Thomson has today (November 15) been officially appointed as the new chair of Digital UK, the organisation responsible for helping people connect to Freeview.
She will take up the £50,000 a year, two-day-a-week post on January 1, 2013, replacing Barry Cox, who is retiring after seven years in the role.
Thomson has also confirmed that she was "not a candidate" for the BBC director general job, despite previously just losing out in the final round of interviews to George Entwistle, who quit the post at the weekend.
She told The Guardian that she feels it unlikely that Lord Patten would approach her for the role, but kept the door open if the BBC chairman was "incredibly persuasive".
Patten has said that he wants to appoint a new director general for the BBC "within weeks", although he indicated that he wants someone with programme-making experience, which Thomson does not have.
Also in January 2013, Digital UK will be merged with DMOL, the company which runs the Freeview on-screen TV guide.
The combined company will operate under the name Digital UK and provide day-to-day technical management of the Freeview EPG, as well as manage the launch of new channels on the platform and allocate channel numbers.
Digital UK will also continue to work on behalf of the government, co-ordinating changes to TV signals, including clearance of the old 800MHz band formerly used for analogue TV that will be used for 4G mobile from next year.
David Scott, the chief executive of Digital UK, said: "Caroline has been a huge supporter of Digital UK since the company was founded, so I am delighted she has now agreed to be our chair as we take on new challenges.
"I would also like to thank Barry Cox for the vital role he played in helping steward us through the successful delivery of television switchover."
Thomson, who represented the BBC on the Digital UK board from 2006 to 2012, praised Cox as a "brilliant chairman" and said that she was "honoured to have been asked to succeed him".
"Digital UK's talented team has a strong track record of delivering results and, with switchover complete, working with the new board we can now address the strategic challenges of ensuring the free-to-air platform is well managed and that viewers are well served," she said.