Electromagnetic Compatibility and Radio Spectrum Matters

The present document is the second part of the Smart Metering Wireless Access Protocol describing the data structures and functional operation of Smart Metering and other applications intending to use spectrum resources covered by TS 102 887-1 [1] Physical Layer. TS 102 887-1 [1] is derived from IEEE 802.15.4g-2012™ [5] and the present document is derived from IEEE 802 15.4-2011™ [3], IEEE 802.15.4e-2012™ [4] and ANSI/TIA-4957-200 [2] together with specific enhancements or adaptations for the European context.

The present document, together with its associated PHY Technical Specification [1], provide radio communications connectivity for continuously powered or battery operated Smart Metering devices which, when coupled with suitable transport protocols, support advanced metering and other energy related applications. The MAC/PHY combination is also suitable for a wide range of sensor and Machine-to-Machine applications characterised by low device duty cycle and operation in shared spectrum.
This wide range of applications requires efficient connectivity protocol support for intermittent bi-directional data exchanges between devices in both low density (e.g. rural) and high density (e.g. urban) environments covering operations as simple as discovery and connection between one pair of devices (e.g. for walk-by meter reading) up to networks of many devices sharing a Network Point of Attachment to an external wide area network.
Spectrum sharing imposes additional requirements on the lower layer communications protocols governed by regulations limiting power and duty cycle among other characteristics. Such regulations taken into account by the present document include those governing the operation of Short Range Devices. Simple and low density deployments may be supported by distributed or cluster-based control algorithms, e.g. as found in [3] and [4], operating on a single channel. Frequency agility to select or change operating channel to minimise interference is advantageous for these applications but not essential for their operation.
Dense deployments and more complex applications may be constrained by spectrum sharing rules designed to limit the interference to other devices or services from the data traffic generated. In these cases the optimum control algorithms spread the population of devices uniformly over the available spectrum (channels) to minimise the number of devices on any given channel thereby minimising interference from their generated traffic. Device behaviour defined in [2] automatically distributes devices over the available channels by using device-centric pseudo-random channel hopping but also supports single channel operation via a degenerate hopping algorithm always returning the same channel number.
Both approaches to systems design may be deployed using the same PHY protocol and in the same frequency range and it is therefore necessary to include facilities to discriminate between information belonging to each MAC approach. Nothing prevents an implementation choosing to use only one of the alternate approaches or supporting both and the present document provides the necessary data structure encoding to identify each unit of information in its correct context.

The present document provides adaptations to IEEE Std 802.15.4g-2012 [2] in order to comply with the European regulations for Short Range Devices (SRDs).

The requirement to wirelessly interconnect Smart Meters is one of the responses to the EC's mandate 441 [i.1] for an open architecture for utility meters. Short Range Device (SRD) technology has been identified as a candidate technology to interconnect meters to the Wide Area Network (WAN) Access Point (AP).
The present document is derived from IEEE Std 802.15.4g-2012 [2] (Amendment to IEEE Std 802.15.4-2011 [1]).
The modifications include a restriction of the base document for use in the frequency band 870 to 876 MHz and 915 to 921 MHz.

The requirement to wirelessly interconnect Smart Meters is one of the responses to the EC's mandate 441 [i.1] for an open architecture for utility meters. Short Range Device (SRD) technology has been identified as a candidate technology to interconnect meters to the Wide Area Network (WAN) Access Point (AP).
The present document is derived from IEEE Std 802.15.4g-2012 [2] (Amendment to IEEE Std 802.15.4-2011 [1]).
The modifications include a restriction of the base document for use in the frequency band 870 to 876 MHz and 915 to 921 MHz.

This work item revises the System Reference document (SRdoc) ETSI TR 103 149 v.1.1.1 with updated information on DECT and DECT ULE. Further, the revision will inform about the running activities at ETSI towards DECT evolution and DECT-2020 targeting to serve new application domains like Wireless Automation, Industry 4.0 and Creative and Culture Industry including PMSE.

The present document applies to a new class of SRD devices specifically for Smart City applications operating in the UHF frequency band from 870 MHz to 876 MHz. It extends the discussion from Smart Metering Requirements discussed in TR 102 886 [i.1] and TR 102 649-2 [i.7] to a wider set of applications that are presented. Particular performance and compatibility parameters needed for the successful operation of SRD devices used in smart cities application are also identified.

Short Range Device (SRD) technology is technology of growing use to interconnect sensors, actuators and remote control and monitoring systems. With time, technological progress and higher awareness of environment related questions will promote widespread use of sensor networks able to gather data at the scale of a city.
Consequently, SRD technology will be used to interconnect all of those sensors, actuators and infrastructures.
The present document examines whether the performance requirements, access mechanism and transmitted power currently in use for SRDs are adequate for Metropolitan Mesh Machine Network (M3N) and opens a discussion on further work required to establish the magnitude of any compatibility issues in sharing the 870 MHz to 876 MHz frequency band.
The present document identifies a relevant set of M3N applications that will transmit data over the M3N network. This permits to model a typical M3N deployment in term of number of devices, infrastructures and density. The same applications set also identify the key service requirements which will impact the volume of traffic to be transmitted between endpoints and network infrastructure. A structured mesh network is assumed as it accommodates the limited power available for data transmission and minimises the number of gateways. The mesh traffic is modelled and the expected network performance established. This is then compared with the current SRD regulatory limits.
The present document then discusses required changes in SRD rules to enable reliable and economically viable M3N operations. The discussion on compatibility assumes that the military services will be displaced by E-GSM-R and that it is with this service that the SRDs will share the frequency band. Intersystem interferences have already been addressed in TR 102 649-2 [i.7] and TR 102 886 [i.1], and is not repeated here.

The present document applies to a new class of SRD devices specifically for Smart Metering applications operating in the UHF frequency band from 870 MHz to 876 MHz. It extends the discussion on Smart Metering Performance Requirements in TR 102 649-2 [i.22] and identifies the particular RF performance parameters needed for the operation of these devices.

The requirement to wirelessly interconnect Smart Meters is one of the responses to the EC's mandate 441 [i.1] for an open architecture for utility meters. Short Range Device (SRD) technology, has been identified as a candidate technology to interconnect meters to the Wide Area Network (WAN) Access Point (AP).
• The TR 102 649-2 [i.22] identified.
• Preliminary performance requirements for SRDs for use with Smart Meters.
• An uncoordinated time bound access mechanism, with 25 mW. e.r.p. power.
A suggested frequency designation of 873 MHz to 876 MHz which is one of the sub-bands of the 870 MHz to 876 MHz and 915 MHz to 921 MHz duplex pair currently allocated for E-GSM-R and military use.
The present document examines whether the performance requirements, access mechanism and transmitted power currently in use for SRDs are adequate for Smart Meters and opens a discussion on further work required to establish the magnitude of any compatibility issues in sharing the 873 MHz to 876 MHz frequency band.
The present document identifies the key service requirements which will impact the volume of traffic to be transmitted between meter and AP. A mesh network is assumed for the delivery of data between meter and AP as this accommodates the limited power available for data transmission and minimises the number of APs. The mesh traffic is modelled and the expected network performance established. This is then compared with the current SRD regulatory limits.
The discussion on compatibility assumes that the military services will be displaced by E-GSM-R and that it is with this service that the SRDs will share the frequency band. The report examines the potential for co-channel inter-system interference using as a starting point the work undertaken at the BNetzA laboratory at Kolberg in August 2009 [i.25]. Adjacent channel interference has already been considered in TR 102 649-2 [i.22] and is not repeated here. Intra-system interference from collocated SRD systems is being addressed in CEPT SE 24 under WI23 and although the results of these deliberations are not yet available draft information is available on the CEPT web site. Further work on low duty cycle as a mitigation technique for SRDs has been approved by ETSI and the Special Task Force (STF) 411 expects to complete its work within 9 months. A measurement campaign on Low Duty Cycle requirements was recently completed by the JRC [i.33] and the reader is invited to consider the preliminary results of this work when reviewing clause B.3 on Access mechanisms. These activities will guide the development of future analyses in the present document.