The signals are the latest leads in a huge, multinational hunt for Flight 370. Investigators have so far been unable to say why the plane flew far off course or where exactly it ended up.
Also yesterday, a Chinese air force plane spotted a number of white floating objects in the search area.
The plane photographed the objects over a period of 20 minutes after spotting them at 11:05 local time. The detection has been reported to the JACC.
Some 10 military planes, two civil jets and 13 ships took part in today's search operations to trace the plane.
The search area is approximately 216,000 square km, about 2,000 km northwest of Perth.
It is about 300 km farther from the western coastal city than the area searched on the day before.
The mystery of the missing plane continued to baffle aviation and security authorities who have so far not succeeded in tracking the aircraft despite deploying hi-tech radar and other gadgets.
The desperate efforts to trace the signals come as new details emerged about the missing plane's likely path on the night it vanished.
More detail has been added to the flight path calculated by investigators, a senior Malaysian government source told CNN.
After reviewing radar track data from neighbouring countries, officials have concluded that the passenger jet curved north of Indonesia before turning south toward the southern Indian Ocean.
Its path took it around Indonesian airspace.
