Hitachi Cable is proud to announce the successful development of two new products for ground wave digital broadcasting. The Company expects strong demand for these products as they meet broadcast company needs to reduce capital investment.

Ground wave digital broadcasting will commence in Japan's three largest cities, Tokyo, Osaka, and Nagoya, by the end of 2003, and will extend to the whole of Japan by 2006. At present, conversion of analog channels to analog channels continues to allot channels for digital broadcasting. Presently, construction of new facilities for ground wave digital broadcasting is beginning. Hitachi Cable is fully aware of the importance of providing systems that offer customers superior cost performance.

Hitachi Cable developed its feeder in 1961. Since then, the Company has created a "total solution" that spans everything from station placement planning and system design to the development, design, manufacturing, construction, and maintenance of antennae and feeders. Hitachi Cable boasts a long history of superior technological ability in the television broadcasting facilities field.

Leveraging this experience, the Company has focused its efforts on developing those products particularly in demand by ground wave digital broadcasting facilities - inexpensive and highly reliable antennae, and the space-saving antenna systems that use these antennae. Hitachi Cable has successfully developed the following two products, which will help broadcasting companies save on capital investments costs.

1. Ultra wide - band stacked loop antenna - able to handle a spectrum three times larger than before

Through precise alignment of elements and feeding components, the ultra wide-band stacked loop antenna is able to handle a spectrum three times larger than before. (picture 1)

Until now, covering all UHF-band channels (13-62) required 4 different types of antennae, and it was quite difficult for a single antenna to handle a large number of channels over a wide wavelength band. However, Hitachi Cable's ultra wide-band stacked loop antenna handles the entire range of channels using just two types of antennae. Because of this, the Company expects that most transmission stations will be able to use fewer antennae, thus making for a significant decrease in installation cost.

2) Matrix feeding system - allows two channels to share a portion of an array antenna and allows each channel to have different vertical directivity (tilt angle)

Two problems that crop up when one is constructing digital broadcasting transmission facilities are cost and land. Because of this, broadcasting companies want to make effective use of existing analog antenna towers. This requires efficient antenna systems.

The matrix feeding system is a system in which analog and digital channels share one portion of an array antenna. (chart 1)

In addition, because array power supply settings can be adjusted relatively easily for each channel, analog and digital channels can have different vertical directivity (tilt angle).

Adopting this system means a shorter overall array length as compared with the separate installation of a dedicated digital antenna. This makes for an antenna with lower wind resistance, and wind resistance can affect tower strength. In other words, this system effectively solves tower strength problems that occur with an increase in the number of antennae, meaning a reduction in strength-related construction cost.

The Company expects that Ultra wide-band stacked loop antenna and Matrix feeding system will be widely praised as efficient solutions for the construction of ground wave digital broadcasting facilities.

These new products will allow Hitachi Cable to provide integrated solutions spanning everything from station placement planning and system design to antenna and feeder delivery and installation. The Company has set a cumulative target of 30.0 billion yen in orders from ground wave digital broadcasting companies.

Development and Manufacturing Site for This Product and System:

Takasago Works
880, Isagosawa-cho, Hitachi City, Ibaraki Prefecture, 319-1418

Picture 1: Ultra wide-band stacked loop antenna

Chart 1: Matrix feeding System

Antenna
Branched feeder
Junction box
Main feeder
Fluctuating distribution
Fluctuating distribution
Shared device
A Channel feeding phase
B Channel feeding phase
Dedicated A channel antenna
A&B channel joint use antenna
Dedicated B channel antenna
A channel directivity (analog)
B channel directivity (digital)