10018H -TGh Proposal for Transmitter Power Control (TPC) Month 2000 doc.: IEEE 802.11-01/001 January 2001 10018H -TGh Proposal for Transmitter Power Control (TPC) Christopher J. Hansen, Matthew Fischer, Rajugopal Gubbi, Joonsuk Kim Broadcom Corporation Hansen, Fischer, Gubbi, and Kim, Broadcom Corporation C. Hansen, Broadcom Corporation

Outline Background 802.11a PHY Modifications 802.11 MAC Modifications Month 2000 doc.: IEEE 802.11-01/001 January 2001 Outline Background 802.11a PHY Modifications 802.11 MAC Modifications TPC Operation Summary Hansen, Fischer, Gubbi, and Kim, Broadcom Corporation C. Hansen, Broadcom Corporation

January 2001 Background TPC is a requirement for operation on the 5 GHz band in Europe TPC will also improve network performance by reducing interference. Small additions to the 802.11a PHY and 802.11 MAC standards will allow interoperable networks to meet both goals. Hansen, Fischer, Gubbi, and Kim, Broadcom Corporation

January 2001 Background We define only the PHY and MAC changes necessary to implement TPC algorithms that will meet the ERC requirements. Actual algorithms are implementation dependent. Hansen, Fischer, Gubbi, and Kim, Broadcom Corporation

802.11a PHY Modifications Will changes to the PHY help TPC? Yes! January 2001 802.11a PHY Modifications Will changes to the PHY help TPC? Yes! Standardize power settings for TPC minimize interference and maintain interoperability Hansen, Fischer, Gubbi, and Kim, Broadcom Corporation

802.11a PHY Modifications Absolute TX Power Settings for all STAs January 2001 802.11a PHY Modifications Absolute TX Power Settings for all STAs -15 dBm to +30 dBm, 3 dB steps 16 settings; 4 bit representation Closely follows ETSI Hiperlan/2 AP_Tx_Level Hansen, Fischer, Gubbi, and Kim, Broadcom Corporation

January 2001 802.11 MAC Modifications TPC information is exchanged with Probe request and Probe response frames Probe Request frame format Hansen, Fischer, Gubbi, and Kim, Broadcom Corporation

802.11 MAC Modifications Corresponding Probe response frame January 2001 802.11 MAC Modifications Corresponding Probe response frame Hansen, Fischer, Gubbi, and Kim, Broadcom Corporation

January 2001 802.11 MAC Modifications Probe response fixed fields repeat previously received values from AP/PC Copy fields from last received beacon We define new element for TPC TPC power setting request/response Hansen, Fischer, Gubbi, and Kim, Broadcom Corporation

802.11 MAC Modifications TPC power setting request element January 2001 802.11 MAC Modifications TPC power setting request element Command flag bit: 0 for tell me your power level; 1 for set your power to the level setting TX power level setting (see PHY Section) Element ID Length Flag TX Power Level Octets: 1 Hansen, Fischer, Gubbi, and Kim, Broadcom Corporation

802.11 MAC Modifications TPC power setting response element January 2001 802.11 MAC Modifications TPC power setting response element TX power setting Element ID Length TX Power Level Octets: 1 Hansen, Fischer, Gubbi, and Kim, Broadcom Corporation

January 2001 802.11 MAC Modifications Global TPC status information is conveyed in the Beacon Frame Hansen, Fischer, Gubbi, and Kim, Broadcom Corporation

802.11 MAC Modifications Global TPC Status element defines: January 2001 802.11 MAC Modifications Global TPC Status element defines: Maximum TX power in the BSS Element ID Length Max TX Power Setting Octets: 1 1 1 Hansen, Fischer, Gubbi, and Kim, Broadcom Corporation

January 2001 TPC Operation Power levels can be controlled in both a centralized and a distributed fashion AP can use global TX power limit within BSS STAs can request power level changes from other STAs AP (and STAs) can individually set power level for each destination STA Hansen, Fischer, Gubbi, and Kim, Broadcom Corporation

January 2001 TPC Operation Standardized power settings allow consistency of operation in a network with different STA implementations AP can guarantee ERC Requirements are met TPC can be made fair Hansen, Fischer, Gubbi, and Kim, Broadcom Corporation

Summary We propose that TGh consist of the following: January 2001 Summary We propose that TGh consist of the following: 802.11a TX power level standardization 802.11 MAC Probe request/response elements for TPC Each STA being able to send probe request/response frames to another STA in the BSS Hansen, Fischer, Gubbi, and Kim, Broadcom Corporation