EUROPEAN COMMISSION Communications Networks Content & Technology Directorate-General Electronic Communications Networks & Services Spectrum Brussels, 18 March 2015 DG CONNECT/B4 RSCOM15-19 PUBLIC DOCUMENT RADIO SPECTRUM COMMITTEE Working Document Subject: Letter from ECC: views on DA2GC for railways This is a Committee working document which does not necessarily reflect the official position of the Commission. No inferences should be drawn from this document as to the precise form or content of future measures to be submitted by the Commission. The Commission accepts no responsibility or liability whatsoever with regard to any information or data referred to in this document European Commission, DG Communications Networks Content & Technology, 200 Rue de la Loi, B-1049 Bruxelles RSC Secretariat, Avenue de Beaulieu 33, B-1160 Brussels - Belgium - Office BU33 7/09 Telephone: direct line (+32-2)299.66.11 / 295.26.65 switchboard (+32-2)299.11.11. Fax: (+32-2) 296.83.95 E-mail : cnect-rsc@ec.europa.eu
CEPT ECC Electronic Communications Committee To Mr Andreas Geiss European Commission DG CONNECT BU-33 07/55 Avenue de Beaulieu/Beaulieu laan 33 1160 BRUSSELS Belgium Date 6 th March 2015 Our reference L15-ECC-004 Enclosures ECC Views Broadband for trains Your reference Subject Broadband DA2GC network / spectrum for providing broadband services to passengers in trains Dear Mr Geiss, ECC, at its 39 th meeting from 3-6 March 2015, discussed the possible usage of broadband DA2GC network / spectrum for providing broadband services to passengers in trains ( In-Train- Entertainment/RLAN ), because this was addressed during the 50 th Radio Spectrum Committee meeting on 9 December 2014. The ECC views on this matter, which is outside the scope of the Mandate on the unpaired 2 GHz bands, are kindly provided in the attached document. Best regards, Eric Fournier Chairman CEPT Electronic Communications Committee Eric Fournier ECC Chairman ANFR 78 Avenue du général de Gaulle F- 94704 Maisons Alfort - France E-mail Telephone Telefax Eric.fournier@anfr.fr +33145187348 +33145187313
Attachment to letter L15-ECC-004 ECC views on possible usage of broadband DA2GC network / spectrum for providing broadband services to passengers in trains ( In-Train-Entertainment/RLAN ) 1 Aspects and considerations The following aspects and considerations are based on a possible Broadband DA2GC solution in the band 1900-1920 MHz, although most of these arguments would also be relevant for a Broadband DA2GC solution in the band 5855-5875 MHz, this band is not addressed in the EC Mandate and therefore not directly relevant for the response to the Commission. 1.1 Coverage of a DA2GC network vs. a rail network A DA2GC network should cover the airspace between 3 000 m and 10 000 m above ground. Therefore an up-tilt of the ground station antennas is required. For normal terrestrial mobile network base stations antennas with a down-tilt are required to reach the appropriate coverage. For providing services to trains, coverage of the railway tracks and the railway stations is required. 1.2 Structure of a DA2GC network vs a rail network In the frequency band 1900-1920 MHz the distance between the base stations for a rail network would be rather short (about 5-8 km depending on the antenna gain used at the base station). The inter-site-distance for a DA2GC network in this frequency band would be about 100 km. Also the number of base stations (ground stations) would be completely different. For example, for Germany (with an area of about 360 000 km 2 ) less than 20 ground stations would be sufficient for a DA2GC network in the band 1900-1920 MHz. For a dedicated terrestrial network covering more than 30 000 km railway tracks a considerable number of additional base stations would be necessary. For comparison, it should be noted that about 3000 base stations are in operation in Germany for GSM-R in the 900 MHz range. The roll-out of such a high number of base stations would completely change the economic considerations made for DA2GC (business case etc.). This would still be the case if only the railway tracks for the high speed trains would be covered. 1.3 Capacity of the networks The density of trains and consequently the density of users in the trains at railway stations would have to be considered. Resources for such a high demand in specific areas could not be provided additionally by a DA2GC network. Also the coverage of tunnels would not be possible. 1.4 Sharing of spectrum between a DA2GC network and a railway network The considerations as described above are based on the assumption that the same network (the Broadband DA2GC network) would also be considered for providing broadband services to trains. Another theoretical option, in principle, would be to consider a separate terrestrial network in the same band, then the sharing possibilities between this network and the Broadband DA2GC network needs to be investigated. Studies already carried out in FM48 and SE44 between Broadband DA2GC and other radio applications in the frequency band 1900 1920 MHz and adjacent to it have shown that DA2GC is highly unlikely to be able to share with another densely outdoor deployed network
such as the one to provide access to In-Train RLAN. The studies so far have concluded that for co-frequent operation with unlicensed applications; an indoor restriction is needed as well as further spectrum access restrictions (i.e. transmitter power and duty cycle restrictions). In addition, the necessity to protect the UMTS above 1920 MHz resulted in severe downlink restrictions to be imposed on any ground-based stations. This would make the deployment of a system to provide connections to trains difficult and expensive. 2 Conclusions based on the aspects / considerations as described above The following conclusions are based on the considerations as described above, because detailed technical studies have not been carried out so far with regard to the idea of providing broadband services to trains by using the band 1900-1920 MHz. The EC Mandate to the CEPT regarding the Unpaired 2 GHz bands does not encompass this idea. The differences between a Broadband DA2GC network and a network for providing broadband services to trains are significant. Therefore one single network could not be used for both purposes. Also sharing between two different networks (in the same band, one for DA2GC and one for the railways) seems highly unlikely to be feasible. Currently RLAN in trains are in most cases connected to the public broadband networks by using mobile cellular frequencies and networks (see Annex). It would most likely not be economical to roll out special networks with the sole purpose to connect trains to broadband services. Regarding spectrum availability and economy it is hard to justify deploying special networks to feed In-Train-RLAN. Standardized cellular mobile equipment on European (or globally) harmonised frequency bands are much less expensive due to economy of scale compared to using non-cellular spectrum. Thus operators and railway companies should in any case focus their activities on standardized LTE/LTE-A-solutions with an established or at least developing global eco-system. 3 General оptions to connect In-train-RLAN to the public broadband network The following options can be distinguished to backhaul In-Train-RLAN: a.) Use the existing mobile cellular infrastructure Currently 800 MHz LTE spectrum enables a mobile network operator to cover railway tracks in rural areas. In future LTE700 and LTE900 will become available for that purpose. In urban areas UMTS as well as LTE800/1800/2600 can be used. Possibility to introduce prioritization of railway traffic to improve availability. Enhancement by employing carrier aggregation within one network (see the German example described in the Annex). Possibility to employ carrier aggregation by multi-network operation (multiple SIM). b.) Provide additional capacity for railway tracks in the cellular network Enhanced network planning and additional deployment/investment to especially improve coverage and capacity for railways. Add urban spectrum (currently 1800 and 2600 MHz base stations) with directional antennas at the base stations to provide additional coverage and capacity for railway tracks in rural areas. c.) Provide additional capacity by using non-cellular spectrum and equipment 2
Carrier aggregation by deployment of additional capacity in other frequency ranges on a secondary basis in agreement with an incumbent operator (e.g. military or governmental agency); LSA (Licensed Shared Access) approach. This may result in non-standardised equipment due to the use of non-cellular spectrum. Non-standardized equipment in general reduced the economy of the system considerably. Annex An example: Broadband access in trains in Germany Currently the issue of passenger internet access in trains and public transport is increasingly discussed. Two radio systems are described being in operation in Germany to either improve mobile broadband communication directly via cellular spectrum by using In-Train-Repeaters or by In- Train-RLAN (mobile hotspots) which are being connected (backhauled) to the public broadband network by using cellular mobile networks. 1. In-Train Repeaters Since 2007 all the German mobile network operators have been cooperating with Deutsche Bahn (DB) to improve access of passengers to their mobile networks by installing In-Trainrepeaters in some 250 ICE (high speed trains). These repeaters are high quality broadband amplifiers to enhance mobile cellular voice and data-connectivity for GSM in the passenger cabin for the GSM-R-, 900MHz- as well as the 1800 MHz-range. Currently a replacement of these GSM-repeaters is planned to provide broadband coverage in ICE trains. These new multi-technology repeaters will therefore support frequency bands 800/900/1800/2100/2600 MHz (for GSM/UMTS/LTE), with one additional/optional band (probably 700 MHz) to be included later. Due to the mutually agreed concept and high bandwidth these repeaters considerably improve the availability for all cellular mobile networks in high speed trains of DB. 2. Connection of In-Train-RLAN to the public broadband network Another convenient way for passengers to access the internet is by using In-Train-RLAN. Deutsche Telekom is operating mobile hotspots in 250 ICE trains of DB serving RLANs in the passenger compartments. The backbone for these RLANs is provided by parallel operation of two cellular mobile radio modems each capable of using the bands 900/2100 MHz for UMTS and 800/1800/2100/2600 MHz for LTE. Two carriers can be aggregated to increase backhaul capacity for the RLANs. The operation of these systems is a matter of commercial agreements by the railway operator and the respective mobile network operators. 3