French manufacturer Alcatel Alsthom is acquiring telecommunications equipment maker DSC Communications Corp. for about $4 billion in stock, executives of the companies said. The acquisition would expand the French company's presence in the U.S. telecommunications equipment market. The announcement said Plano, Texas-based DSC's strong position in making telecom access and switching equipment would complement Alcatel's strength in transmission equipment. Paris-based Alcatel and others that compete against Lucent Technologies Inc. in the U.S. are buying smaller rivals to increase the products they can offer the Baby Bells. Tellabs Inc. this week said it would pay $6.86 billion for Ciena Corp. Alcatel fell $4.31 to close at $39.13 per ADR on the New York Stock Exchange, and DSC's shares jumped $7.81 to close at $27.50 on Nasdaq.