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Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: Recommendation on Data Rates for SUN Date Submitted: March 15, 2010 Source: Chris Calvert, Dave Olson, Emmanuel Monnerie, Ruben Salazar, Nick West, Harry Sarkas Company Landis+Gyr
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Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title:Recommendation on Data Rates for SUN Date Submitted: March 15, 2010 Source: Chris Calvert, Dave Olson, Emmanuel Monnerie, Ruben Salazar, Nick West, Harry Sarkas CompanyLandis+Gyr Address 30000 Mill Creek Avenue, Alpharetta, GA USA Voice: 678- 258-1500, E-Mail: firstname.lastname@LandisGyr.com Re: Comment Resolution for document # 5-10-0014-00-004g-clause-6-fsk-phy-draft Abstract: Recommendation to use data rates related to existing standards Purpose: Clarification on comment #344 (reference document: 15-10-0031-10-004g) 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. Landis+Gyr
The communicating meter Communication Unit NAN Metering Unit LAN (Optical Port) Landis+Gyr
Existing Standards Currently being amended by this Task Group IEEE 802 Communication Unit NAN ANSI C12.21 ANSI C12.18 Metering Unit LAN (Optical Port) Source : NIST Framework and Roadmap for Smart Grid Interoperability Standards Landis+Gyr
ANSI C12.18 • Defines the meter’s optical port interface used for diagnostics, testing, manufacturing and maintenance. • Data rates based on EIA RS-232 standard • Specifies the following data rates: 300, 600, 1200, 2400, 4800, 9600, 14400, 19200, 28800,57600 bps • Required in most meters (>90% of RFQ’s in the USA) • Implemented by all meter vendors and meter communication module manufacturers Landis+Gyr
ANSI C12.21 • Defines the meter communication standard via telephone modems, typically using ITU standard speeds: 9600bps (V.32), 12000 (V.33), 14400 (V.33), 28800 (V.34), 33600bps (V.34), 48000bps (V.92), 56000bps (V.90/V.92) • Used to be the only Standard WAN for the meter (mostly in commercial and industrial meters). • The interface between the meter and the communication module has always been based on EIA RS-232 standards. Landis+Gyr
RS-232 data rates in SUN • 10’s of millions of ANSI-compliant communicating meters deployed since the 90’s in the USA. • The vast majority already support RS-232 data rates and is also using these rates for the NAN. • The most popular data rates for NAN already deployed are 2400bps and 9600bps. • The most popular data rates for SCADA devices already deployed are 4800bps, 9600bps and 19200bps. Landis+Gyr
RS-232 data rates are easier to implement The value represents the minimum multiplier that must be applied to the crystal frequency to be able to achieve the corresponding data rate. Landis+Gyr
Consequences of the wrong choice • Clocks and other hardware that are optimized for existing standards might not support the mandatory mode. • It would prevent millions of devices from becoming compliant with SUN standard. • Everybody will be penalized: our customers and the consumers… Landis+Gyr
Spirit of the NIST Framework “Architectures should be flexible enough to incorporate evolving technologies. They also must support interfacing with legacy applications and devices in a standard way, avoiding as much additional capital investment and/or customization as possible.” Source : NIST Framework and Roadmap for Smart Grid Interoperability Standards Landis+Gyr
Regional Applicability • Countries that are using ANSI standards in the meter may prefer to implement RS-232 data rates. • Japanese band may require a data rate of 50kbps due to local constraints. Landis+Gyr
Recommendation • Use a data rate that is related to EIA RS-232 standard. • The closest values to current proposal are 38.4kbps or 57.6kbps. These two choices will allow a better adjustment to local regulations (side-lobe emissions). • devices built around these data rates can usually be used at 51.2kbps, which is even closer to the current proposal (51200=38400*4/3). • This choice is the least likely to raise technical issues with existing devices. • Following this recommendation allows current devices an opportunity for migration within the spirit of the NIST Framework Landis+Gyr
Thank you! Landis+Gyr
Appendix Landis+Gyr
OFDM and RS-232 data rates Landis+Gyr