January 2008doc.: IEEE 802.22-08/0003r0
IEEE P802.22
Wireless RANs
Date: 2008-01-08
Author(s):
Name / Company / Address / Phone / email
William Rose / WJR Consulting Inc. / 3 Tunxis Road, West Hartford CT 06107 / 860 313 8098 /
Patent Policy Notification:
Please Note the IEEE Patent Policy can be found at:
- The IEEE’s patent policy is consistent with the ANSI patent policy and is described inClause 6 of the IEEE-SA Standards Board Bylaws.
- It is important to provide early identification of patent claims which may be essential for the use of any standards under development by this Task Group. There may be Essential Patent Claims of which the IEEE is not aware.
- Additionally,neither the IEEE, the WG, nor the WG or TG chairs can ensure the accuracy orcompleteness of any assurance or whether any such assurance is, in fact, of aPatent Claim that is essential for the use of the standard under development.
- Introductions
- Patent policy review
- Approve agenda
- Approve minutes from 1/03/08
- Comment Resolution:
- Address Comment 108
“This comment was rejected in Draft 1.0 as CID #187. I contributed a "Suggested Remedy" that the resolver(s) did not want to implement. However, the problem still exists, so I will restate the problem and ask that a resolution be proposed.
I upgrade the original "Comment" base on new information on detecting MSF2 and MSF3 (and update references and subclause numbers) as follows:
Referring to the entire subclause "5.6 Beacon frame structure" and the associated Figure 6, the 3 MAC subframes (MSF1-MSF3) are 17, 51, and 33 octets, respectively. When the 1/2-rate BCC encoding is applied to MSF1, and the 12 tail bits are added and then 12 bits punctured, the length of the encoded MSF1 becomes 34 octets, bringing the lengths of the 3 subframes to 34, 51, and 33 octets respectively.
We learn in 6.7.1.6 "Chip and bit rates" that because 1/140 * the ATSC symbol rate is used, the bit rate for transmissioin is approximately 9.6091 kbit/s = 1201.14 kbyte/s.
For the 3 subframes, this translates to 28.3msec, 42.5msec, and 27.5msec, respectively. But to read MSF2 correctly, MSF1+MSF2 must be read. And to read MSF3 correctly, MSF1+MSF2+MSF3 must be read. Therefore the three windows sizes requried to read the 3 frames are 28.3msec, 70.8msec, and 98.0msec (not including header).
Because the integrity of the reception of the subframes relies on the CRC field, the subframes must be received in their entirety. When the 802.22 WRANs are allocating quiet periods in integral number of frames, this implies that the quiet periods must be the multiple of 10ms that is greater than the subframe duration plus 10ms because of misalignment. This means the WRAN must allocate 40msec, 90msec, and 110msec, respectively to capture these subframes.
I think that means that if any node in the WRAN system senses the Beacon synchronization bursts, it is hopeless for the WRAN system to allocate quiet periods to read the MSF fields and maintain QoS. Either we should find a remedy or the WRAN 802.22 document for "Spectrum Manager" should state that after sensing the 802.22.1 beacon, vacate the channel.
While it is necessary to successfully receive only MSF1 to know that a beaconing device licensed or illegitimate jammer) are present, this implies that the WRAN must allocate a minimum of a 40msec window to receive the beaconing device's MSF1. This quiet period duration is too long for VoIP applications by a factor of two." - Comment 123
The term "subchannel" will be used in the 802.22 standard and will have a totally different meaning in the OFDM context. - Comment 491
The requirement for unlicensed devices to decode the beacon sub frames should apply only to WRAN or similar networks whose transmit range is much greater than the sensing range
- Continue to resolve TRs followed by Ts.
- Open Business
- Next Meetings
- Face to Face Meetings: Taipei, Taiwan: January 14th – 18th
- Adjourn
Submissionpage 1William Rose, WJR Consulting Inc.