The field of invention belongs to the class of products that protect Railway assets and human lives. The driver of a train pilots his train, solely on the basis of information conveyed to him through the signals on the Track. He is also unaware of trains in front of him or behind him, beyond what his eyes can see. Because of the high mass and velocity of the train, there is no possibility of stopping the train within a short distance.
Train accidents due to collisions can occur and close to stations, i.e. within the station signaling limits and also between block sections.
One of the causes of rail accidents close to Railway Stations is due to train drivers overshooting a Red Sigpal. In Railway terminology this is referred to as SPAD (Signal Passing At Danger). There is therefore a need for a reliable system that will give protection from SPAD and also in the interests of avoiding accidents, a system that will keep the Station Master and the Train Driver relevant information about trains in the vicinity. The system is to give warning about any impending accident like situation and alert a train driver about the aspect of the signal ahead (to avoid SPAD) or any hazard ahead. In case the driver ignores this warning, the system should take control and apply the brakes to prevent a mishap. This mishap can be a derailment or collision with another train occupying the same track, or an obstruction at a level crossing.
Anti Collision Devices that are available use satellite based GPS information to determine train position and predictive software algorithms to prevent collisions between trains. Each train transmits its position so that trains within a radius of 3 Kilometers receive it and take action. Positional accuracy of GPS is not sufficient enough to distinguish between adjacent tracks, when trains are moving at high speeds. GPS link also fail when the train track passes through shadow regions caused by tall buildings, canyons, valleys, tunnels etc,. Confusion therefore arises about the track identity and in many cases, when trains in opposite directions are on adjacent tracks, the system will needlessly stop both

trains. Also, the system can fail to prevent an accident when two trains are on the same track, because the system can be fooled into thinking that they are on different tracks, due to lack of positive track identification. Since the GPS based system, does not derive complete inputs on the status of signals ahead, there is no means to protect trains against collisions occurring due to Drivers Passing Signal at Danger (SPAD). Accidents due to SPAD, are the major cause of accidents within the station limits. Efforts to overcome this problem have not met with much success.
The European Train Protection System (ETCS), provides onboard signaling and automatic braking to avoid accidents due to SPAD. Track identity and train position are established using expensive Eurobalises. Wireless communication is one way and there is no provision for control of the train from the station or controller. There is no provision for warnings at manned and unmanned level crossings. There is no provision for the driver or the onboard equipment to know about other trains in the vicinity, to take action in case of an impending accident like situation.
The "Extended Range Train Control Systems" ensures protection and control of trains between stations and within station sections. It can be used on all types of trains. It can also be used in areas where Overhead Power for Electric Traction (Electric trains) is available and also where electric traction is not available (Diesel Engine Trains).
The said invention considers all the types of collisions and accidents that can occur due to a variety of reasons including failure in block working. It also provides protection for the train against accidents due to SPAD and ensures safety of passengers, freight and railway assets.

The ERTCS operates within the framework of normal block working between stations and within the framework of normal interlocking practices being followed by the Railways.
The system does not use satellite based GPS information for train location and instead uses stationary sleeper mounted or other track based wireless devices, to transfer information on exact location and positive identity of the track on which the train is running on. The ERTCS does not allow trains to communicate directly with each other.
The said invention is an Extended Range Train Control System capable of providing a Two Level, Train Control and Protection comprising Track Modules, Onboard Modules, Station Modules and Level Crossing Modules, with appropriate software programs, wirelessly interconnected and interacting with each other to perform the task of avoiding train collisions of various types, including accidents caused by SPAD and accidents at level crossings, by means of two way communication and information exchange between the train and the next station ahead, and by making the Station broadcast relevant information to all trains and level crossings in its purview.
The General Arrangement of the Modules that comprise the "EXTENDED RANGE TRAIN CONTROL SYSTEM (ERTCS )" is shown in Fig-1 It consists of Trackside Modules (1), an Onboard Module (2), Station Modules (3) and Level Crossing Module (4)
The "EXTENDED RANGE TRAIN CONTROL SYSTEM" refers to a group of wirelessly (11) interconnected modules, performing specific functions, located inside the train (5), on the sleepers (6) and at the stations (7). They interact with each other and perform the task of avoiding train collisions in various forms. The wireless communication method is as selected from GSM-R, GSM, Data Radio inVHF/UHF, CDMA, Satellite Communication, and WiMax. This microprocessor based system also takes corrective action when the train driver

ignores a Red Signal (8) to stop, or ignores any other signal meant to limit the speed of the train to a specified speed. The invention also ensures that collisions with road vehicles at level crossings (9) are avoided by providing an audio visual alarm (10) for the road user. The invention also gives information to the driver of the train about trains on the same track and if an accident or collision like situation is developing, gives warning to the driver. The invention takes control of the train brakes, if the driver fails to respond, in a preset time interval.
The Track Module (1) as shown in Fig(2) is a commercially available low cost, sleeper mounted wireless device to transfer information on exact geographic location its own identity number and the track identity. The Track Module is also known as a Tag, faces the sky. This device can be fixed as selected from being embedded into the Sleeper (2), between Sleepers or bolted onto the exposed face of the Sleeper. The Tag is programmed with its own identity number, the identity of the track on which it is mounted and also the exact geographical co-ordinates, i.e. latitude and longitude and any other information that may be required by a Train passing over it. These Tags are always used in pairs on adjacent Sleepers, This apart from giving confirmation on the direction the train is traveling, also provides for redundancy and availability that is very important in such systems. Track Modules are placed at every signal and at predetermined intervals along the track.
The Onboard Module shown in Fig (3) is an embedded microprocessor based electronic- device consisting of a commercially available Tag Reader (1) that is fitted to the underside of the train and which picks up the information wirelessly from the Track Module when the train passes over it. The core of the Onboard Module is the Microprocessor^), that acquires input from the Tag Reader(), Wireless Transmitter and Receiver(3), The train roof mounted Antennae (6) the train Odometer(4) and the Driver Machine Interfaced). Onboard Odometry is used to determine the train position between two Track Module installations.

Information from the Tag Reader, Odometer along with other inputs are processed and transmitted wirelessly to the Station Module. This information will typically be:
• Train position Co-ordinates - Latitude and Longitude.
• Train identity.
• Track Identity
• Train integrity.
• Train speed.
• Train direction.
• Time stamp.
This information is updated and transmitted every 5 seconds or less to the Station Module of the Station Ahead. The route which the train is to travel and the locations of the Track Modules, Level Crossings, Stations and Signals that the train is expected to encounter is preprogrammed into the system. The information of the speeds that the train is expected to maintain at any point of time is also graphically displayed to the driver.
The Onboard Module receives the aspect of the Signal ahead and displays the same to the train driver, so that the driver the driver can take suitable action. In case the driver is going beyond the permissible speed dictated by the aspect of the Signal ahead, the driver is alerted. The Onboard Module also receives the position and speed of any other train occupying the same track. The ERTCS compares the speed, direction and distance about the other train on the same track and if it is less than the recommended distance, alerts the driver of the train. The Driver has to acknowledge this alarm thro an Acknowledge Button provided. In case the driver ignores the alert, the ERTCS takes control of the speed and applies the brakes of the train to avoid a collision.

The Automatic Braking Unit(7) interfaces the microprocessor with the braking system of the train. A braking curve is dynamically created by the microprocessor, based on the target distance available for braking. The ERTCS applies the regular Service Brakes or the Emergency Brakes, depending on the target distance available.
A separate subsystem ensures integrity of the train and alerts the driver when train parting accidentally happens. There is also provision for the Driver to send an SOS to the Station (7), in case of Derailment or any other catastrophe.
A complete log of the train movement and drivers actions is automatically maintained by the Data Logger(8), and this information can be downloaded into the appropriate media at the end of the journey. This media can be a Smart Card. The Data Logger has a provision for recording on a Smart Card. The Smart Card is also used to initialize the Onboard Module at the start of the journey, and contains the Identity of the train Driver and other relevant information
The ERTCS draws its electrical power from the train into the Power Supply (9) sub module. The Power Supply sub module provides voltage and currents as required by the other sub modules of the ERTCS.
The Station Module shown in fig(4) is an embedded microprocessor (5) based electronic device that gets inputs from the Station Interlocking System Interface(l) and the Wireless Transmitter and Receiver(2) and external Antenna(3). The Station Module receives information from the Onboard Modules of all the Trains in the station section and of trains approaching the station in the block sections, at least once in 5 seconds.
All this information is processed and the actual position of each train in the station section, with Train Identity, Track Identity and aspect of Signals is displayed on the Video Display along with its speed. The information is seen on

the Video Display through the Video & Keyboard (4) sub module, The microprocessor computes the position and path of the trains and based on the information from the Station Interlocking System, the position and speed of the trains and gives an audio visual warning on the VDU, to the Station Master/Controller if a hazardous situation is likely to occur.
The hazardous situations that are possible are :
Collisions due to SPAD
Head On Collisions
Rear End Collisions
Side Collisions at Crossings
Collisions due to Derailment.
Collisions due to Train Parting
If the Station Master/Train Controller perceives an accident like situation
developing, he can communicate his instructions directly to the train drivers to
take counter action to avoid an accident. This is an emergency provision given in
the system for the Station Module to take control of the braking system of the
train, if the Driver does not acknowledge and respond to attempts made to contact
him.
The Station Module transmits the following information, using the track ID as the
reference
• Station Identity
• Track identity
• Train identity.
• Train position co-ordinates - Latitude and Longitude.
• Train integrity.
• Train speed.
• Train direction.
• Aspect of Signals Ahead
• Time stamp.

This information pertaining to trains is wirelessly transmitted considering one Track Identity at a time and is updated at a preset periodic interval of less than 5 seconds. In other words, all the Trains in the vicinity of the Station get an update of the position, speed and direction of any other train on the same track, every 5 seconds or less,
A complete log of the train movement of all trains in the yard and the actions taken by the Station Module is automatically maintained by the Data Logger(6), and this information can be downloaded into the appropriate media at die end of the day or at any interval, through appropriate ports provided.
The ERTCS draws its electrical power from the Station Power into the Power Supply(7) sub module. The Power Supply sub module provides voltage and currents as required by the other sub modules of the ERTCS. It also carries its own emergency reserve power battery.
The Level Crossing Module as shown in Fig(5) is an embedded microprocessor based electronic device that receives input from the Station Modules through its Wireless Transmitter and ReceiverQ) and external Antenna(2). Information on Trains is obtained from the Station Modules in Stations, on both sides of the Level Crossing, once every 5 seconds or less. The Microprocessor (3) computes the position and speed of the trains approaching the Level Crossing and Triggers an Audio Visual Alarm(4) consisting of a hooter and warning lights fixed so that it is clearly visible to the road user, approximately one minute before the arrival of the train at the Level Crossing. Shutting off the Audio Visual Warning is done based on the position of the trains which is updated every 5 seconds or less.
An additional sub module called Gateman Unit(5) is provided for manned gates, where the Gateman can send an SOS message to the Station Module, using an

Emergency Button (6) in case of an emergency, when there is an obstruction on the tracks.
A complete log of the train movement through the Level Crossing Gate and the periodic functioning of the Audio Visual Units are automatically maintained by the Data Logger(7), and this information can be downloaded into the appropriate media at any intervals, through appropriate ports provided.
The ERTCS draws its electrical power from the Railway mains into its Power Supply(8) sub module. The Power Supply sub module provides voltage and currents as required by the other sub modules of the ERTCS.
Fig-6 is an embodiment of the invention, used in a typical 2 line, 4 road station. The figure shows a typical 2 line, 4 road Station (1), with 2 main lines and 2 loop lines, with appropriate points, crossings and cross-overs. Signals meant for trains entering and leaving the station are also shown. The demarcation between the Station Sections (1), (2) , (3) and the Block Sections (4), (5) are clearly shown. Level Crossings (6), (7), Track ID (8), (9), (10), (11), (12), (13) and Trains (14) , (15), (16) (17) are shown. Train (14) on track (8) and Train (16) on track (11) are entering into the Station Section (1) from Block Sections (4) and (5) respectively. Train (15) on Track (10) and train (17) on Track (12) are already at the Station (1).
Train (14) has left the Station Section (3), towards its destination station (1). Train (14) goes over a Track Module in Block Section (4) and collects information on Track ID (8) & its Location and wirelessly transmits this along with other relevant information. The destination Station(l), receives this information. The Station Module also receives similar information from the other trains (15), (16) and (17). The Video Display Unit of the Station Module

shows the position of all the tracks, signals and trains. The status of the trains is ascertained and updated on the screen every 5 seconds or less.
The Station Module retransmits this information, with additional information, to all trains (14), (15), (16), (17) and Level Crossings (6) and (7).
Level Crossing Modules at Level Crossing (6)and (7) pick up the coordinates, speed and direction of the trains approaching the LC gates. The Level Crossing Module, computes the time taken for the train to reach the Level Crossing and activates the Audio Video alarm for the road user about one minute before the train crosses the Level Crossing. Since the trains are transmitting their positions and track identity every 5 seconds or less, the Level Crossing Module shuts off the Alarm after the train has crossed the Level Crossing, based on fresh information from the Station Module.
By the time Train (14) reaches the Distant Signal (18) of Station (1), the Aspect of this Signal has already been displayed to the train driver on the Driver Machine Interface Display of the Onboard Module. The driver should react and depending on the aspect of the signal ahead, has to continue, slow down to recommended speeds or stop. Failure to do so will trigger an alarm on the Display. If the Driver fails to respond in a preset time, the Automatic Braking Unit of the Onboard Module takes over the braking system of the train to either regulate the speed or stop the train.
Train (14) will therefore enter Track (9) in the Station (1), at a regulated speed and depending on the aspect of the Starter (19) and Advanced Starter (20) on Track (9), the train driver will proceed or stop. When train (14) leaves Station Section (1), the Track Identification (8) in Block Section (5) is again picked up. Accidents due to SPAD are eliminated,

In this scheme, the control of the train is always with the station which the train is approaching. I.e. the destination station. Since Train (14) has left Station Section (1), Control from Station Module at Station(l) is handed over to Station Module at the destination Station Section (2), after Station (2) has confirmed that block section (5) is clear.
If by any chance there is a failure in the Block working of Block Section (5), and there is still a train on Track (8) of Block Section (5), this information will be picked up by Train (14), based on transmission from Station (2). The Onboard Module warns the Driver of Train (14) to apply brakes, or if the driver ignores, goes into automatic braking mode to bring the train to a halt. The Driver then pilots the train as per regular train working rules.
Similarly Train (16), leaving Station Section (2), will move into Block Section (5), Track (11) and will send and receive information from Station Module at Station (1) which is the destination station.
Safe movement of Trains (15) and (17) is achieved through Signals from the signaling interlocking system of Station (1). Protection from SPAD is ensured by the Onboard System. Once they leave the Station section, control is handed over to the destination stations.
It can be seen that there is a comprehensive and dual level of control and protection for trains operating under the ERTCS. First level at the Onboard Module level and the second level at the Station Module level.
Fig-7 is an embodiment of the invention, used in a typical single line station.
The figure shows a typical single line Station (1), with one main line (6), and two loop lines, with appropriate points, crossings and cross-overs. Signals for trains

entering and leaving the station are shown. The demarcation between the Station Sections (1), (3) and the Block Section (2) are clearly shown. The Track Identity of the Main line outside the Station Section is (5). There are two Trains (3) and (4) respectively.
Trains (3) is on main line (5) proceeding towards Station Section (3). Train (4) is on the loop line (7) Station (3).
Train (3) has left the Station Section (1), towards its destination Station (2). The movement of the train into the Station Section (3) is similar to what is described in Fig-6. Train (3) will therefore enter Station Section (3), at a regulated speed and depending on the aspect of the Starter and Advanced Starter, the train driver will proceed or stop. Accidents due to SPAD are eliminated.
Since it is a single line section, Train (4) on Track (7) in Station (3) will have to travel to Station (1), on the same track. After Train (4) has safely arrived at Station (3), communication between Station (l)and Station (3) is established via Block Instruments and line clearance is given for Train D to proceed towards Station (1) and is acknowledged as per Block Working rules. The Station Interlocking system sets the routes. Train (4) is leaving Station Section (3), Control from Station Module at Station (3) is handed over to Station Module at Station (1), after Station (3) has confirmed that Block Section (2) is clear. In this scheme, the control of the train is always with the station which the train is approaching. I.e. the destination station
If by any chance there is a failure in the Block working of Block Section (2). and there is still a Train on Track (5) of Block Section (2), this information will be picked up by Train (4), based on transmission from Station (1). The Onboard Module warns the Driver of Train (4) to apply brakes, or applies brakes to bring the train to a halt. The Driver then pilots the train as per regular train working rules.

It can be seen that there is a comprehensive and dual level of control and protection for trains operating under the ERTCS. First level at the Onboard Module level and the second level at the Station Module level.
Fig-8 is an embodiment of the invention used in typical automatic block working sections.
The figure shows a typical 2 line, Automatic Signaling Section between Station Section (1) and (2), with appropriate Signals for trains entering and leaving the stations shown. The demarcation between the Station Sections (1) and (2) and the Automatic Block Sections (3), (4), (5), (6), (7) and (8) are clearly shown. There are 2 Trains with Train Identity (9) and (10).
Train (9) on Track (11) is leaving the station section and is approaching Track(12) in Automatic Block Section (3). Train (10) on Track (13) is in Automatic Block Section (7) and is approaching Automatic Block Section (8).
Train (9) is proceeding towards its destination Station(2) and crosses the Starter Signal (14) and goes over a Track Module Tag (15) in Block Section (3) and collects information on Track ID (12) & its Location and wirelessly transmits this along with other relevant information. Station (2) as the destination station receives this information. The Station Module at Station (2) also receives similar information from the other Train (10), in Auto Block Section (7). The Video Display Unit of the Station Module shows the position of all the tracks, signals and trains. The status of the trains is ascertained and refreshed on the screen every 5 seconds or less.
The Station Module retransmits this information, with additional information to Trains (9) and (10).

The movement of Train (9) into the Auto Block Sections ahead is controlled by the aspects of the signals ahead as per automatic block working rules. Train (9) transmits its track Identity and location every 5 seconds or less to the Station Module at Station (2), which in turn transmits all relevant information, about all the trains on that line.
When train (10) reaches the Distant Signal (16) of Station (2), the Aspect of this Signal has already been displayed to the train driver on the Driver Machine Interface Display of the Onboard Module. The driver should react and depending on the aspect of the signal ahead, has to continue, slow down to recommended speeds or stop. Failure to do so will trigger an alarm on the Display , and if the Driver fails to respond in a preset time, the Automatic Braking Unit of the Onboard Module takes over the braking system of the train to either regulate the speed or stop the train.
Train (10) will therefore enter Station Section (2), at a regulated speed and depending on the aspect of the Starter and Advanced Starter in Station (2), the train driver will proceed or stop. Accidents due to SPAD are eliminated.
If by any chance there is a failure in the Automatic Block working, there is a chance that there is still a train on the Block Section ahead. The Onboard Module of each train automatically checks the position and speed of trains ahead. If the distance of the train in front is less than a specified distance, an alarm is given to the train driver. The driver should react and has to stop. Failure to do so will trigger an alarm on the Display, and if the Driver fails to respond in a preset time, the Automatic Braking Unit of the Onboard Module takes over the braking system of the train to stop the train. The Driver then pilots the train as per regular train working rules.
At the Station, the specific position of all trains is displayed by the Station Module. In die event of a failure in Automatic Block Working, and if the

distances between trains is less than a specified distance, an alarm is sounded. If the Station master/Train Controller perceives an accident like situation developing, he can communicate his instructions directly to the train drivers to take counter action to avoid an accident There is an emergency provision given in the Station Module to brake the train.
It can be seen that there is a comprehensive and dual level of protection for trains operating under the ERTCS. First level at the Onboard Module level and the second level at the Station Module level.

We Claim:
1: An Extended Range Train Control System capable of providing a Two Level, Train Control and Protection comprising Track Modules, Onboard Modules, Station Modules and Level Crossing Modules, with appropriate software programs, wirelessly interconnected and interacting with each other to perform the task of avoiding train collisions of various types, including accidents caused by SPAD and accidents at level crossings, by means of two way communication and information exchange between the train and the next station ahead, and by making the Station broadcast relevant information to all trains and level crossings in its purview.
2: The Train Control System as claimed in Claim 1, the First level of Train Protection and Control is capable of achieving by means of Onboard Module taking over the braking control of the train, in case the driver does not respond to a hazardous situation and the Second level is by the Station Module taking over the control of the train in an emergency.
3: The Train Control System as claimed in Claim 1, the microprocessor based Onboard Module having two way wireless communication with the station ahead to whom it transmits its location, track identity, speed and other relevant information and capable of providing the train driver, information on trains in the vicinity, information about the status of signals ahead and a means for stopping or controlling the speed of the train if the driver does not acknowledge and act, after being warned of an impending hazard, based on information received from the Station Module, with an emergency feature for stopping the train from the Station.
4: The Train Control System as claimed in Claim 1, the microprocessor based Station Module capable of acquiring input from the Station Interlocking System

and has two way wireless communication with the trains in its purview, to whom it broadcasts information on Signal aspect ahead, their geographic position, track identity, direction and speed and having means for broadcasting the said information to level crossings in the purview of that station,
5: The Train Control System as claimed in Claim 1, the Station Module wherein the means arc provided to view the position and speed of all trains in the purview of that station on a Video Display by the Station Master or Train Controller and communicate emergency information to OIK: or more trains, if an accident like situation is foreseen between any trains, with a provision for emergency braking of any train by sending a wireless command to the Train Onboard Module.
6: The Train Control System as claimed in Claim 1, the microprocessor based Level Crossing Module capable of acquiring wireless inputs from the Station Modules on both sides in that section about approaching trains, and switches on an Audio Visual warning for the Road User, at least one minute before arrival of trains at the level crossing, with a provision in Manned Level Crossings for sending an SOS to the Stations if there is an obstruction on the tracks.
7: The "Extended Range Train Protection System" according to any of the claims from 1 to 7, substantially as herein described with reference to and as shown in figures 1 to 8 of the accompanying drawings.