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IEEE 802.15.4g Comments In Support of Harmonized Dedicated Band Usage

IEEE 802.15.4g Comments In Support of Harmonized Dedicated Band Usage. PURPOSE (from IEEE 15-00-0439-01-004g May 09; Emphasis added)

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IEEE 802.15.4g Comments In Support of Harmonized Dedicated Band Usage

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  1. IEEE 802.15.4g Comments In Support of Harmonized Dedicated Band Usage PURPOSE (from IEEE 15-00-0439-01-004g May 09; Emphasis added) To provide a global standard that facilitates very large scale process control applications such as the utility smart-grid network. This amendment supports large, geographically diverse networks with minimal infrastructure. Smart Metering Utility Networks can potentially contain millions of fixed endpoints. The communication range, robustness, and coexistence characteristics required for this class of application have not been met with existing 802 standards (See explanatory notes in Section 8.1 Doc#15-08-705). The FCC provides Licensed Spectrum to increase range and robustness of operation. FCC licensed operation for decades are proven to serve geographically diverse regions. The FCC regulates Licensed channels so that they are insured of coexistence. Licensed channels, due to higher power levels and higher allowed antenna gains, insure minimum infrastructure. Global operation requires flexibility of spectrum classification. Many countries do not provide licensed exempt spectrum (outside of 2.4 GHz) or use other methods for spectrum allocation. <Britton Sanderford>, <Sensus>

  2. IEEE 802.15.4g Comments In Support of Harmonized Dedicated Band Usage (cont.) When there are coexistence questions, Licensed Band option can provide risk mitigation. Otherwise, Global operation is dependent largely on 2.4 GHz (note the “PURPOSE” says “the 802 standards have not succeeded” which largely operate at 2.4 GHz.) 2.4 GHz limitations to consider: • ATTENUATION - from water absorption (for example, European style buildings 1-2 foot thick 200 year old brick and mortar);  • FADING - since the 2450 wavelength is 2.67 x shorter than a 915 wavelength; this will cause 7.1 x antenna positions that cause deep fades per unit area; • DOPPLER – Causing Dynamic Fading; 915 has Less fades per unit time;  Will likely require antenna diversity, as is the case in present 802.11 2.4 GHz networks • PATH LOSS - 2450 has 4.6 db greater path loss through suburban vegetation than 915 MHz; • COEXISTENCE -  Will an AMI/ Smart Grid system impact 802.11 or 802.15 which operate in the same 2.4 GHz bands; Examples need to be studied.

  3. IEEE 802.15.4g Comments In Support of Harmonized Dedicated Band Usage (cont.) • PAR(from IEEE 15-00-0439-01-004g May 09; Emphasis added) • This Standard defines an amendment to IEEE 802.15.4. It addresses principally outdoor Low Data Rate Wireless Smart Metering Utility Network requirements. It defines an alternate PHY and only those MAC modifications needed to support its implementation. • Specifically, the amendment supports all of the following: • Operation in any of the regionally available license exempt frequency bands, such as 700 MHz to 1 GHz, and the 2.4 GHz band. *It was determined in past 802.15.4g meetings that the PAR was not intended to be exclusionary, “supports” does not mean “limited to” • *IEEE 802.16 is not limited to “Licensed Exempt.” There is likewise no technical requirement for this restriction in 802.15.4g • *If exclusionary, the term “License Exempt” is not defined by the FCC or globally and could limit access to international spectrum • *If exclusionary, the term “License Exempt” could limit utilities’ access to approximately 22 MHz of Licensed spectrum. • *If exclusionary, this could block utilities from access to spectrum the FCC is currently considering Licensing for Smart Grid applications. • *Market consideration: Many utilities want the option of Licensed Band operation. • *Ironically, a “Licensed Exempt” collector will likely use a licensed band WAN backhaul. <Britton Sanderford>, <Sensus>

  4. IEEE 802.15.4g Comments In Support of Harmonized Dedicated Band Usage (cont.) • Data rate of at least 40 kbits per second but not more than 1000 kbits per second Prior 802.15.4g meetings determined that lower data rates would meet the PAR • Lower data rates will increase link margin and can eliminate repeaters to: below grade meters, meter vaults, high-rise apartments, rural applications, underground FCI, etc. • Licensed bands may also achieve > 40 kb/s data rates by use of parallel channels, while maintaining full sensitivity to enable reach. • Achieve the optimal energy efficient link margin given the environmental conditions encountered in Smart Metering deployments. • Licensed operation supports this goal with FCC regulations that insure lower noise and adjacent channel interference • Principally outdoor communications • Licensed band operation supports both indoor and outdoor endpoints • PHY frame sizes up to a minimum of 1500 octets • Licensed band can support a wide variety of payload lengths <Britton Sanderford>, <Sensus>

  5. IEEE 802.15.4g Comments In Support of Harmonized Dedicated Band Usage (cont.) • Simultaneous operation for at least 3 co-located orthogonal networks • Licensed Spectrum inherently accomplishes this purpose. • Connectivity to at least one thousand direct neighbors characteristic of dense urban deployment. • Licensed Band devices may use parallel channels to connect to >> 1000 neighbors • Provides mechanisms that enable coexistence with other systems in the same band(s) including IEEE 802.11, 802.15 and 802.16 systems • Licensed Band devices by their nature insure coexistence and provide options which reduce risk. Consider impact on (IEEE 802.11, 802.15) 2.4 GHz operation, example: • ((1500 octets * 8)/ 50 kb/s) * 1000 Direct Connect Neighbors in PAR = 240 seconds • Assume 2x on-air time to allow for Poll/IP/Security/Protocol • A 15 minute update rate would yield 80% on-air time • Other contributors to study: • Dwell time per hop, number of hops, antenna height, • “noise” reach is greater than “Connect” reach, etc <Britton Sanderford>, <Sensus>

  6. IEEE 802.15.4g Comments In Support of Harmonized Dedicated Band Usage (cont.) Practical Considerations *Increasing spectrum options will increase the volume of ICs with common attributes. *The Smart Grid market that SUN serves is based on utility RFQs. No two are the same. There are IOUs big and small, combo utilities, municipal, Co-ops, even government facilities. Each has a different business case and geography with a diversity of applications. *Utility DefinedModes should be an option to Mandatory Modes. This will allow a utility to have the option of Battery Operation and flexibility to connect Hard-To-Reach endpoints. <Britton Sanderford>, <Sensus>

  7. Licensed Band meets the technical objectives of the PAR in every respect. • Licensed Band operation supports the objectives of the “PURPOSE”. • Licensed Band supports the interests of the Smart Grid market users. • Licensed Bands are available on an even basis to Vendors and Utilities Worldwide. • Governments are in the process of providing Licensed Spectrum to Utilities. • Licensed Band operation submitted prior to 7/12/09 meeting in San Francisco. <Britton Sanderford>, <Sensus>

  8. Overview of Bands P802.15-09-0627-03-004g CPP Band Table 1 Band Table 2 <Britton Sanderford>, <Sensus>

  9. Table 1a Complete Informative Tab in Comments <Britton Sanderford>, <Sensus>

  10. Multi-band Harmonization Proposal (64 bit ‘signature’) Channel Separation 1 2 3 4 5 6 N Base Frequency Channel Number • Base Frequency of Frequency Band Used by Utility • 10 Hz resolution, 30 Bits provides a 10 GHz range • Channel Separation • 250 Hz resolution, 11 Bits provides up to 512 kHz steps • Channel Number • 11 Bits allows multi-band operation; for example @50 kHz CS = 3.2 GHz • Number of Hops (possibly in MAC) • 1-N, 8 Bits provides 256 Hops • For example @ 200 kHz Channel Separation = 51.2 MHz • Modulation • 2 FSK/GFSK (H=1.0), 2 GFSK (H=0.5), Optional: 4 GFSK (H=0.33), OFDM; 4 Bits • Data Rate, kb/s • [5, 10, 20, 40; 2 GFSK H=0.50], [50, 100, 150, 200; 2FSK/GFSK H=1.0] • Set by Channel Separation & Modulation <Britton Sanderford>, <Sensus>

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