Amer Hassan, Jan Kruys, Jim Raab, Stefan MangoldSlide 1Submission May 2004doc.: IEEE Spectrum Etiquette Rules for Shared and Unlicensed Bands Amer Hassan, Microsoft Jan Kruys, Cisco Jim Raab, Dell Stefan Mangold, Philips

May 2004 Amer Hassan, Jan Kruys, Jim Raab, Stefan MangoldSlide 2 doc.: IEEE Submission Purpose IEEE SG1 is approaching the FCC with recommendations regarding the unlicensed use of TV-bands and other fallow spectrum A task group was formed in summer 2003 in the Wi-Fi Alliance to address spectrum sharing Ensure license exempt spectrum usable with good user experience with the rapid increase of licensed exempt devices across all market segments & products It is very important that such recommendations have a solid basis in research and modeling Industry should provide the right direction to international regulators in this early stage of discussion Simple sharing rules are discussed in the following

May 2004 Amer Hassan, Jan Kruys, Jim Raab, Stefan MangoldSlide 3 doc.: IEEE Submission Solutions in Four Domains Frequency, Space, Time, Information Information Frequency TimeSpace/Power Wireless LAN UWB LW bdcst CDMA Time beacon UMTS

May 2004 Amer Hassan, Jan Kruys, Jim Raab, Stefan MangoldSlide 4 doc.: IEEE Submission Possible Solutions to Spectrum Etiquette Improving Receivers Filtering Modulation and Coding Antenna Diversity, MIMO Improving Transmitter Modulation & Coding Power Constraints Antenna Pattern Listen-before Talk (LBT) Sample spectrum etiquette rules are discussed in the following … Improving Wireless System Power/Time constraints Frequency selection Feedback from the receiver Hybrid Methods

May 2004 Amer Hassan, Jan Kruys, Jim Raab, Stefan MangoldSlide 5 doc.: IEEE Submission Be Nice and Efficient Non-Greedy Occupancy No user may occupy the channel with rate 0 (no data to send): RULE#1: A device shall only transmit when it has data to send Channel Selection A channel is deemed accessible at a node if the aggregate interference power at the intended receiver is less than I TH : RULE#2: A device shall only transmit on a channel if the aggregate interference power for that channel as measured at the intended receiver is less than I TH

May 2004 Amer Hassan, Jan Kruys, Jim Raab, Stefan MangoldSlide 6 doc.: IEEE Submission RULE#1 Simulation Results (Out/Indoor) average number of blocked nodes, as function of number of greedy nodes even 1 greedy node blocks the channel at an average of 4 nodes outdoors and 24 nodes indoors 10 of the nodes greedy blocks an average of 41% of the nodes outdoors and 98% indoors number of nodes blocked at least 90% in time, as function of number of greedy nodes 10 of the nodes greedy blocks 33% of the nodes outdoors and 93% indoors at least 90% of the time a small fraction of greedy nodes can block channel access for the majority outdoor indoor

May 2004 Amer Hassan, Jan Kruys, Jim Raab, Stefan MangoldSlide 7 doc.: IEEE Submission a new active link with RULE#2 results in a slight reduction in clear links compared to the background case a new active link w/o RULE#2 results in a more significant reduction in clear links compared to both the background and the RULE#2 cases RULE#2 Simulation Results average number of clear (not blocked) links for four scenarios Outdoor propagation model with low background interference Outdoor propagation with high background interference Indoor propagation with low background interference Indoor propagation with high background interference For each scenario the average number of clear links is shown with background interference only, with new active link, with and w/o channel check (RULE#2) With RULE#2 W/O RULE#2

May 2004 Amer Hassan, Jan Kruys, Jim Raab, Stefan MangoldSlide 8 doc.: IEEE Submission Left: without etiquette, right: with etiquette Apparently, it would be beneficial to the broadband radio systems if the narrowband radio systems would select channels according to the etiquette Frequency Selection Uncoordinated channel selectionSpectrum efficient behavior (etiquette)

May 2004 Amer Hassan, Jan Kruys, Jim Raab, Stefan MangoldSlide 9 doc.: IEEE Submission Conclusions It is important that we work together as industry to improve the usage of unlicensed spectrum We demonstrated simple rules that significantly improve the usage of such spectrum Thorough evaluation is already under way at SG1 and Wi-Fi Alliance Such evaluation is needed prior to approaching regulators