Japan’s Digital Television Broadcast System Requires Rubidium Technology

SAN JOSE, Calif. – November 30, 2004 – Symmetricom (NASDAQ: SYMM), a leading worldwide supplier of network synchronization and timing solutions and atomic clocks, today announced that it has begun deploying Rubidium atomic clock oscillators as a critical transmitter component for the emerging Japanese Integrated Services Digital Broadcast-Terrestrial (ISDB-T) system.  The rollout of ISDB-T has begun to be deployed in major metropolitan areas across Japan and will continue through 2010.   

The ISBD-T specification standard established by the Japan Ministry of Posts and Telecommunications requires very precise reference frequencies to operate properly.  Rubidium technology was selected for use in these transmitters due to its high precision, long-term accuracy, low maintenance and ability to hold performance over wide temperature ranges.   

“The stringent timing needed for the ISDB-T program required the use of precise Rubidium oscillators,” commented Phil Mann, VP of market development of Symmetricom.  “We’ve worked closely with Japanese suppliers to the ISDB-T program who favor the performance and compact size of Symmetricom Rubidium oscillators.” 

ISDB-T is one of the digital terrestrial television broadcasting standards used worldwide along with DTV in the U.S. and DVB-T in Europe.  This standard broadcasts in both HDTV and multi-channel standard definition and contains protocols designed to minimize the signal degradation normally found in terrestrial-based systems.   

Compact Rubidium clock technology is also critical for communications applications such as wireless CDMA base stations, wireline central office synchronization, and defense and government due to its long-term accuracy, stability and ability to operate in difficult environments.