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TGh Monitored Signal Strength Indication (MSSI)
January 2001 TGh Monitored Signal Strength Indication (MSSI) Peter Ecclesine Cisco Systems Peter Ecclesine, Cisco Systems
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Real approval comes from spectrum holders
January 2001 Real approval comes from spectrum holders The real requirement is interference avoidance; for us to detect weak licensed users, and avoid that channel Regardless of current regulatory situation, the licensed users of the band will prevail Peter Ecclesine, Cisco Systems
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Month 2000 doc.: IEEE /xxx January 2001 RSSI definitions RXVECTOR.RSSI defined in PMD_RSSI.indicate defined in as an octet continually available in the receive state some DS primitives are not defined in .11a PMD_SQ.indicate, PMD_CS.indicate, PMD_ED.indicate, indicates receive energy greater than the ED_THRESHOLD Peter Ecclesine, Cisco Systems John Doe, His Company
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RSSI definitions (con’t)
Month 2000 doc.: IEEE /xxx January 2001 RSSI definitions (con’t) RSSI shall be a measure of the RF energy received by the OFDM PHY. RSSI indications of up to 8-bits (256 levels) are supported. [It] shall be generated by the PMD when the OFDM PHY is in the receive state. is in the receive state when PHY_TXSTART.request is disabled. Upon receiving the transmitted PLCP preamble, PMD_RSSI.indicate shall report a significant received signal strength level .. Peter Ecclesine, Cisco Systems John Doe, His Company
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CCA definitions 17.3.6 Clear Channel Assessment refers to:
January 2001 CCA definitions Clear Channel Assessment refers to: CCA sensitivity A start of a valid OFDM transmission at receive level greater than minimum 6 Mbit/s sensitivity (-82dBm) shall cause CCA to indicate Busy with probability > 90% within 4us. If the preamble portion is missed, the receiver shall hold the CS signal Busy for any signal 20dB above minimum 6 Mbit/s sensitivity (-62dBm). Peter Ecclesine, Cisco Systems
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Need to create a MONVECTOR
January 2001 Need to create a MONVECTOR Require, at least, the same measurement periods as HiperLAN/2, to ease regulatory acceptance. This is up to 63 2 msec ‘frames’. Recommend a new PLME-SAP vector for monitoring over an extended time, relative to data traffic. May have a lower resolution RSSI/MSSI circuit to use less power while monitoring a channel May want to monitor the active channel (e.g. the channel used by the station to communicate) to detect energy other than valid received frames – like inter-BSS interference, so MSSI measurement would span the transmission and reception of many frames RXVECTOR can serve for receiving valid frames on a monitored channel Peter Ecclesine, Cisco Systems
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MSSI directly relates to RSSI
January 2001 MSSI directly relates to RSSI MSSI shall be a measure of the RF energy received by the OFDM PHY. MSSI indications of up to 8-bits (256 levels) are supported. MSSI shall be generated by the PMD when the OFDM PHY is in the receive state. MSSI measurement is made with the same PHY apparatus that measures RSSI, however PMD_MSSI.indicate shall be true for any receive level greater than minimum 6 Mbit/s sensitivity (-82dBm) with probability > 90% within 4us., regardless of it being a preamble. Peter Ecclesine, Cisco Systems
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MSSI directly relates to RSSI (con’t)
January 2001 MSSI directly relates to RSSI (con’t) HiperLAN/2 Short, Percentiles and Complete kinds of measurements can be constructed from PMD_MSSI.indicate samples, but we need to decide what aids licensed user interference avoidance. Peter Ecclesine, Cisco Systems
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