Bringing Broadband Connectivity to Trains with Satellite Communication

Transcription

1 Bringing Broadband Connectivity to Trains with Satellite Communication White Paper Doreet Oren Director of Product Marketing Gilat Satellite Networks Gilat Satellite Networks Proprietary Information

2 Contents 1. Overview The market need The solution The basics Satellite on the Move (SOTM) - main components and challenges Low profile SOTM antenna Satellite Modems Block Up-Converter BUC Transmitter Teleport (Hub station) Case studies Case study A: Russia Case study B: Africa Case study C: Euroasia Conclusion List of Figures Figure 1 SOTM Network Overview... 5 Figure 2 Elevation angle according to location on globe vis-à-vis geostationary satellite... 7 List of Pictures Picture 1 Broadband Connectivity brought to trains... 3 Picture 2 Passengers enjoying broadband connectivity while on-the-go... 3 Picture 3 Train operation and control center... 4 Picture 4 Gilat RaySat E-7000 Low Profile Antenna... 6 Picture 5 Gilat GLT-1000 Satellite Modem... 7 Picture 6 Gilat s Wavestream Matchbox BUC... 8 Picture 7 Teleport Antenna... 8 Picture 8 Gilat RaySat E-7000 Low Profile Antenna Installed on Train Roof... 9 Picture 9 Train engineer ensures safety with collision prevention system Picture 10 High gain antenna required here to overcome electric poles obstructing LOS Gilat Satellite Networks Proprietary Information 2

3 1. Overview Imagine a passenger train travelling fast through remote uninhabited areas. Often miles and miles of forests or desolate deserts are passed with no sign of human life in site. These distant areas are usually lacking communication infrastructure as it would be too costly to provide. The train on the other hand is packed Broadband Connectivity brought to trains with people on their way to work, to visit relatives, or traveling for vacation. Each extending their life activities during the train ride; all being supported by broadband connectivity. A business woman updating a presentation just received by on her tablet, a tourist browsing the web looking for evening entertainment possibilities, a mom Skyping from her smartphone with her kid left at home, a salesman on the phone being prepared by his office for closing a deal, teenagers on Facebook keeping up with their friends, and a group of guys all excited with the live sports broadcast displayed on the large screen in the front of their car. While the passengers are doing their thing, the train operation is smooth providing security and control to ensure passenger safety with the aid of broadband communication. This is the tightly connected world we live in where communication on the move is a must. The question then is not if to provide but how to provide. The most cost effective and often the only feasible solution for broadband connectivity on the move is satellite communication. You are invited to read on to understand the market need and proposed solutions, including examples from Gilat Satellite Networks. 2. The market need Train operators are challenged to meet the growing connectivity demands for real-time information for both passenger and cargo transportation. Connectivity requirements span a wide set of services that include the well-being of the passengers by providing entertainment, business and security services, as well as enhanced train operation and control applications. Passengers enjoying broadband connectivity while on-the-go Gilat Satellite Networks Proprietary Information 3

4 Passenger communication and entertainment for long commute hours, including Internet surfing, , social networking and live web updates on news, sports and weather are becoming a must-have in many parts of the globe. A special need for on the move connectivity is apparent with train travel to global events, such as trade exhibitions or sporting events. Communication is expected by participants and at times even required by the hosting country. Another major need for continuous broadband connectivity is in the area of operation and control applications that can provide increased security and more effective train management. These applications include such essential tasks as surveillance, remote monitoring and control, hazard alerts, and collision Train operation and control center prevention. Security and regulatory standards - often government driven - are becoming stricter, requiring more stringent safety requirements. Continuous connectivity service for both passengers and train operation and control is required along the entire rail route. This route might include remotely populated areas with diverse terrain conditions. The coverage of both cellular networks and the availability of WIFI hotspots is spotty or unavailable along long train routes that often pass through uninhabited or sparsely populated areas. The ground connectivity challenge is often magnified due to topology and country regulations. The challenge therefore is to provide uninterrupted connectivity independent of terrestrial infrastructure. In addition, economic considerations need to be taken into account. Train routes pass through remote areas where it is not economical to layout communication groundwork. The high cost of installing cellular towers every few kilometers along the entire track, as well as the lengthy implementation schedule, makes this option unfeasible. Equally impractical is the option of laying out fiber or copper lines in rugged terrain. 3. The solution 3.1 The basics Satellite communications plays a vital role in the global telecommunications system. These satellites can handle communication up to large distances (continent-wide) independent of the terrain and terrestrial infrastructure Gilat Satellite Networks Proprietary Information 4

5 coverage allowing for secure & private networks. Deployment is quick and easy, no digging required; new sites can be up on the same day. Today s solution of choice for SATCOM is based on communication links with geostationary satellites that orbit the Earth directly over the equator, approximately ~36000 km (22240 miles) up. This type of satellite orbit has the advantage of appearing stationary in the same area of the sky, as viewed from a particular location on Earth. For mobile SATCOM applications tracking antennas are used to maintain the line of sight (LOS). For high data rates as required for broadband, high frequency bands (Ku/Ka) are recommended to minimize space segment cost and reduce operational expenses. The delivery of broadband communication service in a moving train is a technologically demanding challenge. There are several solutions on the market that address this challenge in different ways. Satellite communication on the Move (SOTM) is by far the most robust solution and the one that can provide the most continuous coverage. It is also at times the only option and the most cost effective alternative when other means of communication are not present. The preferred choice of SOTM solutions is dependent on many factors and careful analysis must be done to provide the optimal choice. Naturally, the geographic terrain, the environmental conditions, the train mechanics, and of course the desired applications are all key to making the appropriate solution choice that will increase revenues while delivering customer and operational value. SOTM Network Overview Gilat Satellite Networks Proprietary Information 5

6 Broadband SOTM systems provide an IP pipe in a moving environment, delivering a user experience as though one were sitting at his or her desk. Therefore, any IPbased application, such as VoIP, , or simply web browsing, can be accessed. An IP router can be implemented to give access to multiple users using different applications. This addresses the multiple simultaneous needs for both train passengers and train operation/control. It is important to note that the requirements for SOTM are markedly different than conventional stationary satellite communication. All equipment installed on the roof of the train - primarily satellite antennas - must be designed to meet aerodynamic challenges and must have a low profile to fit into low height tunnels. They must operate in low temperatures and have high resistance to shock while in motion. The antennas must be able to track the satellite, and have fast reacquisition of the satellite link in case of line of sight blockage. In addition, for the solution to be cost effective, a high gain antenna is required with adequate transmission and reception rates for effective bandwidth allocation. 3.2 Satellite Communication on the Move (SOTM) - main components and challenges A SOTM solution is comprised of distinct elements that must come together to provide a robust, secure, manageable and affordable satellite communication system. The ground system components are discussed below Low profile SOTM antenna The antenna itself is the enabling SOTM technology. The tracking antenna must be low profile, rugged, and wide reaching with a high gain to cost effectively meet the growing broadband communication needs. Physical criteria - Low profile Gilat RaySat E-7000 Low Profile Antenna A key requirement for a SOTM antenna is that it should minimize the level of aerodynamic interference and be no higher than 30cm, for safe passage through tunnels and under bridges; it also must be robust enough to operate in temperatures as low as -40 C. Low weight is required for simple transport and safe installation, eliminating the need to modify the locomotive/cabin roof. Gilat Satellite Networks Proprietary Information 6

7 High gain more throughput A high gain antenna supporting higher transmission rates enables efficient data, voice and video streaming. A high gain antenna is particularly important for SOTM to enable cost effective bandwidth allocation and high enough transmission rates to overcome signal drops due to electric poles found along the train route (when electric trains are in operation). A high gain antenna can be a key factor in reducing both capital expenditure (e.g. usage of smaller power transmitters) and operational expenses (reduced satellite space segment allocation). Elevation look angle wide coverage Due to the geostationary satellite solution discussed above, tracking of the satellite on the move requires different antenna elevation angles which are dependent on the location of the antenna relative to the equator above which the satellite is located. A wide elevation angle range can ensure maximal flexibility in choosing the satellite of operation, as well as a unified solution architecture that can be implemented over a long spread of railway tracks within the country or even within the continent Satellite Modems A satellite modem is a telecommunication earth terminal used to transmit and receive information via satellite. There are various network configuration options to best address the required information flow. The appropriate transmission method should be chosen to fit the needs and technical specifications of the application. Elevation angle according to location on globe vis-à-vis geostationary satellite Gilat GLT-1000 Satellite Modem Typically for large networks a VSAT (very small aperture terminal) is preferred. VSATs save on bandwidth by employing TDMA (time division multiplexing access) to allocate bandwidth as needed for the best return on investment. However, for smaller networks, that use fewer terminals - yet require high efficiency and high performance - a modem supporting a dedicated point to point satellite link SCPC (Single Channel per Carrier) of continuous transmission would be more cost effective and yield better results. Gilat Satellite Networks Proprietary Information 7

8 Both types of existing satellite modems have been designed for use in a fixed/stationary environment with large parabolic antennas. SOTM requires different capabilities tailored to overcome other issues. The two most important features required for SOTM modems are: Fast re-acquisition time the time required by the modem to quickly reestablish the network link after brief blockages must be short to provide a continuous uninterrupted high quality service. Intermittent blockages obstructing the line of sight can happen along the train route from a variety of sources such as trees, buildings, and stations. The satellite link needs to be reestablished quickly and automatically to provide the expected/optimal user experience. Adaptive modem waveform an adaptive modem waveform is required to keep the link during rainy weather as well as to best utilize the allocated bandwidth. Dynamic change of the modulation, coding and spreading factor during rain helps maintain the satellite link. In addition, optimal waveform implementation for a particular usage scenario will provide higher bandwidth efficiency, reducing operating costs Block Up-Converter BUC Transmitter The RF transmitter / Block Up-Converter (BUC) may appear to be a simple off- the- shelf component that can be purchased from a variety of vendors. However the BUC is a large discriminator and determining factor when selecting a SOTM system. When working within a train SOTM solution, the power, space, visibility, cost and cooling requirements Gilat s Wavestream Matchbox BUC ultimately drive the BUC selection. The BUC must be very reliable and robust, efficient, and must provide a stable gain/power within changing environmental conditions Teleport (Hub station) The teleport or hub station is the center gateway to the internet service provider (ISP). The teleport may be operated by an existing satellite network service operator or a by a private network operated by the railway company itself. For SOTM solutions, the typical hub antenna is large, over 4.5 meters to compensate for the small aperture antennas required on the moving train. The large hub antenna will maximize throughput and will ensure that the satellite link can be closed. Teleport Antenna Gilat Satellite Networks Proprietary Information 8

9 Traditional satellite communication integrators may have difficulty addressing the unique requirements of the quickly developing SOTM market. Beyond simply integrating off the shelf devices, it demands the expertise of optimizing all the critical elements. Significant field experience is therefore required in providing an end to end solution for broadband satellite communication on the move. 4. Case studies Gilat Satellite Networks has field experience in providing satellite on the move in trains, addressing an assortment of challenges and a variety of application requirements in demanding environments. The following case studies illustrate this expertise. 4.1 Case study A: Russia Background: A Russian railway company needed a solution for broadband communication on its long train routes, servicing primary business passenger routes. These routes of over 1,000 km with travel times up to 16 hours go through uninhabited areas, small villages and cities year round, operating in extremely cold temperatures. Travelling businessmen need to be able to access the Web at a minimum transmission rate of 2Mbps/0.5Mbps of unlimited traffic. Gilat RaySat E-7000 Low Profile Antenna Installed on Train Roof Overcoming the Challenges: In providing the solution, Gilat had to take into consideration the northern geographic location, far away from the equator, while ensuring flawless operation, in harsh weather conditions. To meet this challenge the low profile, high gain RaySat E-7000 antenna from Gilat was chosen because of its ability to operate successfully in temperatures reaching as low as -40 C. In addition the challenge of keeping a line of site with the geostationary satellite orbiting over the equator was overcome with the E-7000 s wide elevation angle. The technology is based on a rotating panel with a mechanical elevation range that can reach below 10. In addition the antenna is relatively light weight making installation on the train roof simpler and safe. The satellite service operators, are using two different modem types. One is providing a dedicated service with Gilat s GLT modem establishing a permanent SCPC link with high efficiency and performance. The other chose to expand their existing Gilat SkyEdge II VSAT network which was initially used only Gilat Satellite Networks Proprietary Information 9

10 for fixed sites. This expansion, allowed sharing the bandwidth across trains in a TDMA configuration. 4.2 Case study B: Africa Background: An African railway company was looking to implement a collision prevention application to provide additional security for its cargo trains due to frequent derailments and other accidents. Enhanced monitoring and control during the entire route was needed to upgrade security. Anti-collision system data, GPS data and voice had to be collected and transmitted to the network management system in the railway control center. The information on each train had to be constantly and continuously processed into a sophisticated application to prevent collision, ensuring safe and timely arrival of goods such as lumber and oil. Overcoming the Challenges: Train engineer ensures safety with collision prevention system The railway company expanded its satellite network to include a high availability Gilat SOTM communication system to provide the exact coordinates, speed and direction of the train to the operation and control center. The geographic location on the equator was addressed with Gilat s RaySat E-7000 antenna which supports a wide elevation angle. In order to maintain a line of site with the geostationary satellite, the antenna has to be positioned at a very high elevation looking angle. In addition a low profile antenna was required to be able to pass through low height tunnels. In this solution a very fast reacquisition time was required to reestablish the communication link once the train emerged from the two minute tunnel. In addition, Gilat provided a high gain 40W Wavestream Matchbox BUC (transmitter) to ensure continuous, reliable availability. 4.3 Case study C: Euroasia Background: A national railway wanted to enable on-the-go telephony and WIFI service on board its trains. These electric trains go through about 1,000 km of sparsely populated desert/steppe areas servicing popular travel routes. Business travelers are often required to save expenses and travel by train rather than use expensive air travel. Passengers were to use prepaid cards to access broadband Internet service of up to 2Mbps for , fast web searches, e- commerce and high quality VoIP service. Gilat Satellite Networks Proprietary Information 10

11 Overcoming the Challenges: The electric train is supported by electric poles every ~40-50m along the railroad. These poles pose a challenge due to an obstruction of the line of sight to the geostationary orbiting satellite, causing signal drops. A high gain antenna such as the Gilat RaySat E-7000 is needed to overcome a considerable signal level drop and to ensure continuous connectivity for the ultimate user experience. High gain antenna required here to overcome electric poles obstructing LOS This solution called for a VSAT network to allocate bandwidth as needed across trains in a TDMA configuration. Gilat s SkyEdge VSAT was chosen by a government-owned telco, which was established to meet the railway's communications needs. The antenna is connected to the VSAT which provides broadband access to the passengers via a wireless LAN distributed throughout the cabins using WiFi. This solution enhances the web browsing experience and prioritizes VoIP traffic to ensure good quality voice calls. 5. Conclusion The train industry is now becoming aware of the need to provide continuous uninterrupted broadband communication to improve operations, security and passenger experience for business and pleasure. The train lines which will provide a safer, more productive and enjoyable ride are those which will prevail in the 21st century. Satellite communication on the move (SOTM) is the proven means to achieve such connectivity along the full rail route when terrestrial infrastructure is unavailable and too costly to install. Gilat Satellite Networks has been in the business of satellite communication for the last twenty-five years, providing ground equipment and taking-on complex integration projects for both stationary and on the move applications. The train industry with its special needs and challenges is well understood by Gilat and optimally supported in the field with specialized, cost effective equipment. For more information on how to implement a broadband communication solution to address your needs and budget, please contact us: [email protected]. Gilat Satellite Networks Proprietary Information 11

12 Gilat Satellite Networks Proprietary Information This document contains information proprietary to Gilat Satellite Networks Ltd. and its affiliates and may not be reproduced in whole or in part without the express written consent of Gilat Satellite Networks Ltd. The disclosure by Gilat Satellite Networks Ltd. of information contained herein does not constitute any license or authorization to use or disclose the information, ideas or concepts presented. The contents of this document are subject to change without prior notice. Gilat Satellite Networks Proprietary Information 12