Paramount Stations Group has struck a deal to acquire another UPN affiliate.PSG said Friday it has an agreement with Centennial Communications to buy UHF outlet WGNT in the 40th-ranked TV market of Norfolk/Portsmouth/Newport News, Va. Financial terms of the deal were not disclosed. Centennial acquired WGNT for $10 million in 1989; the station generated an estimated $7 million in advertising revenue in 1996. The deal, subject to regulatory approval, will bring the number of stations in the PSG fold to 14. Paramount Stations Group, whose parent company Viacom owns 50% of UPN, has been buying and trading top-50 market TV stations at a rapid pace over the past year. It recently has acquired UPN affils in Seattle, Sacramento, New Orleans and other markets, mostly financed by the proceeds from sales of its Big Three affiliate holdings, such as CBS affil KMOV St. Louis. Paramount’s aim in loading up on UPN affiliates is to strengthen the foundation of the fledgling netlet while at the same time delivering a steady stream of revenue and profit, given broadcasting’s traditionally high margins, to its debt-laden parent company.