Makers of car navigation systems plan to release new products this summer that will show high-definition television broadcasts and provide more accurate traffic forecasts.

The dual-use gadgets will make use of land-based digital broadcasting and follow the start in April of so-called one segment broadcasting, a new type of digital terrestrial broadcasting for mobile phones and car navigation equipment simply dubbed One Seg.

On June 15, Matsushita Electric Industrial Co. will release a new version of its Strada car navigation system that features a tuner for digital terrestrial broadcasting.

Matsushita, maker of the Panasonic brand, has developed technology that allows One Seg and other types of high-quality broadcasts to automatically segue into each other, depending on radio wave conditions.

Consumer electronics maker Sanyo Electric Co. has succeeded in miniaturizing its systems jointly with Nissan Motor Co. The new products will be loaded into Nissan vehicles.

On July 1, Fujitsu Ten Ltd., an affiliate of computer maker Fujitsu Ltd., will market a model under the Eclipse brand that automatically studies traffic information and shows less congested routes more effectively than previous models.

Audio equipment maker Pioneer Corp.'s new system, due out later this month, can memorize parking lot entrances a driver once used and automatically guide a car there when the driver uses the same destination.

Among other systems with special features, a product Sanyo launched last month warns drivers with chimes when their habits, such as excessive idling, are determined harmful to the environment.

Matsushita has developed a system that displays alerts during natural disasters and helps drivers search for evacuation sites.