WPCS International Inc., an Exton-based wireless communications engineering firm, today said it has signed a letter of intent to acquire ATC International Holdings Inc., of Miami, for $2.45 million in cash.

ATC, with $7 million in revenue for 2006, has an office in El Salvador and does wireless engineering for commercial and government clients in Central America. For 2007, the company is projecting revenue of $9.5 million and earnings before interest and taxes of $900,000.

The acquisition is expected to be completed within 60 days, WPCS said.

WPCS shares were up 33 cents, to $10.70, in early trading on the Nasdaq market.