Bell Atlantic Mobile Systems Inc says it has decided on the Code Division Multiple Access technology for its national digital cellular strategy: the Motorola Nortel Communications Inc joint venture will supply the hardware and software for the company’s first deployment in the northeast market in early 1994; Bell Atlantic also said it signed a letter of intent with AT&T Secure Communications Systems to test AT&T Secure’s cellular wireless data equipment over the Bell Atlantic network, which the company expects will make possible error-free transmission of cellular data.