Title: Coordinated coexistence between wireless networks deployed in adjacent frequency allocations Document Number: S802.16m-08/604 Date Submitted: July 16, 2008 Source: Mariana Goldhamer Voice: ALVARION 21a HaBarzel Street, Tel Aviv, Israel Venue: Session #56, July, 2008 Base Document: C802.16m-08/604 Purpose: Notice This document does not represent the agreed views of the IEEE 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 Patent Policy: The contributor is familiar with the IEEE-SA Patent Policy and Procedures: and. 7.html#6http://standards.ieee.org/guides/opman/sect6.html#6.3 Further information is located at and.

Scope Resolve the harmful interference by coordinated scheduling in a Coexistence Frame (CX-Frame) –FDD / TDD collocated systems Examples: –LTE FDD / TDD – FDD / TDD –TDD / TDD systems using different frame durations Examples: –LTE – / in adjacent frequency bands

Interference scenarios SS to SS –Most problematic case: Small separation distance between SSs, because the RF filters may be inefficient or inexistent for SSs operating in adjacent frequency channels or frequency bands. SS to BS/Relay –Most problematic case: Small cell deployments, where the distance between a foreign SS and a BS might be small. BS/Relay to BS/Relay –Most problematic case: Co-located TDD-FDD wireless networks (WCDMA and m or LTE and ) or un-sync TDD (LTE and m). BS/Relay to SS –Most problematic case: in small cell deployments, where the distance between a foreign SS and a BS might be small.

Basic principles Time separation of the interfering radios –One works, the other is silent Protected allocation –Implies Frame synchronization Not everything interference with everything –Licensed bands –Large cell sizes Statistical probability of harmful interference is reduced –Un-protected allocations Used in common

Simplest approach to resolve FDD LTE and TDD interference Operational time of each network: 50% Resolves all the possible scenarios Protected allocation #1 FDD LTE CCXF SilenceProtected allocation #2 FDD LTE Silence m Frame 4 (TDD) LTE Frame (FDD) Protected allocation #1 16m TDD SilenceProtected allocation #2 16m TDD 16m Frame 1 (TDD) 16m Frame 2 (TDD) 16m Frame 3 (TDD)

Improved spectral efficiency to resolve FDD LTE and TDD interference Operational time of each network: 75% Resolves all the possible scenarios within the protected allocations Protected allocation FDD LTE CCXF SilenceUn-protected allocation FDD LTE Silence m Frame 4 LTE Frame Protected allocation 16m TDD Un-protected allocation TDD 16m Frame 1 16m Frame 2 16m Frame 3 57

Resolving only BS-BS and SS-SS interference Medium occupancy: 80% for the FDD BS, 70% for the FDD SS and 100% for TDD BS and SS

Silence is inserted only for FDD SS Resolving only SS-SS interference LTE FDD / TDD

Protected allocation #1 FDD BS Tx, MS Rx CCXF Un-protected allocation #1 FDD BS Tx/SS Rx Un-protected allocation #2 FDD Protected allocation #1 16m TDD Un-protected allocation #1 TDD Protected allocation #2 16m TDD Un-protected allocation #2 TDD 16m Frame 4 BS Tx, SS Rx 16m Frame 1 BS Tx, SS Rx 16m Frame 2 BS Tx, SS Rx 16m Frame 3 BS Tx, SS Rx Frame MS Tx FDD, BS Tx, SS Rx FDD, SS Tx, BS Rx Protected allocation #2 FDD BS Tx, SS Rx Protected allocation #1 FDD SS Tx, BS Rx Un-protected allocation #1 FDD BS Tx/SS Rx Silence Protected allocation #2 FDD SS Tx, BS Rx Un-protected allocation #2 FDD BS Tx/SS Rx Silence FDD, BS Tx, SS Rx FDD, SS Tx, BS Rx 16m Frame 4 BS Tx, SS Rx 16m Frame 2 BS Tx, SS Rx 16m Frame 4 BS Tx, SS Rx 16m Frame 2 BS Tx, SS Rx 16m Frame 1 SS Tx 16m Frame 3 SS Tx Silence 16m Frame 1 BS Tx, SS Rx 16m Frame 3 BS Tx, SS Rx TDD Resolving only SS-SS interference FDD / TDD

LTE TDD/ TDD Most of the operation time is protected –Was used LTE TDD config. 4 (10ms, 2 slots UL, 7 slots DL, 1 slot sync.) CCXF 16m Frame 4 BS Tx, SS Rx LTE TDD Frame, Config. 4 BS Tx, SS Rx SS Tx, BS Rx Protected allocation #1 SS Tx, BS Tx BS Rx, SS Rx LTE and m MS Tx Frame 3 SF0SF2SF3SF4SF5SF8SF9SF6SF7SF0SF2SF3SF4SF5SF8SF9SF6SF m Un- protected alloc. #1 16m Frame 1 BS Tx, SS Rx MS Tx Frame 4 16m Frame 2 BS Tx, SS Rx MS Tx Frame 1 MS Tx Frame 2 Protected allocation #2 SS Tx, BS Tx BS Rx, SS Rx LTE and m BS Tx Fr 3 Un-protected allocation #2 16m only protected alloc.

Cognitive information related to CCXF CCXF has elements of cognitive information –periodicity of the CCXF: 20ms –duration and position of the intervals allocated for the TDD protected operation (relative to CCXF start) –DL/UL split (if it is permanent, can be known). An un-synchronized system can use the cognitive information related to the CCXF structure at its location for achieving synchronization TDD systems are the best positioned to use the cognitive properties of the CXCF, due to the reciprocity the medium: for example, if and SS creates interference to another SS, it will also be an interference victim FDD SS will suffer from receiver blocking in a large part of the band –The RF filters are not sharp enough

Harmful TDD interference experienced by SS within un-synchronized FDD network Blue areas show the super-position of the SS receive slots affected by interference

Text for SDD In C802.16m/08-604