Optimization of DATA Transmission for Transport Sector User case, TMB

1. Optimization of DATA Transmission for Transport SectorUser case, TMB David LumbrerasProject Area Manager

2. In this presentation: • User requirements • High efficiency in AVL Systems • Comparing methods • An example: TMB case

3. Fleet Manager Requirements: • Traffic Bus Regulation. • Frequency Improvement. • Customer Service. • Investment Optimization. • Passengers Safety

4. How to do it? • Voice Communications with the Control Centre. • Half-duplex and duplex voice calls. • Status and short data transmission. • Vehicle sensors transmission. • MMI integrated on driver’s dashboard. • Interaction with passenger information system. • GPS-based location system.

5. How often is needed? • Data User Requirements: • Continuous Actualization of Data in Control Centre. • Normally 20/ 30 second each Terminal.

6. User Requirements

7. Bus on-board equipment Example: CONFIGURATION STRUCTURE Control unit Bus driver’s MMI TETRA MS engine, speed, doors... Telemetry sensors PEI Bus driver’s audio system control Audio interface - PTT - Emergency button - Call request Billing system data Passenger information system DISPLAY Ambience listening microphone Hands-free audio kit Other peripherals Handset

8. Driver’s MMI console Bus on-board equipment Example: INSTALLATION DETAILS Bus system interface Control unit TETRA radio Passenger information system Micro speaker & hands-free mic

9. Looking for the most efficient way for DATA TRANSMISSION with TETRA technology

10. MCCH Occupation Nº slots 4 100% 3 75% 2 50% 49% 1 (MCCH) 25% Type of service Random SDS Random PD Polling SDS Polling PD High efficiency in AVL, Comparing Methods • In this type of scenario it is necessary to analyse carefully the geographic positioning as the stronger requirement. • Short Data Messages (SDS) comparing to Packet Data Protocol (PDP), the conclusions are: With these conclusions, we are going to work with SDS polling to obtain the geographic positioning. Scenario example • 500 buses. • 30 seconds of latency for all buses. • 20 bytes of information size. • 3 coverage sites (SBS).

11. Mobile in MCCH SwMi D_STATUS_REQ 1/2 slot downlink Status REQUEST+ slot granting (1). ACK + SDS_DATA 1 slot uplink Ack to Status + SDS data (160 bits) ACK 1/2 slot downlink SwMi acknowledge System considerations. Terminal considerations. High efficiency in AVL, Comparing Methods • With the standard SDS procedure the requirement for the network is still strong. • So now, it is necessary to think beyond the TETRA technology. • New option improving the efficiency. • Packets used in MCCH to transmit 20 bytes of data.

12. MCCH Occupation Nº slots 4 100% 3 75% 2 50% 49% 1 (MCCH) 25% The best one Type of service Optimised Polling SDS Random SDS Random PD Polling SDS Polling PD High efficiency in AVL, Comparing Methods • New optimised polling SDS is the best solution to this type of application. Scenario example • 500 buses. • 30 seconds of latency for all buses. • 20 bytes of information size. • 3 coverage sites (SBS).

13. TMB User case 8 SBS´s 1300 buses

14. High efficiency in AVL, Comparing Methods • With the best service selected… Now it is necessary to think how we are going to synchronize the different CCHs. • Here using 1MCCH and 3 SCCH per SBS: • 15% of the control channel is used for geographic positioning. • To obtain this percentage it is necessary to synchronise all CCHs Real scenario example • 1300 buses. • 20 seconds of latency for all buses. • 20 bytes of information size. • 8 coverage sites (SBS).

15. TMB user case, High efficiency in AVL Synchronising the polling means... ...obtaining following figures: • 8 SBS x 4 CCHs = 24 CCHs to request the bus position • 1300 buses / ( 20 seconds x 24 CCHs ) = 3 buses per second per CCH Doing this polling is possible to obtain success with the application.

16. TMB user case, High efficiency in AVL Synchronising the polling means... The problem is: External Application has not the capability to know where is located every bus in every second. • So for this reason Infrastructure manufacturers have to give the synchronism solution. • In that case the SwMi has to give to the applications provider several commands to introduce the buses to be polling, then… ..... polling answer will come from the SwMi Automatically.

17. TMB user case, High efficiency in AVL Commands used by the application provider: NEBULA OUTPUT COMMANDS User Application List of commands needed to manage this application: • AVL-ADD-ISSI • AVL-DEL-ISSI • AVL-START-POLLING • AVL-STOP-POLLING • AVL-GET-POSITION

18. This three ISSI lines will be sent to poll the buses in one second In 20 seconds all ISSIs on the table have to be sent to the base stations to poll the complete buses fleet TMB user case, High efficiency in AVL How the SwMi uses the ISSI list to poll at same time every CCH? Real time operative system. SwMi knows where all buses are placed so it can request them as same time with an internal table.

19. TMB user case, High efficiency in AVL • Conclusions: • This solution can save around 60% of the channels in the network, with respect to the other alternatives • Only synchronized polling generated by the SwMi can manage with success this amount of data traffic • Thinking beyond the TETRA technology manufacturers can give to the customers the final solution

20. Optimization of DATA Transmission for Transport SectorUser case, TMBThank you for your attention David LumbrerasProject Area Manager