Overview

BLD

General

BLD (Balise Level & Error Detector) is a device that is installed at the bottom of the ITX-Saemaeul and metropolitan trains and it detects the level and error of the balise to be installed on the track while the train is in revenue service in order to check for abnormalities of balise operation. The balise real time inspection data measured by the BLD is transmitted to the ground inspection center via LTE wireless communication through the main server of the on-board integration device located on the train.

Specification

Detection Speed 300km/h
Telemetering Frequency 27.095MHz
Data Receive Frequncy 4.234MHz
Data Bit Rate 564.5 kbps
Modulation Type FSK(frequency Shift Keying)
Detection Telegram Frame 2~7 Frame
Antenna Transmit, Receive seperately
Size Control Module : 340x162x380mm
Antenna : 436x285x130mm
Input Votage AC220V
Weight (BLD & Bracket) 55kg
Operation Temperature -40℃~+70℃
Interface between Control
module & Antenna		 75Ω coaxial cable
Outside Interface Ethernet(TCP/IP) 1port
Serial RS485 1port

Detection Performance

Detection Item Performance Contents
Balise Detection Identify receiving frequency Identify detection of frequency on antenna
Telegram Identify receiving telegram Identify telegram of balise
Balise ID ID of a designated balise It should be same
Current Level More than 100mA Receving frequency
Center Frequency 4.059 ~ 4.409 MHz FFFIS Subset 085 specification
Frequency Deviation 262.48 ~ 302.0 KHz FFFIS Subset 085 specification
Amplitude -2.0 ~ +1.5dB FFFIS Subset 085 specification
Data Communication 550.368~578.592Kbits FFFIS Subset 085 specification