1. Acknowledgment for CBP transmission
July 2007
doc.: IEEE yy/xxxxr0
May 2008
Acknowledgment for CBP transmission
IEEE P Wireless RANs Date:
Authors:
Notice: This document has been prepared to assist IEEE It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) 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 and Procedures: The contributor is familiar with the IEEE 802 Patent Policy and Procedures including the statement "IEEE standards may include the known use of patent(s), including patent applications, provided the IEEE receives assurance from the patent holder or applicant with respect to patents essential for compliance with both mandatory and optional portions of the standard." Early disclosure to the Working Group of patent information that might be relevant to the standard is essential to reduce the possibility for delays in the development process and increase the likelihood that the draft publication will be approved for publication. Please notify the Chair
Carl R. Stevenson as early as possible, in written or electronic form, if patented technology (or technology under patent application) might be incorporated into a draft standard being developed within the IEEE Working Group. If you have questions, contact the IEEE Patent Committee Administrator at
>
Sangbum Kim, Samsung Electronics

2. May 2008
Introduction
CBP packet is used for inter-WRAN communication and it includes information for self-coexistence;
According to the CBP design in D1.0, hidden node problem still exists, which may degrades the performance of self-coexistence mechanisms/algorithms relying on CBP transmission;
A new CBP acknowledgment is proposed for remedy;
Sangbum Kim, Samsung Electronics

3. Review on CBP Transmission Procedure
May 2008
Review on CBP Transmission Procedure
BS schedules a SCW in active mode according to a regular pattern.
During its initialization stage, a new comer WRAN monitors the channel to discover neighboring WRANs and identifies their SCW regular patterns.
The WRAN shall set its own regular pattern so that is does not overlap with the SCWs reserved by the discovered neighboring WRAN
Sangbum Kim, Samsung Electronics

4. Collision scenario 1: between a new comer cell and an existing cell
May 2008
Collision scenario 1: between a new comer cell and an existing cell
A new comer BS0 first learns the pattern for SCW scheduling of BS1.
However, BS0 may not know the existence of BS2 which is far away from BS0.
It’s possible that BS0 chooses a SCW slot which is actually used by BS2 as active SCW slot.
Then collision between two CBPs from BS0 and BS2 may occur at CBP receivers in BS1's cell.
This is most significant when the CBPs are being received by BS1
Sangbum Kim, Samsung Electronics

5. Collision scenario 2: between new comer cells
May 2008
Collision scenario 2: between new comer cells
Two new comer BS0 and BS2 learn the pattern for SCW scheduling of BS1.
However, BS0 and BS2 may not know the each other’s existence.
It’s possible that BS0 and BS2 choose the same SCW slot.
Then collision between two CBPs from BS0 and BS2 may occur at CBP receivers in BS1's cell.
Sangbum Kim, Samsung Electronics

6. Acknowledgment for CBP transmission
May 2008
Acknowledgment for CBP transmission
Destination cell should transmit an acknowledgment for CBP packets received from neighboring WRAN cells when requested.
The ACK is delivered through the destination cell’s CBP packet.
Neighboring cells can then know whether their CBPs are successfully transmitted or not.
If neighboring cells don’t receive the ACK, they assume CBP collisions have occurred and then try another SCW opportunity for CBP transmission.
Acknowledgment allows to get away from collision situation quickly.
Sangbum Kim, Samsung Electronics

7. Additional IE format & CBP ID
May 2008
Additional IE format & CBP ID
CBP_ACK
A new IE at least include CBP_ID of received CBP packet
In the response of received CBP packets, destination BS sends CBP_ACK through CBP packet
CBP_ACK includes CBP_IDs of CBP packets received successfully
CBP_ID
CBP_ID is included only when the source BS needs a ACK
When the source BS receives no ACK and it needs to switch to another slot, it then regenerate the CBP_ID
CBP_ID generation
Combination of BS MAC address and random value
E.g.
Sangbum Kim, Samsung Electronics

8. Procedure for acknowledgment
May 2008
Procedure for acknowledgment
Sangbum Kim, Samsung Electronics

9. An example Scenario CBP transmissions May 2008
Sangbum Kim, Samsung Electronics

10. CBP_ACK IE format May 2008 Syntax Size Notes CBP_ACK_format() {
CBP_IDs
variable
CBP_ID list of CBP packet received successfully }
Sangbum Kim, Samsung Electronics

11. May 2008
References
IEEE P802.22™/ WDv0.4.8, Draft Standard for Wireless Regional Area Networks Part 22: Cognitive Wireless RAN Medium Access Control (MAC) and Physical Layer (PHY) specifications: Policies and procedures for operation in the TV Bands
Sangbum Kim, Samsung Electronics