(Reuters) - Telecommunications equipment company CommScope Holding Co Inc set pricing terms for its initial public offering, which could value the company at up to $3.9 billion, about three years after being taken private by Carlyle Group LP in a deal valued at $3.9 billion, including debt. CommScope said it expects the offering of 38.5 million shares to be priced at between $18 and $21 each, raising over $800 million. The company is selling 30.8 million shares in the IPO, with affiliates of Carlyle offering the remaining shares, according to CommScope's regulatory filing on Friday. (http://r.reuters.com/cyq73v) Carlyle will hold an about 75 percent stake in CommScope after the offering, if the underwriters exercise their option to purchase additional shares. CommScope is a major manufacturer of cables that underpin high-speed data networks. It traces its roots to Superior Cable Corp, a telephone cable company created in 1953, and changed ownership several times until it went public in 1997. Hickory, North Carolina-based CommScope in August filed to raise up to $750 million through its IPO. Network equipment makers have been benefiting from a recovery in spending by telecom service providers who are upgrading their networks to handle a surge in data traffic. CommScope said it estimates net sales for the quarter ended September to fall marginally year-over-year to $880-$895 million due to lower broadband sales. The company, which counts AT&T Inc , Verizon Communications Inc and Comcast Corp among its major customers, said it expects operating income for the quarter to be between $95 million and $105 million. CommScope intends to list its common stock on the Nasdaq under the symbol "COMM". JPMorgan, Deutsche Bank Securities and BofA Merrill Lynch are the lead underwriters to the offering. (The story corrects first paragraph to clarify that the buyout deal value included debt.) (Reporting by Aman Shah in Bangalore; Editing by Maju Samuel)