Operations and Maintenance Manual

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JANUS

Multi-Protocol Reader Ver. 2: Maintenance Instructions

Confidential UM 360463-202: A12 (Draft) Page 133 of 291

These drawings and specifications contain confidential and proprietary information and are the property of Kapsch TrafficCom Canada Inc. and are issued in strict

confidence and will be kept confidential and used solely for the purpose intended and for no other purpose and shall not be transmitted, reproduced, copied, and/or

used as the basis for manufacture or sale of apparatus unless otherwise agreed to in writing by Kapsch TrafficCom Canada Inc.

FILE: MPR2_OPERATIONS_AND_MAINTENANCE-MANUAL_REV A12.DOCX 05/08/2014 11:24

Kapsch TrafficCom

4. THEORY OF OPERATIONS

This section offers a more detailed overview of the Reader components than the introductory overview

provided in Overview Section 2 page 24.

Multi-protocol Readers can communicate with both active and passive OBUs. The Reader uses a

combination of Time Division Multiplexed (TDM) and Frequency Division Multiplexed (FDM) periods to

read active and passive OBUs respectively. Each MRFM-S and antenna pair create a RF coverage

zone on the roadway. The antennas are situated to create overlapping coverage zones between

channels. For high speed lanes, one reader can support 5 channels. When required, multiple readers

can be synced together to support additional channels. The reader processes the OBU information

and provides transaction reports to the Lane Controller interfaces. When required, the reader can write

data to the OBU.

Active OBUs

Active OBUs are battery powered and transmit a signal to the Reader antennas. As a vehicle equipped

with an active OBU approaches a toll plaza, the OBU receives a trigger signal from the Tx antenna.

The OBU then starts transmitting data, which is received by the Rx antenna.

The MRFM-S decode the active OBU signal and passes the data to the CTM, which processes and

logs the OBU data and then sends the information to the Lane Controllers (LCs). The Reader may also

send data back to the active OBUs, such as an updated toll account balance.

Passive OBUs

Passive tags are not battery powered and cannot transmit a signal. As a vehicle equipped with a

passive OBU approaches the antenna, the OBU receives a transmit signal from the antenna. This

signal is then reflected from the passive OBU back to the antenna. The reflected signal is uniquely

modulated by each passive OBU, allowing the OBU to be identified.

The MRFM-S decodes the passive OBU signal and passes the date to the CTM which processes and

logs the OBU data and then sends the information to the Lane Controllers (LCs). The Reader may

also send data back to the active OBUs, such as an updated toll account balance..

Capture zones

The capture zone is the area of antenna RF coverage. An antenna can communicate with an OBU

once the OBU enters the antenna’s capture zone. These capture zones and the number of antennas

required per lane varies depending on the lane configuration.

Note: Installation on these type of lanes is assessed by Kapsch Personnel prior to deployment in order

to validate customer expectations and performance.