At a press conference in the British capital, the channel's director and editor-in-chief Ali Asghar Ramezanpoor said "Raha" would be the "first independent channel that belongs to Iranian people.
"There are channels in Persian -- like BBC or Voice of America -- but they are from others countries, not Iranian people," added Ramezanpoor, a former deputy minister in the Ministry of Culture and Islamic Guidance.
The channel is funded by Amir Hossein Jahashahi, founder of opposition movement Green Wave. He outlined how the channel would challenge the regime of President Mahmoud Ahmadinejad.
"Raha TV is the TV for change because this regime is immoral, inhuman and unreasonable," he said, adding that transition had to come "from inside, by Iranian people".
The businessman also praised Al-Jazeera and Al-Arabiya for doing "a really big job to help the Arab people" during the uprisings sweeping the Middle East. The "free and independent" channel will begin its daily broadcast at 1630 GMT with a 30-minute news bulletin followed by three-and-a-half hours of arts, culture and sports.
The transmissions will be available in Iran via satellite and online. Programmes will be broadcast several times each day to make it more difficult for the regime to jam the signal. Raha, which means "to free" in Persian, will employ 40 people in London and will also rely on a network of around 20 freelancers in Iran, according to its founders.
Jahashahi said Raha "would be open to all opposition, reformist and non-reformist, to all people who want a different future" for Iran.