BTS, Bangkok’s main Skytrain operator, has been advised to change the spectrum band it uses for its signaling system after it was discovered that the band it was using was experiencing interference from a mobile phone network.
Issues with the signaling system first came to light earlier this month when commuters in the capital were delayed multiple times due to signaling failures on the network.
A subsequent investigation by the National Broadcasting and Telecommunications Commission found that the BTS signaling system operated at 2400MHz spectrum band while spectrum used by mobile operator DTAC operated on the 2310MHz-2370MHz band.
While there is a 30MHz difference between the bands which should, in theory, prevent interference, the NBTC found that the gap was not enough.
The BTS has been told they should switch to the 2480MHz-2495MHz spectrum band as soon as possible.