Three wireless systems for connecting HDTVs are competing for the home, says EE Times. This “battle of technologies” is being fought between three contending systems, 5 GHz, 60 GHz, and ultra wideband (UWB), according to ABI Research. Most established wireless vendors are waiting to see how the market evolves, says the research firm.
- WirelessHD uses 60-GHz transmission. The bandwidth available at 60 GHz allows data transmissions as fast as 4 Gbits/s. The format is backed by lead technology developer SiBeam, along with Intel, LG, Panasonic, NEC, Samsung, Sony and Toshiba.
- Wireless High Definition Interface (WHDI), using 5 GHz. WHDI, developed by Israeli company Amimon, reportedly achieves a data rate as fast as 3 Gbits/s. WiFi 802.11n technology using MIMO can achieve up to 600 mbps, but cannot yield a 3-Gbit/s data rate. For that, Amimon tapped an existing signal-processing technology called joint-source channel coding.
- WiMedia Alliance uses Ultrawideband (UWB) in a band of frequencies from 4.2 to 4.8 GHz or higher. Their Wireless USB standard claims a data rate of 480 Mbits/s and works by compressing and expanding HD video images.
There is no consensus among consumer manufacturers on a single standard or unified wireless HD format. But wireless connections are expected to simplify A/V installations and allow more flexibility in positioning TVs.
Transmission of uncompressed 8-bit-color, 60-frame/second video requires 1.4-Gbit/s data in 720p resolution, 1.5 Gbits/s at 1080i and 3 Gbits/s at 1080p. A data rate of at least 80 Mbits/s is required to transmit compressed video. Only the 60 GHz format allows completely uncompressed transmission — but range and wall penetration remain issues.
Small numbers of 5 GHz and UWB devices are currently shipping; demo products of 60 GHz systems are expected early next year. “Over the next two to three years, we’re going to see one or two of these wireless HDTV approaches emerge as the primary ones,” says ABI’s Wilson.
