RF Micro Devices, anticipating growing demand for its wireless chip products, is going to build new facilities in Greensboro and Mooresville and will add 350 jobs, the company said Friday morning.

RFMD (Nasdaq: ) announced its $118 million expansion plan after the state of North Carolina’s Department of Commerce and the governor’s office approved economic incentives worth as much as $4.25 million.

The Greensboro-based company also received $1.2 million in incentives from the city of Greensboro and $1 million from Iredell County, where the Mooresville facility will be built.

Three hundred of the additional jobs will be located in Greensboro, the other 50 in Mooresville. The jobs will be added over a four-year period.

RFMD went ahead with the expansion in North Carolina after reviewing several other states and China as possible locations. The company also was not dissuaded when Guilford County ruled out an incentives package worth $1 million.

“This is RF Micro Devices’ fourth major facility in Guilford County in the 16 years since it opened,” Gov. Mike Easley said in a statement. “The company’s sustained ability to grow in our state shows that we are providing the skilled work force that businesses need and the kind of helpful business climate that allows them to succeed.”

RFMD said it expects demand for its chips to increase as more consumers and companies worldwide embrace wireless 3G, or third-generation, networks. A 3G network provides multimedia services at much faster speeds than earlier network technology.

RFMD also expects growth in the WiMax sector. This technology provides high speeds for wireless data transmission and will be deployed by some network providers, including Sprint.

The expansion in Guilford County will cost $103 million, the Mooresville facility $15 million.

RFMD employs about 1,800 people in Guilford County now.

“The markets served by RFMD are growing, and RFMD is growing its compound semiconductor content within these markets,” said RFMD Chief Executive Officer Bob Bruggeworth, in a statement.

“The addition of our third ‘fab’ will enable us to capture a greater percentage of this growth while also reducing manufacturing costs and driving continued improvement in operating profitability,” Bruggewroth added.

Fab refers to the production facility used for semiconductors.

RFMD received some good news on Thursday when the company said the U.S. government would not block its $900 million acquisition of Sirenza Microdevices. RFMD announced the deal in August.

The average salary of the RFMD jobs is expected to be $42,000 not including benefits.

RFMD will receive a Job Development Investment Grant from the state. The JDIG was approved Friday morning by the state’s Economic Investment Committee.

As part of the grant, RFMD will contribute $1.4 million to the state’s Industrial Development Fund. That fund is used to make infrastructure improvements in economically distressed areas of the state.

If RDM meets the new jobs commitment as spelled out in the grant, the state will grant back to the company 70 percent of personal income taxes paid to new employees.

The jobs must be sustained for 11 years.