Following a more than one-year real estate search, Diversified Technologies Inc. has signed a lease extension at a pair of Alexandria Real Estate Equities-owned buildings in Bedford.

Founded in 1987, DTI manufactures power equipment used in applications from food processing to radar systems. Its headquarters occupies 33,320 square feet at 35 Wiggins Ave. and 6-8 Preston Court. The Bedford site includes office, lab and assembly space.

Similar to e-commerce company Demandware, which recently chose to expand in Burlington to provide continuity to senior staff, DTI was committed to the Route 128 north submarket, said Jack Kerrigan, a principal with Avison Young who represented the company. After considering availabilities in Lexington, Burlington, Bedford, Billerica and Chelmsford, DTI decided to avoid the disruption associated with a move, Kerrigan said.

The properties are part of Alexandria Park at 128, which contains 343,992 square feet in eight properties in Lexington and Bedford. The portfolio was 98.1 percent occupied as of Dec. 31.

Average rents for office space in Bedford were $26.26 per square foot in the second quarter, with a 14.3-percent vacancy rate, according to Cushman & Wakefield research.