=>Mobile Phone Glossary(5)

PDC
Personal Digital Cellular: the 2G TDMA-based protocols used in Japan, owned by NTT DoCoMo. PDC services operate in the 800 and 1500 MHz bands. PersonalJava A Java platform optimized for the requirements and constraints of mobile devices. Platform A set of technology, which acts as a foundation for real-world applications, or higher-level platforms.

Symbian
OS includes C++ APIs, a leading Java implementation, an application suite and integration with wireless and other communications protocols. Polyphonic Ringtones Todays poly ringtones are almost as good as the original records, the quality gets better all the time due to continuous improvement in mobile phone audio technology. Most modern mobile phones with play 16 track tunes. Whilst the early mobile phones that would only play monophonic sounds are still around it is only a matter of time before all mobile phone manufacturers produce handsets that play polyphonic tones. Polytones sound good and most hits are available to be transmitted in stereo to give up to 40 different notes playing at a time. Quartz Code-name for a tablet-like, quarter-VGA portrait screen size, pen-based, reference design. Reference design User interface designs for Symbian OS delivered to Symbian licensees Service provider A company that provides mobile phone users with services and subscriptions to mobile phone networks.

SIM
Subscriber Identity Module. The SIM card is the smart card inserted inside all GSM phones. It identifies the user account to the network, handles authentication and provides data storage for basic user data and network information. It may also contain some applications that run on a compatible phone (SIM Application Toolkit). Smartphone A generic name for voice centric mobile phones with information capability. The Ericsson R380 Smartphone is an example of such a Symbian OS phone. SMS Short Message Service: available on digital GSM networks allowing text messages of up to 160 characters to be sent and received via the network operator's message center to your mobile phone, or from the Internet, using a so-called "SMS gateway" website. If the phone is powered off or out of range, messages are stored in the network and are delivered at the next opportunity. Symbian Connect The PC-based Symbian Connect is a system for data synchronization, file management, printing via PC, application installation from a PC, and other utility functions allowing Symbian OS phones to integrate effectively with PC and server-based data. Symbian Developer Network The developers' support network for Symbian OS, where you will find all the resources to enable you to develop world-class applications for Symbian OS phones. Symbian OS Symbian's advanced open standard operating system for data enabled mobile phones. It includes a multi-tasking multithreaded core, a user interface framework, data services enablers, application engines and integrated PIM functionality and wireless communications.

SyncML
Synchronization Markup Language, an industry-wide effort to create a single, common data synchronization protocol optimized for wireless networks. SyncML's goal is to have networked data that support synchronization with any mobile device, and mobile devices that support synchronization with any networked data. The SyncML structured data layer will use XML wherever appropriate. SyncML is intended to work on transport protocols as diverse as HTTP, WSP (part of WAP) and OBEX, and with data formats ranging from personal data (e.g. vCard & vCalendar) to relational data and XML documents. The SyncML consortium was set up by IBM, Nokia and Psion among others. Symbian is a sponsor of the SyncML consortium.

TACS
Total Access Communication System: a British 1G analog mobile telephone standard based on the US AMPS system. It was later adopted in other countries including Hong-Kong and Japan. TDMA 1. Time Division Multiple Access: a digital wireless telephony transmission technique. TDMA allocates each user a different time slot on a given frequency. GSM, D-AMPS, PDC and DECT use TDMA in one form or another. 2. A name generally used for D-AMPS. TDMA networks are operated in the US, Latin America, New Zealand, parts of Russia and Asia Pacific.

UMTS
Universal Mobile Telecommunications Service, part of the IMT-2000 initiative, is a 3G standard supporting a theoretical data throughput of up to 2 Mbps. First trials started in 2001. It should be rolled out in most of the world by 2005.

Unicode
A 16-bit character encoding scheme allowing characters from Western European, Eastern European, Cyrillic, Greek, Arabic, Hebrew, Chinese, Japanese, Korean, Thai, Urdu, Hindi and all other major world languages, living and dead, to be encoded in a single character set. The Unicode specification also includes standard compression schemes and a wide range of typesetting information required for worldwide locale support. Symbian OS fully implements Unicode. vCalendar Defines a transport- and platform-independent format for exchanging calendar and schedule information so that any vCalendar-compliant application can send or receive calendaring and scheduling information to or from any other vCalendar-compliant application. For instance, users with mobile phones running vCalendar-aware applications can schedule meetings automatically over an infrared link or via sending an SMS. vCard Standard defining the format of an electronic business card. All devices supporting vCard can exchange information such as phone numbers and addresses. For instance a user with a vCard-aware phonebook application on a handheld computer can easily transfer names and phone numbers to a vCard-aware mobile phone.VGA Video Graphics Array: “standard” screen size of 640 by 480 pixels.

WCDMA
Wide-band CDMA: a CDMA protocol originated by NTT DoCoMo and now adopted for third-generation use by ETSI in Europe. WCDMA supports very high-speed multimedia services such as full-motion video, Internet access and video conferencing. WAP 1. Wireless Application Protocol: a set of communication protocol standards to make accessing online services from a mobile phone simple. 2. WAP was conceived by four companies: Ericsson, Motorola, Nokia, and Unwired Planet (today called Phone.com). The WAP Forum is an industry association with over 200 members. Symbian is a full member of the WAP Forum.

=>Mobile Phone Glossary(4)

J2ME

Java 2 Platform, Micro Edition (J2ME): The edition of the Java platform that is targeted at small, standalone or connectable consumer and embedded devices. The J2ME technology consists of a virtual machine and a set of APIs suitable for tailored runtime environments for these devices. The J2ME technology has two primary kinds of components – configurations and profiles. JavaPhone A Java API specification controlling contacts, power management, call control, and phonebook management, intended specifically for the programmability requirements of mobile phones.

JTAPI The Java Telephony API is an extensible API that offers an interface to all call control services (from those needed in a consumer device up to those of call centers). JTAPI is part of the JavaPhone API. Kernel Core of an operating system, a kernel manages the machine's hardware resources (including the processor and the memory), and provides and controls the way any other software component can access these resources. The kernel runs with a higher privilege than other programs (so-called user-mode programs). The power and robustness of an OS's kernel play a major role in shaping overall system design and reliability.

MExE

Mobile Station Application Execution Environment (GSM 02.57): a framework to ensure a predictable environment for third-party applications in GSM or UMTS handsets (ie the Mobile Station). MExE does this by defining different technology requirements called "classmarks". MExE classmark 1 is based on WAP, classmark 2 on PersonalJava and JavaPhone, and classmark 3 on J2ME CLDC and MIDP. Other classmarks may be defined in the future. MExE specifies additional requirements for all classmarks, for instance a security environment, capability and content negotiation, a user profile, user interface personalization, management of services and virtual home environment. A handset can support any number of classmarks.

MIDP

Mobile Information Device Profile. Set of Java APIs that is generally implemented on the Connected Limited Device Configuration (CLDC). It provides a basic J2ME application runtime environment targeted at mobile information devices, such as mobile phones and two-way pagers. The MIDP specification addresses issues such as user interface, persistent storage, networking, and application model. Network operator Company with a license to provide wireless telephony services.

NMT

Nordic Mobile Telephone. One of the earliest 1G cellular network developed jointly in Denmark, Finland, Iceland, Norway and Sweden. Originally operated in the 450 MHz band. Later the 900 MHz was used as well. OBEX Object Exchange: a set of high-level protocols allowing objects such as vCard contact information and vCalendar schedule entries to be exchanged using either IrDA (IrOBEX) or Bluetooth. Symbian OS implements IrOBEX for exchange of vCards, for example between a Nokia 9210 Communicator and an Ericsson R380 Smartphone, and vCalendar.

OS

Operating System: historically, the minimal set of software needed to manage a device's hardware capability and share it between application programs. Practically, "OS" is now used to mean all software including kernel, device drivers, comms, graphics, data management, GUI framework, system shell application, and utility applications. This would define Windows, Palm OS and MacOS as operating systems. Symbian provides an operating system – Symbian OS – tailored for data-enabled mobile phones.

OPL A BASIC-like programming language, for rapid application development, used on Symbian OS. Packet-switching Technique whereby the information (voice or data) to be sent is broken up into packets, of at most a few KB each, which are then routed by the network between different destinations based on addressing data within each packet. Use of network resources is optimized, as the resources are needed only during the handling of each packet. This is an ideal model for ad hoc data communication, and works well also for voice, video and other streamed data. Mobile phones with packet-switched communication appear to be "always connected" to the data network, whereas in the case of circuit-switched connections, setup time takes around 30 seconds to connect from a mobile phone to an ISP. Use of packet-switched network can be charged according to the volume of data transferred and not to any notion of time spent online. PCN Personal Communications Network: another name for GSM 1800 (it is also known as DCS 1800). It is used in Europe and Asia Pacific.

PCS

Personal Communications Service: an American generic term for a mass-market mobile phone service, emphasizing personal communication, independent of the technology used to provide it. PCS includes such digital cellular technologies as GSM 1900, CDMA and TDMA IS-136.

=>Mobile Phone Glossary(3)

GPRS
General Packet Radio Service: a radio technology for GSM networks that adds packet-switching protocols, shorter set-up time for ISP connections, and offer the possibility to charge by amount of data sent rather than connect time. GPRS promises to support flexible data transmission rates typically up to 20 or 30 Kbps (with a theoretical maximum of 171.2 Kbps), as well as continuous connection to the network. A 2.5G enhancement to GSM, GPRS is the most significant step towards 3G, needing similar business model, and service and network architectures. GPRS started to appear in some networks during 2000.
GSM
Global System for Mobile communications, the most widely used digital mobile phone system and the de facto wireless telephone standard in Europe. Originally defined as a pan-European open standard for a digital cellular telephone network to support voice, data, text messaging and cross-border roaming. GSM is now one of the world's main 2G digital wireless standards. GSM is present in more than 160 countries and according to the GSM Association, accounts for approximately 70 percent of the total digital cellular wireless market. GSM is a time division multiplex (TDM) system. Implemented on 800, 900, 1800 and 1900 MHz frequency bands.

GSM Gateway
A mobile phone device thats takes a single SIM card or multiple SIMS and provides a telecoms interface - either Analogue (FXO/FXS) to allow connection to Analogue trunk of a Telephone System (or to allow a standard telephone to connect directly), ISDN Interfaces such as ISDN2e and ISDN30 for connection to ISDN telephone systems and VOIP interfaces to allow the gateway to connect to a Voice Over IP network. The GSM Gateway enables these traditional telephony devices to connect directly to the mobile phone network, usually providing the user with access to cheaper call rates. (see http://www.gsmsave.co.uk/)

HSCSD
High Speed Circuit Switched Data: dedicated circuit-switched data communications technology for GSM which boosts data throughput up to 14.4 Kbps in a single channel, and by aggregating channels, up to 57.6 Kbps. An asymmetrical service can be offered where, for instance, one channel is allocated for the uplink and several are aggregated for the downlink. HSCSD can provide a fixed bit rate (transparent mode) or a variable one (non-transparent mode). In most cases HSCSD is available to network operators as a pure software upgrade. HSCSD started to appear in some networks in 1999.

IMT-2000
International Mobile Telecommunications-2000: term used by the International Telecommunications Union (ITU) for the specification for projected third-generation wireless services. Formerly referred to as FPLMTS, Future Public Land-Mobile Telephone Systems. i-mode Proprietary packet-based information service for mobile phones. i-mode delivers information (such as mobile banking, and train timetable) to mobile phones and enables exchange of email from handsets on the PDC-P network. Launched in 1999 by NTT DoCoMo, i-mode is very popular in Japan (especially for email and transfer of icons), but is not currently being used elsewhere, IrDA 1. A suite of protocols for infrared (IR) exchange of data between two devices, up to 1 or 2 meters apart (20 to 30 cm for low-power devices). IrDA devices typically have throughput of up to either 115.2 Kbps or 4 Mbps. IrDA protocols are implemented in Symbian OS phones, many PDAs, printers and laptop computers. 2. The Infrared Data Association, the industry body that specifies IrDA protocols, originally founded by Hewlett-Packard and others. Java Industry standard object-oriented language and virtual machine, invented by Sun Microsystems and formally released in 1996. Java is an ideal language for network applications and applets. Sun's Java specifications include many Java APIs and platforms, including the JavaPhone API and PersonalJava platform, which are included in Symbian OS.

=>Mobile Phone Glossary(2)

CLDC J2ME Connected Limited Device Configuration. The CLDC serves the market consisting of personal, mobile, connected information devices. This configuration includes some new classes designed specifically to fit the needs of small-footprint devices. Communicator A generic name for information centric mobile phones. In effect a fully featured personal digital assistant and mobile phone in one unit. The Nokia 9210 Communicator is an example of such a Symbian OS phone. Content Provider A company that provides services to mobile phone users or network operators. These services could be shopping, web surfing, chat rooms, playing games, accessing data such as music and books through a server. Crystal Code-name for a half VGA reference design for Symbian OS.

D-AMPS

Digital AMPS (Digital-Advanced Mobile Phone Service) is the digital wireless standard widely used throughout the Americas, Asia Pacific and other areas. D-AMPS uses digital TDMA on the one hand, and is required to be compatible with installed AMPS base station networks on the other. D-AMPS operates on the 800 and 1900 MHz bands.

DCS 1800

Digital Communications System: another name for GSM working on a radio frequency of 1800 MHz. Also known as GSM1800 or PCN, this digital network operates in Europe and Asia Pacific. Digital A way of encoding information. On digital networks, data doesn't need to go though the extra step of being converted to an analog signal, voice is sampled and coded in a way similar to how it is recorded on a CD. Digital networks are fast replacing analog ones as they offer improved sound quality, secure transmission and can handle data directly as well as voice. Digital networks include mobile systems GSM, D-AMPS, CDMA, TDMA and UMTS. Dual band Dual band mobile phones can work on networks that operate on different frequency bands. This is useful if you move between areas covered by different networks. Some networks operate on two bands, for instance GSM-1800 in town centers and GSM-900 in the rest of the country.
Dual mode Dual mode mobile phones have more than one air interface and hence can work on more than one network. One example is phones that operate on both digital and analog networks. They are quite useful if you want the advantages of a digital phone, but regularly visit areas where analog is the only service available.

EDGE

Enhanced Data Rates for GSM Evolution. An enhanced modulation technique designed to increase network capacity and data rates in GSM networks. EDGE should provide data rates up to 384 Kbps. EDGE will let operators without a 3G license to compete with 3G networks offering similar data services. EDGE is not expected before 2001 at the earliest.
EPOC Deprecated term. Refer to Symbian OS.

E-TACS

Extended Total Access Communications System: a 1G mobile phone network developed in the UK and available in Europe and Asia.
FCT Fixed Cellular Terminal - also known as : GSM Gateway, GSM Modem, GSM Router, Mobile Gateway, channel bank, GSM channel Bank, ISDN GSM Gateway, analogue GSM gateway.

Fixed Cellular Terminal Mobile

Device that allows fixed telephony devices such as PBX Telephone Systems to connect directly to the GSM Mobile Phone Network - This may be to allow PBX users to call colleages on their mobiles free of charge, or call other mobile users at reduced rates (depending upon available tariffs) - or for use in remote offices where no fixed line services are available (eg building site / remote monitoring post) - for landline substitution then Fixed Cellular Terminals are available that can provide voice, fax and data over the GSM network such as the Ericsson F251m .

=>Mobile Phone Glossary(1)

Mobile Phone Glossary
1G
In mobile telephony, first-generation systems were analog, circuit-switched. Voice links were poor, handoff unreliable, capacity low, and security non-existent. 1G systems are not now under active development – indeed, in some areas 1G spectrum is being auctioned for 2G and 3G use.

2G
In mobile telephony, second-generation protocols use digital encoding and include GSM, D-AMPS (TDMA) and CDMA. 2G networks are in current use around the world. These protocols support high bit rate voice and limited data communications. They offer auxiliary services such as data, fax and SMS. Most 2G protocols offer different levels of encryption..

2.5G
In mobile telephony, 2.5G protocols extend 2G systems to provide additional features such as packet-switched connection (GPRS) and enhanced data rates (HSCSD, EDGE).

3G
In mobile telephony, third-generation protocols support much higher data rates, measured in Mbps, intended for applications other than voice. 3G networks trials started in Japan in 2001. 3G networks are expected to be starting in Europe and part of Asia/Pacific by 2002, and in the US later. 3G will support bandwidth-hungry applications such as full-motion video, video-conferencing and full Internet access. http://www.3gpp.org/

AMPS
Advanced Mobile Phone System: a 1G standard which operates in the 800-900MHz-frequency band. It is still widely used in the United States.
Analog The simple way to transmit speech, which is translated into electronic signals of different frequency and/or amplitude. The first networks for mobile phones, as well as broadcast transmissions, were analog. Due to being longer established in some countries, analog networks may offer better coverage than digital networks, however analog phones are less secure and suffer more from interference where the signal is weak. Analog systems include AMPS, NMT and ETACS.

API
Historically, "application programming interface". Practically, an API is any interface that enables one program to use facilities provided by another, whether by calling that program, or by being called by it. At a higher level still, an API is a set of functionality delivered by a programming system, and as such the mix of APIs in a particular system tells you what that system can do.
Bluetooth An open specification for seamless wireless short-range communications of data and voice between both mobile and stationary devices. For instance, it specifies how mobile phones, computers and PDAs interconnect with each other, with computers, and with office or home phones. The first generation of Bluetooth permits exchange of data up to a rate of 1 Mbps per second, even in areas with much electromagnetic disturbance. It transmits and receives via a short-range radio link using a globally available frequency band (2.4 GHz ISM band).
bps Bits per second: a way of quantifying data transmission throughput. It is the number of pieces of information (bits) transmitted or received per second.
C++ An industry standard object-oriented compiled language, formally standardized in 1998, but tracing its history to the early 1980s, with an heritage in C and Simula. C++ is a general-purpose programming language with a bias towards systems programming. C++ runs on most computers from the most powerful supercomputers to the ubiquitous personal computers. Symbian OS is written in C++.

CDMA
Code Division Multiple Access: a digital wireless telephony transmission technique. 1. CDMA allows multiple frequencies to be used simultaneously (Spread Spectrum). The CDMA idea was originally developed for military use over 30 years ago. 2. The CDMA standards used for second-generation mobile telephony are the IS-95 standards championed by QUALCOMM.
Cellular Radio The technology that has made large scale mobile telephony possible. Current cellular networks reuse the same radio frequencies by assigning them to cells far enough apart to reduce interference. A cell is the geographical area covered by one radio base station transmitting/receiving in the center. The size of each cell is determined by the terrain, transmission power, and forecasted number of users. Service coverage of a given area is based on an interlocking network of cells, called a cell system.
Circuit-Switching Means of creating a connection by setting up a dedicated end-to-end circuit, which remains open for the duration of the communication.

References

References
1 US patent 2,292,387, “Secret Communications System”
2 Robert A. Scholtz, “The Origins of Spread-Spectrum Communications,” IEEE Trans.
Comm., Vol. Com-30, No. 5, May 1982, pp. 822-854
3 G.R. Cooper and R.W. Nettleton, "A Spread Spectrum Technique for High-Capacity
Mobile Communications," IEEE Transactions on Vehicular Technology, VT-27, pp.
264-275, 1978
4 G. Turin, “The Effects of Multipath and Fading on the Performance of Direct-
Sequence CDMA Systems,” IEEE Journal on Selected Areas in Communications,
Vol. SAC-2, No. 4, July 1984, pp. 597-603
5 R. Price and P. E. Green, Jr., “A Communication Technique for Multipath Channels,”
Proc. IRE, vol. 46, pp. 555-570, March 1958.
6 G. Turin, “Introduction to Spread-Spectrum Antimultipath Techniques and Their
Application to Urban Digital Radio,” Proc IEEE, Vol. 68, No. 3, March 1980
7 Proc. 2nd Nordic Seminar on digital Land Mobile Radio Communications, 14-16
October, 1986
8 K.S. Gilhousen, et al, “On the Capacity of a Cellular CDMA system,” IEEE Trans,
Veh. Tech. Vol. 40, Issue 2, May 1991, pp 303-312
9 A. Baier, U.C. Fiebig, W. Granzow, W. Koch, P. Teder, “Design Study for a CDMAbased
Third Generation Mobile Radio System,” IEEE Journal on Selected Areas in
Communications, pp. 733-743, May 1994
10 P.G. Andermo, L-M. Ewerbring, “Looking far beyond the concepts proposed for
current cellular systems – A CDMA-Based Radio Access Design for UMTS,” IEEE
Personal Communications, pp.48-53, Feb 1995
11 M. Ewerbring, W. Granzow, P. Teder, “Evaluation of a wideband CDMA testbed for
future wireless systems,” IEEE 4th International Symposium on Spread Spectrum
Techniques and Applications, 22-25 Sept 1996, Vol. 1, pp. 254-258
12 M. Ewerbring, J. Färjh, W. Granzow, “Performance Evaluation of a Wideband
Testbed based on CDMA,” Proc. 47th IEEE Vehicular Technology Conference, 4-7
May, 1997, Vol. 2, pp.1009-1013
13 Ericsson US patents 5,991,330, 5,930,366, 6,185,244, 6,526,091 and others
14 Ericsson EP patent 535714 and others
15 Ericsson US patent 5,828,659

16 Ericsson US patents 5,533,014, 5,883,899 and others
17 Ericsson US patent 6,163,533 and others
18 Motorola US patent 5,204,876
19 Ericsson US patent 6,781,970 and others
20 Ericsson US patent 5,230,003 and others
21 Ericsson US Patents 6,029,125, 6,301,556, 6,058,359, 6,564,183, 6,192,335,
6,424,938, 6,275,798 and others

References : http://www.ericsson.com/

Conclusion

In this paper we have clarified some misconceptions surrounding the development of WCDMA, the radio access part of the UMTS 3G standard. We gave some technical and historical insight into spread spectrum techniques and the multiple access technology known as CDMA. These were all invented and developed in the 1950s during the early Cold War. While for a long time used mainly for military purposes, CDMA technology started being considered for digital cellular systems in the late 1970s and was part of candidate proposals for the GSM system in 1986. CDMA was later used in the 2G standard IS-95 and the 3G standard WCDMA. We provided an overview of the development of the WCDMA standard, starting with pioneering contributions in CDMA-based 3G in the early 1990s. WCDMA resulted from parallel European and Japanese 3G developments which were finally merged in 1997 to create the global WCDMA standard we know today, released in its first version in 1999. We then specifically described a number of important technical challenges and features of WCDMA. We showed that while the WCDMA and IS-95 standards both use the old CDMA technology, specific technical solutions adopted within the two standards are different. The main reason for this is differences in the overall requirements placed on the standards – 3G versus 2G requirements. Also, since commercial deployment of WCDMA was expected several years later than that of IS- 95, more advanced solutions could be used in WCDMA due to the advances in signal processing technology. Besides the differences between the two standards, some of the WCDMA solutions, such as several aspects of the uplink structure, were also later adopted in Cdma2000, a modification of the IS-95 standard, to meet 3G requirements. We also discussed the FRAND commitment for patents essential to telecom standards. The guiding principles for license royalty levels are accumulated reasonableness and proportionality to essential patent ownership. Patent transparency is therefore very important for the marketplace and patent essentiality assessments are welcomed tools for achieving this. With this paper we have shown that WCDMA is not based on IS-95, but is the result of developments started in Europe and Japan in the early 1990s. The requirements on the WCDMA standard were very different from those on IS-95, leading to new and different technical solutions. By highlighting some of these solutions, the paper provides some increased transparency regarding the origin of the innovations of the WCDMA standard and hence also to the situation surrounding patents essential to it.

References : http://www.ericsson.com/

Telecommunications standards and patents

The success of mobile cellular standards can be largely attributed to the open and collaborative standardization process that standards are created in. Within Standards Development Organizations (SDOs), market participants jointly develop open standards by sharing know-how with each other, resulting in widely inter-operable products and therefore a competitive market. There is, however, a conflict between the voluntary invention-sharing of the SDOs and the concept of patents, which give rights-holders exclusive rights to inventions. To avoid patent-owners blocking telecoms standards, SDO participants agree to waive their normal patent rights. The rights waiver, known as the FRAND promise, means the patent-holder agrees to license its standards-essential patents on a fair, reasonable and non-discriminatory basis. The meaning of FRAND can be broken down into the following meaning, which is observed by the vast majority of the holders of essential cellular patents in the world:
1. Aggregated reasonable terms (ART). Essential patent-holders agree to grant licenses on terms that are objectively commercially reasonable, taking into account the overall licensing situation including the cost of obtaining all necessary licenses from other relevant patent-holders for all relevant technologies in the end product.
2. Proportionality. Compensation under FRAND must reflect the patent-holder’s proportion of all essential patents, but the equation is not just numeric. The compensation must within reasonable bounds reflect the contribution. Mobile cellular standards consist of a multitude of different technologies, new and old. Some of the technologies, such as CDMA or TDMA, are so old that any patents covering them have expired long ago. However, most innovation occurs during the SDO process, within a certain framework of requirements, set within the SDO itself or by higher-level SDOs. Requirements differ across standards and consequently inventions tend to be different too, as we have seen many examples of in this paper. Essential patents are complementary, rather than competitive, meaning an equipment vendor needs licenses to all essential patents owned by all patentholders, not just some of them. The proportionality part of FRAND necessitates a high degree of transparency in the marketplace. In bi-lateral negotiations, allegedly essential patents are scrutinized carefully in terms of essentiality and validity. Thirdparty efforts to examine patent claims are also highly useful, especially for those who do not have the expertise to make such assessments themselves. This paper aims to help increase the transparency of the essential patent landscape surrounding WCDMA by providing information about how the standard and the underlying technologies developed.

References : http://www.ericsson.com/

Broadcast and multicast services

Broadcast and multicast services
Multimedia Broadcast and Multicast Service (MBMS) provides support for multicast and broadcast services such as mobile TV. With MBMS, the same content is transmitted to multiple users in a unidirectional fashion, typically by multiple cells, to cover a large area where the service is provided. To a user at the cell edge, the signal from the neighboring base station can be used to improve the received signal quality. In essence, this is a form of downlink soft handover and leads to a significant improvement of data rates and coverage for broadcast services.

As with HSPA, strong emphasis was put on supporting MBMS on the same carrier as other (speech and data) traffic to provide the operator with maximum flexibility. In Cdma2000/EV-DO, a separate carrier is required, which also necessitates aseparate receiver in the mobile device.

References : http://www.ericsson.com/

High-speed packet data

Around the turn of the millennium, 3GPP started development of High-Speed Packet Access (HSPA), with the first version of the specifications released in early 2002 and additional features released in the following years. HSPA is the popular name of WCDMA with enhanced downlink and uplink transmission schemes further optimized for packet data, plus features to further enhance the user experience, such as providing an “always on” perception.HSPA is based on shared-channel transmission with channel-dependent scheduling;fast link adaptation, hybrid ARQ with soft combining and a short Transmission Time Interval (TTI). These features are illustrated in Figure 11. Later releases of the HSPA specifications will provide support of multiple-input, multiple-output (MIMO) transmission schemes, higher-order modulation and multi-carrier use to further boost peak data rates up and above 100Mbps. Worth noting is that many of these basic principles were already part of the evolution of GSM to GPRS and EDGE in the mid to late 1990s.

Similar principles were also used when Cdma2000 was complemented by Evolution Data Only (EV-DO), also called IS-856. In WCDMA/HSPA, strong emphasis was put on the possibility of supporting voice and high-speed packet data on the same carrier to ensure a smooth introduction of high-speed services into existing WCDMA networks. In contrast, EV-DO uses a different frame structure than Cdma2000 and as a result separate carriers need to be used for support of voice services and highspeed packet data. The flexibility for Cdma2000 operators is restricted when introducing high-speed packet data. Since the carrier bandwidth is several times
smaller in Cdma2000/EV-DO than in WCDMA/HSPA, the peak rates achievable in EV-DO are several times lower than in HSPA.
References : http://www.ericsson.com/

Coherent uplink detection

Coherent uplink detection
Coherent detection allows data reception in bad channel conditions and can increasethe capacity or the data rate of the system. This technology is, for instance, used inGSM and requires so-called “pilot symbols” (“synch words” in GSM) to be transmittedalong with the data. The WCDMA system included such pilot symbols in both thedownlink and the uplink directions, already from its earliest versions and theCdma2000 standard later also adopted uplink pilots. This gave Cdma2000 aperformance improvement over IS-95, which did not allow coherent uplink detection.Not only the uplink pilot symbols but much of the modulation structure of the
Cdma2000 uplink was made similar to that of WCDMA, which in turn was largely nherited from the early WCDMA concept work in the FRAMES project.

OVSF codes

The purpose of 3G was to accommodate an anticipated need for mobile high-speed data communication, even though it was not easily predicted what that data would beor even in which direction it might predominantly flow – from the mobile device or tothe mobile device. Therefore, a major challenge in WCDMA was to create a highlyflexible bearer system that could carry all sorts of possible “multimedia” flows.One feature that provides flexibility of the so-called physical layer of the WCDMA airinterface is the use of Orthogonal Variable Spreading Factor (OVSF) codes [18].Such codes facilitate bit-rate variability while minimizing interference and are formedthrough a code-tree principle. Certain branches in the code-tree are prohibited foruse to minimize cross-talk between users. These codes, together with a flexible rate adaptation algorithm, allowed for a highly versatile variable rate configuration of thephysical layer that could easily meet the flexibility needs of 3G.


Data rate indication

Accommodating variable rate data flows on the physical layer also entails theproblem of how to notify the receiver about the data rate currently being used.Without this knowledge, the receiver cannot process the received signal in the first place. The main solution selected in WCDMA was to add specific information with afixed and known coding, the Transport Format Combination Indicator (TFCI), to the transmitted signal, notifying the receiver about the instantaneous data rate. More precisely, it informs the receiver about all the transport formats used in the currently used transport channels [19]. The alternative solution to TFCI would be to let the receiver blindly guess what transport formats are used, by some sort of trial-anderror procedure, often denoted “blind rate detection” [20].The WCDMA standard typically uses TFCI, but also allows for the optional omission of TFCI. In the downlink, for a pure low-rate speech call, blind transport format detection (blind rate detection of multiple parallel data streams) is used.The IS-95/Cdma2000 standard does not use TFCI and requires blind rate detection.

Speech codec

To transmit speech signals efficiently while maintaining high system capacity in a cellular system, some kind of speech compression or decompression algorithm, or speech codec, is always used. The Adaptive Multi-Rate (AMR) speech codec was originally developed and selected for use in GSM because of its high voice quality at a low bit rate [21]. AMR has also proven to meet higher demands and expected future needs and therefore the 12.2Kbps AMR codec was selected as the primary speech codec for WCDMA.

The speech codec used in IS-95/Cdma2000 was first the 13Kbps Qualcomm Code Excited Linear Prediction (QCELP) and later the 8.5Kbps Enhanced Variable Rate Codec (EVRC) and modifications thereof.

References : http://www.ericsson.com/

Random access

Random access, realized in WCDMA through the Random Access Channel (RACH), is the mechanism through which the mobile terminal performs the initial access to the system. As the terminal is not yet connected to the system, no uplink codes have been allocated, nor is there any control of the uplink power. Thus, mechanisms for RACH code allocation and power setting were needed. To minimize signaling and required power, a solution was adopted in WCDMA in which no explicit signaling of codes is needed. All RACH-related codes are derived according to given rules using only the downlink, that is the transmission from the network, scrambling code and a signature that is randomly selected by the mobile device.

As illustrated in Figure 10, in WCDMA preambles with randomized signatures are sent (uplink) with increasing power in a “ramping” procedure. When the power is sufficient, the network transmits an acquisition indicator to request transmission of the actual message from the terminal. This ramping procedure is very fast and together with the signature randomization leads to an efficient, high-capacity RACH in WCDMA [17]. In contrast, the IS-95/Cdma2000 standard uses random access parameters derived from the serial number of the mobile device and is based on time randomization instead of signature randomization. In IS-95/Cdma2000 the entire random access message is transmitted and retransmitted until received by the network,which is less efficient.

References : http://www.ericsson.com/

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Uplink power control

The “near-far problem” resulting from using DS-CDMA for cellular was already known in the late 1970s and one envisaged solution was to use some form of power control in the uplink, that is the transmission from the mobile device to the network [3, 4]. Figure 9 shows two principles for uplink power control. Open-loop essentially means that the mobile device sets itstransmission power based on measurements of the received signal power, while closed-loop means the mobile device sets its transmission power based on explicit commands received from the network. Such commands are in turn based on measurements of the received signal made at the network side.

When IS-95 was defined, a combination of open-loop and closed-loop uplink power control was chosen and standardized as a solution to the “near-far problem”. This meant that the mobile device set its power based on both the received signal power as well as on commands received from the network. This scheme was later inherited by Cdma2000, a modification of the IS-95 standard. However, when the uplink power control solution was standardized for WCDMA, no
particular benefits of such a dual-loop solution could be identified and instead a pure closed-loop system was selected, but with an update rate twice as high (1500Hz versus 800Hz).

References : http://www.ericsson.com/
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History of WCDMA

While GSM took its first steps towards global success, programs to develop 3G systems began in Europe. 3G referred to a system not only optimized for speech, but also with a high service flexibility and high throughput and capacity for high-speed data. It was anticipated that such a system would be needed at the turn of the millennium. Several potential multiple access concepts for 3G, including Advanced TDMA (ATDMA, based on TDMA) and Code Division Testbed (CoDiT, based on DSCDMA), were studied in the RACE II project as part of the third EU frame program for pan-European research collaboration which began in 1992. Ericsson was heavily involved in CoDiT, which aimed to define a wideband (around 5MHz per carrier) DSCDMA- based radio access for 3G and to create a testbed to demonstrate its characteristics [9, 10]. The CoDiT testbed work, which included field demonstrations, concluded successfully in 1994 and led to the creation of the first feasible wideband CDMA concept for cellular.

References : http://www.ericsson.com/

3G-WCDMA

Wideband Code Division Multiple Access (WCDMA)

• WCDMA is a wideband spread-spectrum 3G mobile telecommunication air interface that utilizes code division multiple access (or CDMA the general multiplexing scheme, not to be confused with CDMA the standard). It provides simultaneous support for a wide range of services with different characteristics on a common 5MHz carrier.The term WCDMA also refers to one of the International Telecommunications Union's IMT-2000 standards, a type of 3G cellular network. WCDMA is the technology behind the 3G UMTS standard and is closely allied with the 2G GSM standard. It provides new service capabilities, increased network capacity and reduced cost for voice and data services.The term 'WCDMA Evolved' describes the evolution of WCDMA, addressing both operators' needs for efficiency and users' demands for enhanced experience and convenience. The first steps of this evolution are HSDPA and Enhanced Uplink.


• Introduction
  This paper describes the evolution of Wideband Code Division Multiple Access (WCDMA)1, which is the radio access network part of the Universal Mobile Telephony System (UMTS), the most widely deployed 3G cellular standard in the world.
  
  Section 2 briefly reviews the history of spread spectrum technology, covering the key developments of spread spectrum and CDMA in the 1950s and the early proposals of CDMA-based cellular systems in the 1980s. Note that throughout this paper, the acronym CDMA is used consistently to refer to the basic multiple access principle and not to the IS-95 family of standards, which is sometimes also referred to as “CDMA”.
  
  Section 3 focuses on the development of the successful WCDMA 3G cellular standard fromthe early 1990s up to the release of the first version of the UMTS standard in 1999.
  
  In section 4 some of the key technologies and innovations of WCDMA are exemplified. Technical challenges and requirements behind the solutions are described, noting that they were largely different from those of the older 2G standard IS-95. As a consequence, WCDMA and the IS-95 family of standards include different technical solutions.
  
  Section 5 discusses the role of the open, collaborative standardization process of mobile cellular standards, the relation to so-called “FRAND” commitments for essential patents and the importance of transparency in technology contribution.
  
  An appendix is also included, clarifying some of the basic differences between the WCDMA standard and the IS-95 family of standards, particularly those related to the air interface.
  
  
  References : http://www.ericsson.com