Specifications

FL-MDS-CAB.2
MOD-MDS.1 ***Confidential*** 5 of 28
STM32
Cortex-M
MCU
Antenna
A
CAN id + termination resistor
status LED
I/O and bypass connector
I/O and bypass connector
Power
supply
CAN transceiver
CAN bus
Antenna
select circuit
UART port
Debug port
24V DC
Antenna
B
HITAG RFId
reader
Figure 2. Double antenna CAB schema
3.1 Performance requirements
 The required maximum read failure rate for PCF7931 tags is 0.3 PPM (3 failed reads every 10
7
)
for both CAB versions. Failure rate is estimated with the following tests:
o on-the-fly read: consecutive read of at least 30M passages of 50 tags at standard HT TLA
speed (172.5 mm/s ± 5%) in a standard Inpeco sampling point on a test track.
o static read: at least 30M consecutive alternate readings of 2 carriers of the test Inpeco
minitrack according to the figure below (carrier tags A and B are read alternatively). The
carrier axes are aligned with the antennas’ axes, adjacent carriers do not prevent correct
readings (see the carrier C position in figure 5). A read operation is performed every 250
ms.
o The required failure rates must not be exceeded in presence of neighboring antennas.
Minimum distances in mm are shown in the potentially critic layouts shown in figure 6.