However, in the interests of compromise, the IEEE 802.11 Working recommends that reasonable restrictions be placed on the use of blocking energy by all devices in the next revision of EN 301 893 rather than a complete ban, and that these restrictions be defined in a way that are applicable to all technologies. This approach will uphold the important principle of technology neutrality. In particular, IEEE 802.11 Working Group recommends that, in the next revision of EN 301 893, a device only be allowed to transmit energy for a maximum of 100 µs when the primary purpose of that transmission is to block another user from accessing the channel. In the context of LAA, this would mean that an LAA device would only be able to transmit blocking energy for a maximum of 100 µs before a starting position. Noting that an LAA symbol has a length of about 71 µs, this would allow LAA to operate with a starting position at each of the fourteen symbols in a sub-frame. While this different from how LAA currently operates today, a recent contribution to 3GPP RAN1 suggests this is a feasible compromise solution to resolve the blocking energy issue. The effect of such a rule be to force LAA to define fourteen mandatory starting positions if 3GPP RAN1 decided that it is important to enable the use of blocking energy. Of course, 3GPP RAN1 could always decide not to enable the use of blocking energy because, as they noted previously, deferring sending energy until a subframe boundary or partial subframe boundary … also provided good LAA performance. The IEEE 802.11 Working Group requests that ETSI BRAN consider our recommendation to restrict the use of blocking energy. We would be delighted to have further discussions with ETSI BRAN in relation to this topic. Sincerely, Adrian Stephens IEEE 802.11 Working Group
However, in the interests of compromise, the IEEE 802.11 Working recommends that reasonable restrictions be placed on the use of blocking energy by all devices in the next revision of EN 301 893 rather than a complete ban, and that these restrictions be defined in a way that are applicable to all technologies. This approach will uphold the important principle of technology neutrality. In particular, IEEE 802.11 Working Group recommends that, in the next revision of EN 301 893, a device only be allowed to transmit energy for a maximum of 100 µs when the primary purpose of that transmission is to block another user from accessing the channel. In the context of LAA, this would mean that an LAA device would only be able to transmit blocking energy for a maximum of 100 µs before a starting position. Noting that an LAA symbol has a length of about 71 µs, this would allow LAA to operate with a starting position at each of the fourteen symbols in a sub-frame. While this different from how LAA currently operates today, a recent contribution to 3GPP RAN1 suggests this is a feasible compromise solution to resolve the blocking energy issue. The effect of such a rule be to force LAA to define fourteen mandatory starting positions if 3GPP RAN1 decided that it is important to enable the use of blocking energy. Of course, 3GPP RAN1 could always decide not to enable the use of blocking energy because, as they noted previously, deferring sending energy until a subframe boundary or partial subframe boundary … also provided good LAA performance. The IEEE 802.11 Working Group requests that ETSI BRAN consider our recommendation to restrict the use of blocking energy. We would be delighted to have further discussions with ETSI BRAN in relation to this topic. Sincerely, Adrian Stephens IEEE 802.11 Working Group
11-17-1393-01-coex-proposed-liaison-statement-to-etsi-bran-in-relation-to-blocking-energy-issues.docx