1. Amendment Proposal for TV White Spaces Operation
Month Year
doc.: IEEE yy/xxxxr0
Amendment Proposal for TV White Spaces Operation
Date: April 13, 2010
Authors:
Name
Company
Address
Phone
Eunsun Kim
LG Electronics
Mobile Comm. Lab, LG R&D Complex 533, Hogye1, Dongan, Anyang, Korea
Yongho Seok
Mobile Comm. Lab, LG R&D Complex 533, Hogye1, Dongan, Anyang , Korea
Soonjoon Park
John Doe, Some Company

2. Introduction The technical issues raised in this proposal
Scanning Issue
Slide 2

3. Scanning Number of scanning channels in TVWS
The candidate channels are almost 30 (=180MHz/6MHz) when one channel bandwidth is 5 MHz
Considering 10MHz/20MHz channel bandwidth, the number of channels that STA should scan are tripled (around 90).
Large initial access delay of Passive Scanning
Scanning time might be around 9,000ms
i.e., 3 (Number of candidate bandwidth) x 30 (Number of candidate channels) x 100ms (Beacon Interval)
Power consumption
Power consumption depends on the number of scanning channels
Submission
Slide 3

4. Accelerate Contribution
November 2009
Accelerate Contribution
Scanning
Multi-band mode
STA can use other links and TVWS link as well as a control link to discover AP and get the TVWS MAP information
White Space Map specifies the channel list unoccupied by the primary users
They can be a/b/g/n/cellular link or TVWS link
TVWS MAP transmission
Within beacon frame
Within response frame requested by STA
Can be transmitted in a/b/g/n/cellular or TVWS link
LG Electronics, Inc.

5. Accelerate Contribution
November 2009
Accelerate Contribution
Scanning
Multi-band mode
Coverage difference between other links and TVWS link
Due to carrier frequency characteristics
There are often coverage holes of 2.4GHz WLAN
Relative link budget difference is around 9~12dB (TVWS link vs. 2.4GHz link)
Due to System parameter
TVWS
2.4GHz link
Channel bandwidth
5MHz
20MHz
Guard Interval
3.2us
0.8us
Maximum transmission power
100mW
Relative Power Spectral density 1
0.25
LG Electronics, Inc.

6. Accelerate Contribution
November 2009
Accelerate Contribution
Scanning
Multi-band mode
- Seamless WLAN service
LG Electronics, Inc.

7. Scanning Cold Start mode Warm Start mode
In a very initial state, or after certain elapsed time, in which STAs do not have TVWS channel information, STAs scan whole TVWS channels
Or STAs get TVWS channel information from other than TVWS link
Warm Start mode
STAs scan TVWS channels from the last operation with available TVWS channel list, i.e. warm start mode
STAs need not always scan whole TVWS channels
STAs need not receive control information via 2.4GHz/5GHz link
In a warm start mode, STA shall scan TVWS channels based on TVWS information received from AP during last operation

8. Scanning White space map within Beacon Frame
White space map is provided by beacon frame
White Space Map specifies the channel list unoccupied by the primary users
Once STA listens to beacon frame, STA doesn’t need to scan channels occupied by incumbent users
By skipping the channels occupied by incumbent users , initial access delay and power consumption problem can be resolved a little.
However, it can be some overhead for beacon frame.
Submission
Slide 8

9. Accelerate Contribution
November 2009
Accelerate Contribution
Scanning
White space map within Response Frame
AP provides White Space Map information to STA for reducing the scanning overhead
White Space Map is transmitted within Response Frame
Response frame can be probe response frame
LG Electronics, Inc.

10. Normative Text Summary
November 2009
Accelerate Contribution
Normative Text Summary
Introducing White Space Map
Provide a list of identified available channels and its maximum allowed transmission power
STAs should scan the identified available channels based on the WSM
APs and STAs should generate WSM based on TV channel information from TV bands database or its own spectrum sensing 
LG Electronics, Inc.

11. Normative Text Summary
November 2009
Accelerate Contribution
Normative Text Summary
Introducing Multi-band IE
Assume that an AP and STAs have multiple radios for different bands
Provides AP’s operating channel numbers and its corresponding regulatory classes
STAs receiving Multi-band Operation element are able to discover the AP operating in different bands without channel switches
LG Electronics, Inc.