1. Below 6GHz 11vht PAR scope and purpose discussion
March 2008
doc.: IEEE /0219r4
March 2008
Below 6GHz 11vht PAR scope and purpose discussion
Date:
Authors:
Courville (Motorola), Kraemer (Marvell), Engwer (Nortel), De Vegt (Qualcomm), Erceg (Broadcom)
Marc de Courville (Motorola)

2. March 2008
doc.: IEEE /0219r4
March 2008
PAR: scope (initial)
The scope of this project is to define an amendment that shall define standardized modifications to both the physical layers (PHY) and the Medium Access Control Layer (MAC) so that modes of operation can be enabled that are capable of supporting:
A multi-user BSS peak aggregated throughput of at least 1Gbps as measured at the MAC data service access point (SAP)
Capability of handling multiple communications at the same time
Below 6GHz carrier frequency operation excluding 2.4GHz operation and ensuring backward compatibility and coexistence with legacy IEEE802.11a/n devices in the 5GHz unlicensed band.
Courville (Motorola), Kraemer (Marvell), Engwer (Nortel), De Vegt (Qualcomm), Erceg (Broadcom)
Marc de Courville (Motorola)

3. PAR: scope. Evolution discussion
March 2008
doc.: IEEE /0219r4
March 2008
PAR: scope. Evolution discussion
See also companion 08/0464r1 presentation related to relevant metrics to consider for rate target specification
Shall the throughput constraint be applied only to the AP (non always existing entity: IBSS)?
Change to BSS or IBSS capacity (ambiguity between different types e.g. Shannon etc.)? Recommendation: remain with throughput metric
Specifying aggregated or multi-user is necessary in the IBSS case whereas for the BSS case we could apply the metric to the AP
Shall we revert to a per link metric? Discussions are converging a more global network one
Shall we capture OBSS, ESS (mesh), multiple IBSS/BSS? Recommendation: keep it simple at least for PAR and possibly increase in complexity for the Comparison Criteria
Courville (Motorola), Kraemer (Marvell), Engwer (Nortel), De Vegt (Qualcomm), Erceg (Broadcom)
Marc de Courville (Motorola)

4. New PAR: scope proposal
March 2008
doc.: IEEE /0219r4
March 2008
New PAR: scope proposal
The scope of this project is to define an amendment that shall define standardized modifications to both the physical layers (PHY) and the Medium Access Control Layer (MAC) so that modes of operation can be enabled that are capable of supporting:
A maximum BSS or multiuser IBSS throughput of at least 1Gbps as measured at the MAC data service access point (SAP)
Capability of handling multiple communications at the same time
Below 6GHz carrier frequency operation excluding 2.4GHz operation and ensuring backward compatibility and coexistence with legacy IEEE802.11a/n devices in the 5GHz unlicensed band.
Courville (Motorola), Kraemer (Marvell), Engwer (Nortel), De Vegt (Qualcomm), Erceg (Broadcom)
Marc de Courville (Motorola)

5. Straw polls SP#1: SP#2: SP#3: March 2008
Shall we capture both the BSS and IBSS case in the PAR scope?
Yes: No: Abstain:
SP#2:
Shall the multiuser aspect be present in the PAR scope wording?
SP#3:
Is changing in the PAR scope
A multi-user BSS peak aggregated throughput of at least 1Gbps as measured at the MAC data service access point (SAP) by
A maximum BSS or multiuser IBSS throughput of at least 1Gbps as measured at the MAC data service access point (SAP)
considered as a positive evolution?
Courville (Motorola), Kraemer (Marvell), Engwer (Nortel), De Vegt (Qualcomm), Erceg (Broadcom)

6. PAR: purpose Change To:
March 2008
doc.: IEEE /0219r4
March 2008
PAR: purpose
Change
The purpose of the project is to improve the wireless local area network (LAN) user experience by providing significantly higher aggregated throughput for existing WLAN application areas and to enable new market segments for operation below 6 GHz including distribution of multiple multimedia/data streams.
To:
The purpose of the project is to improve the wireless local area network (LAN) user experience by providing significantly higher BSS or multiuser IBSS throughput for existing WLAN application areas and to enable new market segments for operation below 6 GHz including distribution of multiple multimedia/data streams.
Courville (Motorola), Kraemer (Marvell), Engwer (Nortel), De Vegt (Qualcomm), Erceg (Broadcom)
Marc de Courville (Motorola)

7. Rate expectation discussion
March 2008
Rate expectation discussion
Preliminary remarks/questions:
One could think that we must go far beyond 11n max PHY rate but is this realistic for a reasonable client configuration/cost?
11a max PHY rate is achievable at (54Mbps) whereas 11n max PHY rate (600Mbps) has not been demonstrated yet: this need to be considered as a specification number.
Initially MAC SAP throughput was introduced for providing a better metric for setting users expectations but currently peak PHY throughput is still used as the marketing number on the product boxes: shall we revert the policy and come back to PHY throughput metric to define the PAR?
Some baseline reference numbers:
11a max PHY rate: 54Mbps, estimated MAC SAP rate (without aggregation, 5 users): 27Mbps (2x)
11n: max PHY rate (40MHz 4STS Short GI): 600Mbps, PAR MAC SAP target rate: min max of 100Mbps
Need to anticipate that this method could be used for PAR MAC SAP throughput expectation derivation
11a->11n PAR gap: 100/54=1.85
11n->11vht gap should thus be to match evolution rate: PAR(11vht)=PAR(11n)/max(11a)*max(11n)=1.85*600=1.11Gbps!
Reality sanity check: some rough initial MAC SAP throughput numbers extrapolated from 11n (5 users contending, 2ms TxOP AMSDU aggregation)
3ss 4x20MHz: 680Mbps, 3ss 5x20MHz: 850Mbps
2ss 4x20MHz: 450Mbps, 2ss 5x20MHz: 560Mbps
Question: limit cost of client to 2ss?
Reference 11n PHY max rate: 2ss: 130/270Mbps, 3ss 195/405Mbps for 20/40MHz
Proposed methodology for the peak aggregated BSS throughput derivation
Increase moderately PAR MAC SAP target increase evolution of 3.7x from 11a->11n to 5x for 11n->11vht: i.e. 500Mbps
Concluding remark: a reasonable PAR target will allow not to put too much constraints on entry point products and does not preclude defining multiple Gbps modes following the model introduced in 11n. The gap that is recommended to consider is on the MAC SAP rates evolution
Courville (Motorola), Kraemer (Marvell), Engwer (Nortel), De Vegt (Qualcomm), Erceg (Broadcom)