Harmonic Features ATSC Mobile Video Compression Technology at NAB 2009

Sunnyvale, Calif. — April 16, 2009 — Harmonic Inc. (NASDAQ: HLIT) today announced that its market-leading DiviCom® encoders and ProStream™ 4000 multi-screen platform will power ATSC Mobile DTV technology demonstrations at the 2009 NAB Show. The DiviCom Electra® 8000 universal broadcast encoder, Harmonic's newest and most advanced platform, offers a powerful design that reduces bit-rates without compromising video quality, enabling broadcasters to free up valuable spectrum for advanced services such as mobile video delivery. Harmonic's ProStream™ 4000 provides real-time video compression optimized for the ATSC Mobile DTV format suitable for delivery to mobile devices.

Harmonic's solutions will be featured as part of demonstrations of live mobile video from Sinclair's KVCW-TV signal in Las Vegas, at Sinclair Broadcast Group's booth #C8546N, Acrodyne's booth #C1336 and Harmonic's booth #SU7209. The NAB show will be held in Las Vegas from April 20-23.

"The ATSC Mobile DTV standardization effort and the work of the many partners involved in our NAB technology demonstration has resulted in a powerful solution enabling broadcasters to deliver high-quality mobile video services," said Mark Aitken, director of advanced technology for Sinclair Broadcast Group. "It was important for us to promote a best-in-class ecosystem for this emerging mobile technology, and Harmonic has again set a new benchmark for performance with its industry-leading encoding and transcoding solution."

To help assure optimal performance, Harmonic has also been working closely with LG Electronics, co-developer of the ATSC mobile digital TV system (now an ATSC Candidate Standard). LG and its U.S. R&D subsidiary Zenith have provided valuable technical assistance in the development of ATSC Mobile DTV capabilities in Harmonic's world-class encoders.

"Mobile video is clearly an area that gives broadcasters an opportunity to enhance their service offering, and Harmonic's comprehensive portfolio of solutions enables a high-quality multiscreen video experience, whether broadcast or on-demand," said Tom Lattie, director of broadcast and new media solutions for Harmonic. "The Electra 8000 encoder represents the most advanced broadcast compression technology available, and the ProStream 4000 enables operators to transcode or encode to a variety of mobile and Internet video formats, including ATSC Mobile DTV. In addition to real-time compression, Harmonic's MediaPrism™ software suite of aggregation tools is ideal for the repurposing of broadcast video content for new on-demand consumption models, such as Internet and mobile video."

For more information about Harmonic's compression and mobile solutions, please visit www.harmonicinc.com/electra8000 or www.harmonicinc.com/mobile.

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About Sinclair Broadcast Group

Sinclair Broadcast Group, Inc. (NASDAQ: SBGI), one of the largest and most diversified television broadcasting companies, owns and operates, programs or provides sales services to 58 television stations in 35 markets. Sinclair's television group reaches approximately 22% of U.S. television households and is affiliated with all major networks.

About Harmonic Inc.

Harmonic Inc. is a leading provider of versatile and high performance video solutions that enable service providers to efficiently deliver the next generation of broadcast and on-demand services including high definition, video-on-demand, network personal video recording and time-shifted TV. Cable, satellite, broadcast and telecom service providers can increase revenues and lower operational expenditures by using Harmonic's digital video, broadband optical access and software solutions to offer consumers the compelling and personalized viewing experience that is driving the business models of the future.

Harmonic (NASDAQ: HLIT) is headquartered in Sunnyvale, California with R&D, sales and system integration centers worldwide. The Company's customers, including many of the world's largest communications providers, deliver services in virtually every country. Visit www.harmonicinc.com for more information.

This press release contains forward-looking statements within the meaning of Section 27(A) of the Securities Act of 1933 and Section 21(E) of the Securities Exchange Act of 1934, including statements related to: powering ATSC Mobile DTV technology demonstrations at NAB 2009, featuring Harmonic's solutions as part of demonstrations of live mobile video from Sinclair's KVCW-TV signal in Las Vegas, and giving broadcasters an opportunity to enhance their service offering.

Our expectations and beliefs regarding the ATSC Mobile DTV technology demonstrations to be featured at NAB 2009 may not materialize, and actual results could differ materially from those projected. The forward-looking statements contained in this press release are also subject to other risks and uncertainties, including those more fully described in Harmonic's filings with the Securities and Exchange Commission including its recent Reports filed on Form 10-K and Form 10-Q. Harmonic does not undertake to update any forward-looking statements.

EDITOR'S NOTE – Product and company names used herein are trademarks or registered trademarks of their respective owners.

ENDS