1. Femto cell BTS 14th May 2007 Koo, Yeon Sang Deputy General Manager Technical Strategy Team LG TeleCom, Ltd. Tel: (82-2) 6006-4334 Fax :(82-2) 6006-4222 yskoo@lgrtel.co.kr LG TeleCom, Inc., grants a free, irrevocable license to 3GPP2 and its Organizational Partners to incorporate text or other copyrightable material contained in the contribution and any modifications thereof in the creation of 3GPP2 publications; to copyright and sell in Organizational Partner's name any Organizational Partner's standards publication even though it may include all or portions of this contribution; and at the Organizational Partner's sole discretion to permit others to reproduce in whole or in part such contribution or the resulting Organizational Partner's standards publication. LG TeleCom, Inc., is also willing to grant licenses under such contributor copyrights to third parties on reasonable, non-discriminatory terms and conditions for purpose of practicing an Organizational Partner’s standard which incorporates this contribution. This document has been prepared by LG TeleCom, Inc., to assist the development of specifications by 3GPP2. It is proposed to the Committee as a basis for discussion and is not to be construed as a binding proposal on LG TeleCom, Inc. LG TeleCom, Inc., specifically reserves the right to amend or modify the material contained herein and to any intellectual property of LG TeleCom, Inc.,other than provided in the copyright statement above.

2. 3GPP2-C00-20070514-xxx 1/2 Concept of FEMTO BTS Femto BTS Internet (ISP’s IP Network) Indoor (Home or Office) Mobile Operator’s Core Network Broadband (xDSL, Cable, Fiber Fast Ethernet)  System description - Femto:10 is a very small unit (nano  pico  femto) - Femto BTS: indoor BTS for small/low-power/residential/office uses. - Connects 2G/3G voice and data to mobile operator’s backbone through broadband internet - Uses existing handsets - Femto BTS, Home AP, Home e Node B. are all used in the same sense -15 2G/3G Radio Access Network

3. 3GPP2-C00-20070514-xxx 2/2 Benefit of FEMTO BTS - Improve the indoor coverage of wireless services - Enhance the performance and QoS of wireless data services delivered in the home Coverage Improvement Infrastructure cost decrease New service Offering - Decrease the operator’s infrastructure costs - Development of new service offerings at home (e.g: Homezone subscription plan) - Key player of FMC (VS. Dual mode UMA/Wifi) FMC Acceleration FMC Acceleration According to OVUM*’s data, the proportion of call originating from residential area reaches 30~40% in the western Europe and upto 60% in the U.S. for some operators. Under these circumstances, FEMTO BTS has the following benefits. * 3G Home gateways: Opportunities and Challenge(2007)

4. 3GPP2-C00-20070514-xxx 3/2 Network Architecture(1/2) Modified BSC Concentrator Mobile networks have not been designed to support millions of base stations. The solutions should be able to route all incoming/outgoing voice calls and data traffic to the devices attached to a Femto BTS. The solutions also allow the seamless mobility management as the devices enter or leave their homezone. Fig.A Femto BTS is connected to the BSC via the Abis interface - Modification of the BSC to manage Femto BTS. - Emulating the standard Abis interface between the base stations and the BSC. - It will probably be used to start Femto BTS operations. - But questions remain regarding its scaleability if millions of Femto BTS. Fig.B Femto BTS is managed with concentrators - Aggregate traffic from tens of thousands Femto BTS and connect to the mobile core network via the A interface - Ip.access has developed a proprietary solution based on this architecture.(3GPP)

5. 3GPP2-C00-20070514-xxx 4/2 Network Architecture(2/2) Fig.C The UMA solution (3GPP) Fig.D SIP/IMS - UMA has been initially developed to connect WiFi access points to a GSM network, and it has been included in the 3GPP standard in this context. - Kineto Wireless promotes the use of the UMA architecture in the context of Femto BTS. - The idea involves putting a UMA client into the Femto BTS, and then managing Femto BTS in the network with the UMA Network Controller (UNC) of the UMA architecture. - IMS architecture to integrate Femto BTS into the core network. - This assumes SIP enabled Femto BTS that can dialog with a SIP server in the network. - 3Way Networks and Ubiquisys support this architecture in their Femto BTS products. (similar to the UMA one: Femto BTS are seen as end-us er devices by the network and uses an integrated SIM c ard for authentication.)

6. 3GPP2-C00-20070514-xxx 5/2 Challenge of Developing FEMTO BTS Same 3GPP2 interfaces and functionality Use of Standard terminals(No impact on the end-user handset) Integration with the macro network Mobility to and from Macro layer and Femto including soft HO Same frequency as macro layer Self-configurability by the end user Radio management Control of quality of service Key requirements for Femto BTS are as follows

7. 3GPP2-C00-20070514-xxx 6/2 Conclusion Many mobile operators are interested in Femto BTS. Femto Cell BTS provides Savings on backhaul costs Improve in-building coverage Reduce churn A platform on which operators can build an effective delivery system for triple- and quadruple-play services. But, the current lack of unified standards is likely to cause delays and inefficiency as multiple pseudo-standard solutions emerge So, Femto Cell Solution should be standardized in 3GPP2.

8. 3GPP2-C00-20070514-xxx 7/2 Ref. Femto BTS Products  The progress of major developers of Femto BTS is shown in the table on the right.  3GPP developers lead the trend.  However, Airvana, Airwalk, and others have announced the development of Femto for 3GPP2 or are in the process of doing so.  The chipset from PicoChip is SDR type modem, which allows easy development into various forms, and the number of 3GPP2 specific vendors is likely to increase (GWT). *Femto BTS Equipment Vendors (Source: Unstrung insider, 2007)