The Telecom Regulatory Authority of India (TRAI) has released a consultation paper on “Spectrum Require­­me­nts of National Capital Region Transport Cor­poration (NCRTC) for Train Control System for Regional Rapid Transit Sys­tem (RRTS) Corridors”. Previously, the De­pa­rt­ment of Telecommunications (DoT) had informed TRAI that the NCRTC had reques­ted the department for allotment of spectrum for the RRTS. The RRTS is being implemented by the NCRTC in eight rail corridors including three rail corridors of an approximate length of 350 km: Delhi-Ghaziabad-Me­erut; Delhi-Guru­gr­am-Alwar and Delhi-Panipat in Phase I.

To this end, DoT requested TRAI to provide recommendations on adminis­tr­a­tive assignment of spectrum to the NCRTC, as well as the quantum, pric­ing/charging thereof, and any other terms and conditions, for separate spectrum re­qui­rements of NCRTC in the 700 MHz band.

Consequently, TRAI has released a consultation paper seeking inputs from st­a­keholders. In the consultation paper, sp­ecific issues have been raised for the con­sideration of the stakeholders. TRAI has in­vited written comments on the issues from the stakeholders by July 7, 2022, and counter-comments by July 21, 2022.

A look at the key issues discussed in the consultation paper…

Spectrum assignment to NCRTC

The NCRTC is a joint venture of the Govern­ment of India and the states of Haryana, Rajasthan, Uttar Pradesh and Delhi. NCRTC has been mandated to im­plement the RRTS in eight rail corridors, including three rail corridors of an approximate len­g­th of 350 km: Delhi-Ghaziabad-Meerut, Delhi-Gurugram-Al­war and Del­hi-Panipat in Phase I. Meanwhile, five further corridors will be taken up in Phase II and are currently at the planning stage. These are Delhi-Faridabad-Palwal, Gha­zia­bad–Khurja, Delhi-Baha­dur­ga­rh- Roh­tak, Ghaziabad-Hapur and Delhi-Sh­ah­dara-Baraut. the NCRTC has decided to deploy the European Train Control Sys­tem level-2 signalling system, mission-cri­tical voice and internet of things-based as­set monitoring services, and video surveillance on trains for captive use.

The NCRTC had requested DoT to allocate 5 MHz of spectrum in the 700 MHz or 900 MHz band for operation of mission-critical services (signalling and voice and asset monitoring) along the RRTS corridor. Since signalling in railway networks requires low bandwidth and high coverage spectrum, spectrum in sub-1 GHz bands would be suitable. To this end, TRAI, in its consultation paper, has sought stakeholders’ views regarding the spectrum that should be assigned to the NCRTC for their LTE for railways technology-based train control system for the RRTS rail corridors.

Diverse use cases

While no request for spectrum require­me­nts from other RRTS/metro rail networks have been received so far by DoT, the possibility of such demands in the future in other states cannot be ruled out. Assign­me­nt of the same spectrum to different RRTS/metro rail networks could occur in two different scenarios – one where two RRTS/metro rail networks are geographically separated, and another where more th­an one rail or metro networks are existing in the overlapping geographical area.

The RRTS/metro rail networks ex­pe­cted to come up in the future may be own­ed and operated by the government or go­ver­nment agencies such as public sector uni­ts. Another possibility is that such futu­re RRTS/metro rail networks operate un­der the public-private partnership (PPP) model or are wholly owned by private en­tities. Meanwhile, the spectrum that will be assigned to the NCRTC for the RRTS will be used in eight corridors spread ac­ross four states: Haryana, Rajasthan, Uttar Pradesh and Delhi. Considering the future spectr­um requirement in other parts of the country, it may be prudent to keep this sp­e­c­trum reserved for captive usage for rail networks in India. Consi­dering the diverse uses of the allotted spectrum might be cost efficient as well.

To this end, the regulatory authority has invited responses from stakeholders wi­th regard to possible challenges if the sa­­me spectrum is assigned to different RRTS/metro rail networks, operating in geo­graphically separated areas/corridors in the country. Subsequently, there might be cases where more than one RRTS me­t­ro/rail network is to operate in overlapping geographical areas. With regard to this concern, TRAI, in the consultation paper, has sought the views of stakeholders on the compatibility of RRTS metro/rail networks for sharing radio access networks in overlapping areas.

Applications of RRTS

In general, the main applications of the RRTS can be categorised into four types: train ra­dio, train positioning, train remote control and train surveillance.

  • Train radio: This is used for communication between trains and tracks for signalling and traffic management. The aim is to contribute to safe train operations. Train radio provides mobile interconnection to landlines and mobile-to-mobile vo­i­ce communication, and serves as a data transmission channel within various bearer services (maintenance, emergency, tr­ain control, movement authorisation) and for providing train information to both train operators and passengers.
  • Train positioning information: This provides high-precision information ab­out the position of trains, the location of all units on the trackside, the motion pa­rameters (speed, distance) of approa­ching rolling stock, and obstacles on the tracks during normal and high speed operation.
  • Train remote: This application provides a data communication between a locomotive and a ground-based system, in or­der to control the locomotive’s engine. The remote driver can operate the locomotive via the ground system. This application enables and allows remote controlled movement of trains typically for shunting operations in depots and shunting yards, and/or for banking.
  • Train surveillance: Train surveillance sy­s­tems enable the capturing and transmission of videos of the public and trackside areas, driver cabs, passenger com­pa­r­t­ments, platforms and device mo­nitoring. A set of cameras at specific locations (front, interior, rear) can be used for low or high resolution and low or high framerate footage, depending on the event. Data may be either stored onboa­rd/lo­cally, or streamed (such as in the form of real-time video) to control centres via a dedicated radio communication system.

Licence requirements

While the authority has mandated spectrum only for captive use by the NCRTC and other RRTS/metro rail networks, to establish a wireless captive network using spe­cifically assigned spectrum, an entity should have a permission/licence under Sec­tion 4 of the Indian Telegraph Act, 1885. Such a licence may be obtained from DoT.

To this end, making the captive wireless private network permission/licence applicable  to the NCRTC and other RRTS/­met­ro rail networks could be an option. However, since the operation of rail/metro networks involves public safety and security concerns, and is not limited to a particular geographic area – given that a train may pass through an open area that in­cludes more than one licensed service area, where public cellular networks also operate – a separate category of permis­sio­ns/licences could be created for captive wi­re­less networks for train signalling syste­ms. This licensing regime should be simple and lightweight.

The consultation paper thus seeks the opinions of stakeholders regarding a per­mi­ssion/licensing regime for the operation of wireless networks for the NCRTC and other RRTS/metro rail networks. In addi­ti­on, the consultation paper seeks respon­ses regarding the possible terms and conditions for the permission/licence.

Spectrum charges

Indian Railways (IR) is using a GSM-R-based network similar to various railway networks deployed around the world. IR has been assigned 1.6 MHz of paired spectrum in the 900 MHz band on an administrative basis for captive usage of the GSM-R-based network. For the temporary spectrum assigned to the NCRTC – 1.4 MHz of paired spectrum in the 900 MHz band – spectrum charges have been calculated based on the formula-based charging applied for IR.

Earlier, in November 2021, DoT had mandated that NCRTC spectrum be used for mission-critical safety applications of signalling and train control. DoT had also mentioned that separate spectrum should be used for this, as these services involve sa­fety concerns. Further, DoT had, inter alia, requested TRAI to provide recom­m­e­n­dations on the administrative assignment of spectrum to the NCRTC. The­re­fore, the issue that now needs to be deliberated on is the sp­ectrum charging mechanism for the sp­e­c­­trum that will be assig­ned to the NCRTC and other RRTS/ metro rail networks.

Given this issue, TRAI has sought the thoughts of stakeholders regarding the decision of allotting spectrum analogous to IR. Moreover, TRAI has sought an efficient spectrum charging mechanism for the spectrum that will be assigned to the NCRTC. Mo­re­over, the consultation paper has sought opinions regarding the sp­ectrum charges applicable to the NCRTC also being made ap­­p­li­cable to other RRTS/me­tro rail networks that may come up in the future.

Anand Kumar Sah