1 / 20

Coexistence Criteria Proposal for High Rate WPAN PHY

This proposal defines and justifies coexistence criteria for the selection of an alternate high rate WPAN PHY, based on the PHY Coexistence Characterization (PCC) proposed in the 802.15.2 study group.

marianol
Télécharger la présentation

Coexistence Criteria Proposal for High Rate WPAN PHY

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [SG3a Coexistence Criteria Proposal] Date Submitted: [3July, 2002] Source: [Jeff Foerster] Company [Intel Research and Development] Company [Intel Corporation] Address [JF3-212, 2111 N.E. 25th Ave., Hillsboro, OR, 97124] Voice [503-264-6859], FAX: [503-264-3483] E-Mail:[jeffrey.r.foerster@intel.com] Re:[In response to comments taken on the selection criteria for an alternate high rate WPAN PHY.] Abstract: [This contribution proposes a definition and justification for a coexistence criteria that should be considered for the selection criteria for an alternate high rate WPAN PHY.] Purpose: [The purpose of this contribution is to more carefully define the coexistence criteria that the 802.15.SG3a proposals should be measured against. This criteria is based upon a PHY Coexistence Characterization (PCC) that was proposed in the 802.15.2 study group. Minimum criteria is also proposed for acceptance by the study group to influence future PHY proposals.] Notice: This document has been prepared to assist the IEEE P802.15. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release: The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P802.15. Intel Research and Development

  2. Coexistence Criteria Proposal Jeff Foerster Intel Research and Development Intel Corporation Intel Research and Development

  3. Overview of Talk • Why address coexistence now? • Coexistence definition • PHY Coexistence Characterization (PCC) • Justification of ‘fair and reasonable’ parameters • Proposed minimum and desired requirements • Other considerations • Conclusions Intel Research and Development

  4. Why address coexistence now? • Traditionally handled after the standard is developed • Limits coexistence mechanisms/tools • Numerous standards being developed that will share the same spectrum • Importance increases as more devices are deployed and standards developed • Need to pass sponsor/letter ballot with support from other 802 groups • Demonstrates a responsible industry • Government is giving the industry a chance to prove it can self-regulate itself in the unlicensed spectrum bands • Especially true for UWB Intel Research and Development

  5. Coexistence Definition • Characteristics of definition • Should be quantifiable • Should be relatively simple to evaluate • Should be representative of actual deployment scenario • Should be fair for both transmitting and receiving devices • Current IEEE work on coexistence • 802.15.2: Draft Recommended Practices for 802.15.1 and 802.11b (2.4 GHz) • Collaborative (2 MAC + 1 PHY using Notch filter) and non-collaborative methods specific to the PHYs (packet selection, adaptive hopping) • Presentation in May, 2002 by Ember to use PHY Coexistence Characterization (PCC) • Associated with 802.15.4 (2.4 GHz coexistence) Intel Research and Development

  6. Coexistence Definition • Possible approaches to definition • PHY BER or PER • PHY throughput • MAC throughput • MAC packet delays/collisions • PHY Coexistence Characterization (PCC) • Easily quantifiable and related to MAC throughput impact • May be pessimistic and does not include: MAC packet recovery algorithms, < 100% duty cycle for both systems • MAC throughput highly dependent on traffic assumptions and difficult to simulate Intel Research and Development

  7. Coexistence Definition • Proposed Model (based on 802.15.2 presentation on PCC by Robert Poor) • Reference Rx Nominal power is specified while dref is only informative Intel Research and Development

  8. Coexistence Definition • Critical parameters • Path loss model based on 802.15.2 (free space up to 8m and 3.3 path loss exponent > 8 m) • Reference Rx performance criteria (BER < 10e-5 or PER < 0.08) • Reference Rx nominal power • Proposed as 6 dB above standard Rx sensitivity • Same as 802.11b adjacent channel rejection spec. • Most systems will have a fade/interference margin > 6 dB • 3 dB above Rx sensitivity level used in 802.11a adjacent channel rejection spec. • Want to ensure Rx nominal power reflects reasonable operation of reference system (dref) • This is a key parameter that needs to be agreed upon by the 802.15.3a standards group for coexistence criteria Intel Research and Development

  9. Coexistence Definition • Critical parameters • Interference distance at which reference Rx performance criteria is met • This will be provided by proposers and will be PHY dependent • Selection criteria should contain the minimal acceptable dint • Proposed final definition (single parameter): • dint: The minimum distance between the 802.15.SG3a Tx and reference Rx such that the reference Rx can maintain a BER < 10e-5 when operating at 6 dB above nominal Rx sensitivity level and both devices are actively transmitting and receiving. • Initial list of reference devices: Bluetooth (802.15.1), 802.15.3, 802.11b, and 802.11a Intel Research and Development

  10. Center frequency 2.4 GHz Baud rate 1 MHz Modulation GFSK Tx Power 0 dBm Rx Antenna Gain 0 dBi Rx Sensitivity -70 dBm Interference Margin 6 dB Nominal Rx Power -64 dBm Range at Nom. Rx Power (dref) 12 m Coexistence Definition • Impact of 6 dB above standard Rx sensitivity level (sanity check) • Bluetooth • Bluetooth target applications are WPAN (~10 m) • Designed to be interference limited due to expected congestion in 2.4 GHz band Intel Research and Development

  11. Center frequency 2.4 GHz Baud rate 11 MHz Modulation DQPSK Tx Power 0 dBm Rx Antenna Gain 0 dBi Rx Sensitivity -75 dBm Interference Margin 6 dB Nominal Rx Power -69 dBm Range at Nom. Rx Power (dref) 17 m Coexistence Definition • Impact of 6 dB above standard Rx sensitivity level (sanity check) • 802.15.3 • 802.15.3 target applications are WPAN (~10 m) • Can scale down to 11 Mbps with improved sensitivity Intel Research and Development

  12. Center frequency 2.4 GHz Baud rate 11 MHz Modulation CCK (11 Mbps) Tx Power 20 dBm Rx Antenna Gain 0 dBi Rx Sensitivity -76 dBm Interference Margin 6 dB Nominal Rx Power -70 dBm Range at Nom. Rx Power (dref) 74 m Coexistence Definition • Impact of 6 dB above standard Rx sensitivity level (sanity check) • 802.11b • WLAN applications for office will most likely be ACI and CCI limited • Smaller cell sizes needed for greater density in office locations • Home applications may need more protection to cover a home • Can scale down data rate for longer range Intel Research and Development

  13. Center frequency 5.3 GHz Baud rate 11 MHz Modulation Number of carriers Carrier spacing 16-QAM Coded-OFDM (24 Mbps mode) 52 312.5 KHz Tx Power 15 dBm Rx Antenna Gain 0 dBi Rx Sensitivity -74 dBm Interference Margin 6 dB Nominal Rx Power -68 dBm Range at Nom. Rx Power (dref) 28 m Coexistence Definition • WLAN applications for office will most likely be ACI and CCI limited • Smaller cell sizes needed for greater density in office locations (~22 m) • Home applications may need more protection to cover a home (no ACI or CCI) • Can scale down data rate for longer range • Impact of 6 dB above standard Rx sensitivity level (sanity check) • 802.11a Intel Research and Development

  14. Coexistence Definition • Is 6 dB above Rx sensitivity level ‘fair and reasonable’? • For some applications, yes. • For others, no. • When is a system not otherwise interference limited? • Home environment with limited number of simultaneously operating devices (CCI and ACI less likely in many cases) • PC designs starting to reduce emissions in targeted RF bands • What about Rx antenna gain? • 0 dBi assumed, but can typically get 3-6 dBi • What about efficient Rx designs that perform better than Rx sensitivity levels? • Future chips will be able to perform much better than published Rx sensitivity levels Intel Research and Development

  15. Minimum criteria • What are reasonable values for dint? • WPAN and WLAN devices will inevitably share the same space • See numerous application presentations for the home and office • 802.11b and HomeRF currently serving the home market • 802.11a/g will be serving in near future with 802.11e QoS • WNG/HTSG work getting started to improve 802.11a to better meet home requirements • New bands may be opening up between 5.35-5.725 GHz • Combined WPAN and WLAN solutions offer significant potential for future applications • Fully integrated WPAN/WLAN solution not considered here (allows for possible coordination), but flexibility of solution will help enable • dint < 1 m and dint < 0.3 m have already been proposed and discussed in the requirements and selection criteria Intel Research and Development

  16. Minimum criteria • Proposed Criteria • Minimum criteria (1): Under normal operating conditions, the proposed PHY must be able to provide a minimum level of coexistence such that dint < 1 meter with a 6 dB interference margin for the reference receiver. • Minimum criteria (2): The proposed PHY must be able to provide an enhanced level of coexistence such that dint < 0.3 meter with a 6 dB interference margin for the reference receiver (corresponding to 10 dB more protection than (1)). This means that, if an individual implementation wants to achieve this level of coexistence, it must be able to do so and still be able to communicate with a standard 802.15.3a receiver. • DFS is an example of this kind of enhanced protection for 802.11a (being developed in 802.11h) Intel Research and Development

  17. Desired criteria • Proposed Criteria • Desired criteria: The proposed PHY should be able to provide an enhanced level of coexistence such that dint < 0.3 meter with a 0 dB interference margin for the reference receiver. This means that, if an individual implementation wants to achieve this level of coexistence, it must be able to do so and still be able to communicate with a standard 802.15.3a receiver. • Some vendors may wish to have the ability to provide even greater protection to other systems Intel Research and Development

  18. Other Considerations • PHY proposals should use ‘Good Neighbor’ policies • Adaptive power control (do not transmit more power than needed) • Time division multiplexing (do not transmit for more time than needed) • Dynamic Frequency Selection (avoid interference if possible) • Adaptive notch filtering • Selectable frequency mask (for UWB?) • Implications on MAC to maintain connectivity? Intel Research and Development

  19. Other Considerations • Practical concerns • How should proposals address coexistence? • The more information the better • Combination of analysis, semi-analytical monte-carlo simulations, or full simulations could be used • Provide filter masks that show emitted power in the bands of interest • Only a first level approximation, and useful only for WGN-like interference • Need justification of WGN approximation, if used, compared to pulsed or CW-like interference (specifically for UWB) • Actual testing results if available • In the end, the task group will be responsible for ensuring coexistence of final solution (not just proposers) Intel Research and Development

  20. Conclusions • Adopt the PHY Coexistence Criteria (PCC) to measure coexistence • Single parameter needed (dint) • Adopt minimum and desired criteria which I believe is fair and reasonable for all concerned • Minimum level of coexistence for all PHYs • Minimum level of flexibility for enhanced coexistence • Desired level of flexibility for enhanced coexistence • Could add other reference systems to coexistence list (cellular, cordless phones) • Coexistence should not be taken lightly • Especially for UWB devices • Consumers will benefit in the end Intel Research and Development

More Related