Supporting Femtocell on Interference Mitigation for Unconnected Mobile
Supporting Femtocell: on Interference Mitigation for Unconnected Mobile Station Document Number: IEEE C 80216 m-09_1967 Date Submitted: 2009 -08 -28 Source: Ying Li, Baowei Ji, Zhouyue Pi, Jung Je Son, Anshuman Nigam Email: yli 2@sta. samsung. com Phone: +1 -972 -761 -7903 Samsung Electronics Venue: IEEE Session #63 Base Contributions: Re: Contribution in support of a comment on LB 30 Purpose: Notice: Discussion and Approval This document does not represent the agreed views of the IEEE 802. 16 Working Group or any of its subgroups. It represents only the views of the participants listed in the “Source(s)” field above. It is offered as a basis for discussion. It is not binding on the contributor(s), who reserve(s) the right to add, amend or withdraw material contained herein. Release: The contributor grants a free, irrevocable license to the IEEE to incorporate material contained in this contribution, and any modifications thereof, in the creation of an IEEE Standards publication; to copyright in the IEEE’s name any IEEE Standards publication even though it may include portions of this contribution; and at the IEEE’s sole discretion to permit others to reproduce in whole or in part the resulting IEEE Standards publication. The contributor also acknowledges and accepts that this contribution may be made public by IEEE 802. 16. Patent Policy: The contributor is familiar with the IEEE-SA Patent Policy and Procedures: <http: //standards. ieee. org/guides/bylaws/sect 6 -7. html#6> and <http: //standards. ieee. org/guides/opman/sect 6. html#6. 3>. Further information is located at <http: //standards. ieee. org/board/pat-material. html> and <http: //standards. ieee. org/board/pat >.
Femto IM in current AWD • Focus on MS connected with serving base station. See the following text in current AWD. – “An MS may be requested by its serving macro ABS or Femto ABS to report the signal strength measurement of neighbor BSs, including macro and/or Femto BSs. The reported information can be used by the serving ABS to coordinate with its neighbor BSs to mitigate the interference at the MSs. – “Large interference from an inaccessible Femto ABS may trigger a nearby MS to report the interference to the serving ABS, and the report information should include system information of the inaccessible Femto ABS (e. g. , BS_ID of the Femto ABS). • How if a non-member MS is not connected, but receives a strong interference from the CSG femto? – A. Non-member MS may still be able to perform ranging to macro or other BS – B. Non-member MS may not be able to range to macro or other BS
Proposed Solution • Large interference from an inaccessible Femto ABS may trigger a nearby MS to report the interference to the serving ABS using a message AAI_IM-REQ, and the report information should include system information of the inaccessible Femto ABS (e. g. , BS_ID of the Femto ABS). • If it is not connected with the ABS yet, the AMS may send AAI_IM-REQ to the ABS before or after the authentication phase so that the ABS may negotiate with an interfering Femto ABS to mitigate the interference.
Proposed Solution (Cont. ) • Large interference from an inaccessible Femtocell may saturate or block the MS radio receiver, such that it will not able to maintain the communication with the serving BS. • If an AMS is seriously interfered by a neighbor CSG-closed Femtocell ABS and cannot get any service from the network, the MS may request the ABS to mitigate the interference by sending an AAI_RNG-REQ message with Ranging Purpose Indication Bit#5 set as ‘ 1’, together with AMS ID and information for authentication. • Having received this ranging request message, the CSG-closed Femto ABS may authenticate the AMS request and mitigate the interference. • Advantage: – Prevent the CSG femto generating coverage hole to non-member MS
- Slides: 4