three different methods:

Decreasing the spreading factor by 2:1. This will increase the data rate so bits will get sent twice as fast. Puncturing bits. This will remove various bits from the original data and hence reduce the amount of information that needs to be transmitted. The higher layer scheduling could also be changed to use less timeslots for user traffic. From the 3GPP TS 25.212: In compressed frames, Transmission Gap Length slots from Nfirst to Nlast are not used for transmission of data. As illustrated below, the instantaneous transmit power is increased in the compressed frame in order to keep the quality (BER, FER, etc.) unaffected by the reduced processing gain. The amount of power increase depends on the transmission time reduction method. What frames are compressed, are decided by the network. When in compressed mode, compressed frames can occur periodically, or requested on demand. The rate and type of compressed frames is variable and depends on the environment and the measurement requirements. The frame structure for uplink compressed frames is illustrated below. There are two different types of frame structures defined for downlink compressed frames. Type A maximises the transmission gap length and type B is optimised for power control. The frame structure type A or B is set by higher layers independent from the downlink slot format type A or B. With frame structure of type A, the pilot field of the last slot in the transmission gap is transmitted. Transmission is turned off during the rest of the transmission gap (below). With frame structure of type B, the TPC field of the first slot in the transmission gap and the pilot field of the last slot in the transmission gap is transmitted. Transmission is turned off during the rest of the transmission gap (below).