Intelligent Transport Systems

Two recently published CEPT Reports set out the spectrum parameters that will facilitate safer and more effective intelligent transport systems in the future

The development of connected and autonomous vehicles has had a further boost after the Electronic Communications Committee (ECC) approved two CEPT Reports that will facilitate their development. At its 50th meeting, which was held in Brighton in the UK from 4-8 March, the ECC approved:

• CEPT Report 70 in response to the permanent European Commission (EC) Mandate on Short Range Devices (SRDs). This Report contains a range of proposals to assist in the seventh update of the SRD Commission Decision. Amongst these is the proposal of two initiatives which are intended to help drive innovation in the automotive sector and to improve the safety of road vehicles.
• CEPT Report 71 in response to the EC Mandate to CEPT to study the extension of the Intelligent Transport Systems (ITS) safety-related band at 5.9 GHz. This Report proposes extending the upper edge of the EC harmonised safety-related ITS band (5875-5905 MHz) by 20 MHz up to 5925 MHz. In addition, it proposes to harmonise the frequency band 5925-5935 MHz for safety-related Urban Rail ITS applications.

CEPT Report 70

CEPT Report 70 makes two proposals for Transport and Traffic Telematics (TTT).

First, the Report suggests widening the frequency bandwidth in the 60 GHz range from 63-64 GHz to 63.72-65.88 GHz. This would facilitate TTT to better align with the channelisation of wideband data transmission systems operating in the 57-66 GHz range. The power limitation remains unchanged at 40 dBm e.i.r.p. This improvement is described more fully in the draft ETSI Systems Reference Document (SRDoc) on the technical characteristics of Multiple Gigabit Wireless Systems (MGWS) in radio spectrum between 57 GHz and 71 GHz (TR 103 583). This draft SRDoc notes that the current 63-64 GHz ITS allocation overlaps two of the MGWS channels, specifically Channel 3 and Channel 4.

Shifting the CEPT allocation so that it only overlaps with a single channel would significantly enhance sharing operation. The shift and the combined increase of the allocated spectrum will allow ITS applications to take advantage of existing MGWS technology. This will greatly reduce both cost and deployment time for ITS applications. ETSI is currently developing the necessary equipment standards for ITS in this revised frequency band.

Second, the Report suggests allowing smart tachograph – the new generation of on-board digital recorders – in the frequency band 5795 to 5815 MHz, as set out in the table below.

Smart tachograph, weight and dimension applications are defined as "remote enforcement of the tachograph in Appendix 14 of the Commission Implementing Regulation 2016/799 and for the weights and dimensions enforcement in Article 10d of EU Directive 2015/719".

The regulations allow for the use of an interrogator device called a Remote Early Detection Communication Reader (REDCR). There are two use cases for this technology:

• The in-vehicle unit is read out by a fixed or portable REDCR located at the roadside which is directed towards the centre of the windscreen of the passing vehicles it wants to inspect.
• The in-vehicle unit is read out from a mobile REDCR situated within a moving vehicle and directed towards the centre of the windscreen of the vehicle it wants to inspect.

This technology will allow road enforcement authorities to interrogate the tachograph unit on the commercial vehicle. There are clear benefits for safety in allowing police forces to read tachograph information without the need to pull over each vehicle of interest.

The original compatibility analysis can be found in ECC Report 291 - Compatibility studies between smart tachograph, weight and dimension applications and systems operating in the band 5795-5815 MHz and systems operating in adjacent bands.

ETSI EN 300 674 for TTT will be the applicable harmonised standard for smart tachograph, weight and dimension applications.

CEPT Report 71

CEPT Report 71 suggests significantly increasing the radio spectrum available for safety-related ITS systems. In February 2017 the Radio Spectrum Policy Group (RSPG) delivered its opinion on spectrum aspects of ITS which states that "there is no evidence that spectrum availability is currently a constraint on the development of ITS, and there is no immediate need to take regulatory action in this regard. However, given the momentum of policy and standardisation development for ITS, we recommend that the options for ITS to expand to share spectrum for safety-related ITS in the 20 MHz above the existing designation and, for non-safety-related ITS, in the 20 MHz below, should be kept available for the time being. It is also important to take into account the developments in ITS technologies and the introduction of Communication Based Train Control (CBTC) within the ITS designation".

CEPT considers that its Report satisfies the RSPG opinion of 2017 and that it can be used as a basis for the amendment of EC Decision 2008/671/EC on safety-related ITS.

Since the introduction of the current ITS regulations in Europe, new technologies have emerged that are intended to meet the demands of safety-related ITS. These include the ETSI G5 system and the LTE V2X system. There are significant differences in the way these systems are designed and in the way they are intended to facilitate intra-system sharing. Neither of these systems was designed with a view to easy interoperability with alternative systems. ETSI is, however, currently attempting to resolve this issue. It is expected that ETSI will publish two technical reports on ITS system intra-operability (TR 103 666 and TR 103 667) in late 2019.

CBTC systems are intended to improve efficiency in the running of urban rail systems, typically allowing trains to run at under 90 seconds apart. CBTC systems are a different technology to the systems being proposed for road ITS. The use case scenario is different from the road vehicle, where road vehicles are more densely co-located. CEPT Report 71 recognises the challenges of CBTC sharing with road ITS systems. It suggests that CBTC operate in the frequency band 5925-5935 MHz. It also suggests that CBTC has some priority over road ITS in the frequency band above 5915 MHz where urban rail CBTC and road ITS are co-located.

The compatibility studies underpinning the CEPT Report 71 can be found in ECC Report 290 - Studies to examine the applicability of ECC Reports 101 and 228 for various ITS technologies under EC Mandate (RSCOM 17-26Rev.3).

The ECC will continue to monitor developments in ETSI, regarding intra-operation of alternative ITS technologies. Taken together, these two CEPT Reports, in response to EC mandates, are intended to set out the spectrum parameters that will enable vehicles to operate more safely and more efficiently. Ultimately, they will facilitate the development of truly intelligent transport systems which will improve the user experience, increase safety and reduce the impact of transport on the environment.

Robin Donoghue
Frequency Management Expert
European Communications Office