Search giant Google is planning to do for radio advertising what it did for search, and its ads are already on the air in Detroit.

Google-powered ads are being played on at least one radio station in the Motor City and are set to soon air all over, writes CNET, citing Google's CEO as saying its radio-ad business will be in full gear within three months. "We are in the process of introducing AdSense for radio, which is essentially the integration of the dMarc console and management tools into our advertising system," Eric Schmidt is quoted as saying.

Google bought into the radio ad business in January with the $102 million acquisition of dMarc Broadcasting and its automated radio advertising system, which has been tweaked for Google's purposes. Google hopes, as in search, that automation will lead to efficiency, lower cost for advertisers and more sales for radio stations.

"I think dMarc is an opportunity for us to connect with advertisers we don't normally interact with," John Fullam, vice-president and market manager for Greater Media Philadelphia, is quoted as saying. "It's big for radio." Google ads are being tested on Greater Media radio stations in Detroit, and "there are a number of very interesting deals being negotiated," according to Schmidt.