Business Notes COMMUNICATIONS

Motorola has been one of the most pugnacious U.S. companies in trying to enter the Japanese marketplace. The suburban Chicago company's efforts paid off last week in a double win. Against a field that included Japanese bidders, Motorola won the $35 million annual contract to install a cellular-phone network for the Tokyo area.

Then Japanese sources surprised even Motorola officials by leaking word that the company had scored a still more prestigious victory. After a fierce six- month competition with Japanese and European rivals, Motorola was selected to provide the digital voice technology for the Japanese telephone network's next generation of cellular equipment. One of Motorola's prime selling points is believed to be its pocket-size Micro-TAC cellular telephone. Introduced last year, the tiny device is already a coveted gadget in Japan. Motorola's breakthrough sent the electronics company's stock to 80 3/4, up 4 1/8 points for the week.