1. Regulatory Information for Low Latency Scanning in 5 GHz bands
November 2003
doc.: IEEE /973r0
July 2004
Regulatory Information for Low Latency Scanning in 5 GHz bands
Amjad Soomro, Zhun Zhong and Javier Del Prado
Philips
Soomro et. al., Philips
Soomro et. al., Philips

2. European Regulations in 5 GHz Bands
July 2004
European Regulations in 5 GHz Bands
For any STA, before transmitting on a channel
Detect radars
Know maximum transmit power levels
Apply transmit power mitigation, if applicable
However, STAs are allowed to rely on measurements and ‘Mitigation’ requirements announced by AP
Soomro et. al., Philips

3. Situation Results in long scan times
July 2004
Situation
STAs are forced to do passive scanning while roaming in 5 GHz bands in European regulatory domains
Similar requirements might become applicable in US in upper 5 GHz bands
Limits on maximum transmit power might be desirable for administrative reasons where regulatory requirements do not exist
Passive scanning may result in wait times of up to one beacon period per scanned channel
5 GHz bands has at least twelve channels
Many more to be available in future (US)
Results in long scan times
Soomro et. al., Philips

4. Proposal 1 Include regulatory information in Site Report
July 2004
Proposal 1
Include regulatory information in Site Report
Enables active scanning
Specifically, include additional four bytes
Maximum Transmit Power Level
Local Power Constraint
Map field (as defined in h amendment)
Information supplied by neighboring AP’s
Maximum Transmit Power Level
Local Power Constraint
Map
Octets 1 2
Soomro et. al., Philips

5. Proposal 2 Site Reports may not be always available.
July 2004
Proposal 2
Site Reports may not be always available.
No neighbor information available
APs may choose to not include neighbor information
Soomro et. al., Philips

6. July 2004
Proposal 2
Add capability for APs to transmit regulatory information in between beacons
Define new Regulatory Domain Information frame
The frame to be transmitted, autonomously, by an AP in between beacons, zero or more times.
Category
Action
Dialog Token
Regulatory Domain Information Element
Octet: 1 5
Figure 0-6 – Regulatory Domain Information frame body format
Element ID
Length
Maximum Transmit Power Level
Local Power Constraint
Map/Detected Signal Map
Octets: 1
Figure 1— Regulatory Domain Information Element field format
Soomro et. al., Philips

7. July 2004
Field Definitions
The definitions for Maximum Transmit Power Level, Local Power Constraint and Map are the same as defined in IEEE h amendment.
Soomro et. al., Philips

8. Benefits Beacons have lots of other information
July 2004
Benefits
Beacons have lots of other information
Regulatory Domain Information frame keeps the frame length small
Efficiently announces regulatory domain information, making it easier to transmit it multiple times within a beacon interval
Reduces Passive Scanning Times
By enabling on-demand active scanning
Measurements Results/Information already exists in AP/neighboring APs
No additional measurement burden – just reporting
No hardware changes required
Soomro et. al., Philips

9. Comparison Table for Two Proposals
July 2004
Comparison Table for Two Proposals
Site Report
Regulatory Domain Frame
Benefit at Initial Start up while passive scanning No
Yes
Dependent on Neighbor Information Available
Channel Information Supplied
Current Channel
Other Channels
Benefit while operating in the same channel
Benefit when moving to a different channel
The two proposals are complementary
Soomro et. al., Philips

10. July 2004
Conclusions
Only passive scanning possible with the current protocol in 5 GHz European bands
The proposal
Enables active scanning
Reduces time spent in passive scanning
Simple additions in the protocol
Without hardware changes
Soomro et. al., Philips

11. July 2004
Straw Poll 1
Would you support including regulatory information in Site Report to enable active scanning
YES NO
Soomro et. al., Philips

12. July 2004
Straw Poll 2
Would you support adding a protocol frame to report regulatory information/measurements
YES NO
Soomro et. al., Philips

13. July 2004
Motion 1
Instruct the editor to incorporate changes submitted in the document in the next TGk draft
Soomro et. al., Philips

14. July 2004
Motion 2
Instruct the editor to incorporate changes submitted in the document in the next TGk draft
Soomro et. al., Philips