doc.: IEEE /875r1 Submission Hyun Seo Oh, ETRI July 2008 Slide 1 Radio Transmission Technology for V2V/V2I Applications Date: Authors:

doc.: IEEE /875r1 Submission Hyun Seo Oh, ETRI July 2008 Slide 2 contents V2V/V2I Applications 11 Service Requirements 22 Performance Simulation 44 Proposed Technologies 33 Summary55

doc.: IEEE /875r1 Submission Hyun Seo Oh, ETRI July 2008 Slide 3 V2V Communication : Vehicle Multi-hop Networking for Vehicle Safety V2I Communication : Bi-directional Packet Communication for ITS/Telematics Accident GPS Emergency Message Warning Message Cellular/WiBro Probe Data TSP Server Internet RSE Traffic Information V2V V2I Hopping Warning Message V2V/V2I Applications

doc.: IEEE /875r1 Submission Hyun Seo Oh, ETRI July 2008 Slide 4 V2V Service Use Case Warning Message Broadcasting Detect accident or road status in real time & broadcast warning message to the following vehicle by using vehicle to vehicle multi-hop communication Vehicle 1 Vehicle 2 Vehicle 3 ② ① ③

doc.: IEEE /875r1 Submission Hyun Seo Oh, ETRI July 2008 Slide 5 Road/Traffic Information Probe data collection Backbone Network Traffic Information Center Probe Vehicle Traffic Probe data collection/Traffic information RSE collects probe data from the vehicle periodically and provides traffic and road status information to vehicles Road/Traffic Information V2I Service Use Case

doc.: IEEE /875r1 Submission Hyun Seo Oh, ETRI July 2008 Slide 6 RSU Antenna Roadside Host Processor and Backhaul Equipment Inside Equipment Cabinet Traffic Management or Other Center Internet or Private Network Traffic Management Center Server/ Network Interface Two-way RF ITS/Telematics Application Roadside Unit (RSU) Frequency (GHz) Service Requirements Basic Requirements Communication : Broadcasting, Unicasting Mobility : Max. 200 km/h Packet Latency : < 100 msec Long packet transmission : ~1kbytes Networking : V2I or VANET

doc.: IEEE /875r1 Submission Hyun Seo Oh, ETRI July 2008 Slide 7 PreamblePayloadMidamblePayload MidamblePayload Channel estimation Equalizer Channel Estimation & Update Equalizer Channel Estimation & Update Equalizer N symbol ∙∙∙ Proposed Technologies Mid-amble based Channel Estimation in Vehicle Mobility. Conventional : Preamble or Pilot Sub-carriers based Initial Channel Estimation - Problem : Performance degraded for long packet reception because it provides only initial time and channel phase acquisition. New : Mid-amble based Channel Estimation and Tracking - Benefits : Good performance for long packet reception because it provides initial and continuous time and channel phase acquisition Mid-amble based Channel Estimation in Vehicle Mobility. Conventional : Preamble or Pilot Sub-carriers based Initial Channel Estimation - Problem : Performance degraded for long packet reception because it provides only initial time and channel phase acquisition. New : Mid-amble based Channel Estimation and Tracking - Benefits : Good performance for long packet reception because it provides initial and continuous time and channel phase acquisition

doc.: IEEE /875r1 Submission Hyun Seo Oh, ETRI July 2008 Slide 8 CSMA/CA-TDMA combined MAC with priority control Conventional : CSMA - Problem : Throughput degradation for the increased number of users New : CSMA/CA-TDMA combined MAC - Benefits : Better throughput by time slot scheduling, useful for VANET and V2I CSMA/CA-TDMA combined MAC with priority control Conventional : CSMA - Problem : Throughput degradation for the increased number of users New : CSMA/CA-TDMA combined MAC - Benefits : Better throughput by time slot scheduling, useful for VANET and V2I Proposed Technologies

doc.: IEEE /875r1 Submission Hyun Seo Oh, ETRI July 2008 Slide 9 Performance Simulation Radio Link Simulation. Transceiver model : IEEE p with Mid-amble insertion. Radio Channel Model : TDL filter model, which was proposed by GIT, USA. Comparative analysis : Performance of Preamble based or Mid-amble based channel estimation Radio Link Simulation. Transceiver model : IEEE p with Mid-amble insertion. Radio Channel Model : TDL filter model, which was proposed by GIT, USA. Comparative analysis : Performance of Preamble based or Mid-amble based channel estimation

doc.: IEEE /875r1 Submission Hyun Seo Oh, ETRI July 2008 Slide 10 Packet Length Analysis of Preamble based Estimation. If packet length is less than 40 bytes, its performance is good. However, its performance will be worse as the packet length is increasing. Long sized packet to be order of 1kbytes : needs new technology for V2I applications Packet Length Analysis of Preamble based Estimation. If packet length is less than 40 bytes, its performance is good. However, its performance will be worse as the packet length is increasing. Long sized packet to be order of 1kbytes : needs new technology for V2I applications Performance Simulation

doc.: IEEE /875r1 Submission Hyun Seo Oh, ETRI July 2008 Slide 11 Radio Link Simulation for 200 bytes packet. Fading Loss : approximated 20 dB if channel estimation is perfect. Mid-amble channel estimation performance for BPSK/16QAM modulation : approaches performance of ideal channel estimation even though it is impacted by radio channel models Radio Link Simulation for 200 bytes packet. Fading Loss : approximated 20 dB if channel estimation is perfect. Mid-amble channel estimation performance for BPSK/16QAM modulation : approaches performance of ideal channel estimation even though it is impacted by radio channel models Performance Simulation

doc.: IEEE /875r1 Submission Hyun Seo Oh, ETRI July 2008 Slide 12 Radio Link Simulation for 1 Kbytes packet. Mid-amble channel estimation for BPSK/16QAM : approaches performance of ideal channel estimation, uniform performance irrespective of modulation level Radio Link Simulation for 1 Kbytes packet. Mid-amble channel estimation for BPSK/16QAM : approaches performance of ideal channel estimation, uniform performance irrespective of modulation level Performance Simulation

doc.: IEEE /875r1 Submission Hyun Seo Oh, ETRI July 2008 Slide 13 MAC simulation PHY : a OFDM, 6Mbps fixed MAC : DCF, CSMA/CA-TDMA combined MAC Number of slot : 4 slots for CSMA/CA-TDMA combined MAC Application : CBR Traffic (Unicast, Broadcast) Simulation tool : Qualnet 4.0 version MAC simulation PHY : a OFDM, 6Mbps fixed MAC : DCF, CSMA/CA-TDMA combined MAC Number of slot : 4 slots for CSMA/CA-TDMA combined MAC Application : CBR Traffic (Unicast, Broadcast) Simulation tool : Qualnet 4.0 version 5, 10, 15, 20 unicast flows 10, , 40 broadcast flows Performance Simulation

doc.: IEEE /875r1 Submission Hyun Seo Oh, ETRI July 2008 Slide 14 Unicast Scenario Unicast CBR Flows : 5~20 Performance parameter : Throughput & Delay Unicast Scenario Unicast CBR Flows : 5~20 Performance parameter : Throughput & Delay Number of flows Throughput (bps) Number of flows Delay [sec] Performance Simulation

doc.: IEEE /875r1 Submission Hyun Seo Oh, ETRI July 2008 Slide 15 Unicast Scenario Unicast CBR Flows : 5~20 Performance parameter : No of Retransmission (RTS) Unicast Scenario Unicast CBR Flows : 5~20 Performance parameter : No of Retransmission (RTS) Number of flows No. of retransmission Node ID Information Performance Simulation

doc.: IEEE /875r1 Submission Hyun Seo Oh, ETRI July 2008 Slide 16 Broadcast scenario Broadcast CBR Flows : 10 ~40 Performance parameter : Throughput & Delay Broadcast scenario Broadcast CBR Flows : 10 ~40 Performance parameter : Throughput & Delay Number of flows Throughput (bps) Number of flows Delay (sec) Performance Simulation

doc.: IEEE /875r1 Submission Hyun Seo Oh, ETRI July 2008 Slide 17 Vehicle Services will be categorized into –V2V based Vehicle Safety Service : Intersection Collision Avoidance –V2I bases Convergence Service : ITS/Telematics/USN Convergence Service V2V/V2I Communication has basic requirements –High Mobility : 200 Km/h –Low Latency : <100 msec –Long Packet Transmission : ~ 1kbytes –Networking : VANET or V2I Propose New Challenging Technologies -Mid-amble based Channel estimation for long packet -CSMA/CA-TDMA combined MAC for service priority Summary