Previous - unsuccessful - launches have been criticised as breaches of a UN ban on North Korean ballistic missile tests.
The announcement is likely to increase tensions with North Korea's neighbours, with a presidential election scheduled for 19 December in South Korea.
North Korea's most recent rocket launch, in April, was a failure.
The US, Japan and South Korea said the rocket flew only for a short time before breaking up and crashing into waters off the Korean peninsula.
North Korean scientists and technicians had now "analysed the mistakes" of the April launch, the Korean Committee for Space Technology said, via KCNA.
There had been recent speculation that North Korea would attempt another launch soon, with a UN Security Council committee on Thursday warning the country against such a move.
Voice of Russia, AFP, BBC
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