Try our NEW Online Store with a better user experience!

What Is WHDI?

Good question.† And the answer is: Wireless Home Digital Interface.† Doesnít help?† Let us bring you up to speed.† In essence, itís the ability to watch what you want, where you want, without having to relocate any equipment. WHDI allows consumers to connect any of the A/V equipment in their home to any display in their home.† Imagine pulling up a recipe, or even a how-to cooking video, on your PC and being able to see it on the TV in your kitchen.† Maybe the kids want to play their latest and greatest game on the big home theater screen, but the gaming console is set up in another room.† No problem.† And on those nights when you start a movie on the only Blu-Ray player in the den, but want to watch the end as you fall asleep, just change the display to your bedroom TV.† The range spans the whole home and any output source.† Sweet! The system works much like a WiFi network, which enables computers and other electronic devices to be connected to one another without cables but then takes it one step further by transmitting high-definition video signals.† For folks who have hesitated hanging a flat screen TV on the wall because they havenít wanted to battle disguising the wires, or worse, running them behind the walls, worry no more.† That flat screen TV can receive a wireless signal from a router or modem.† The effective range of signals is currently more than 100 feet (30 meters).† The signals are able to be transmitted through walls with latency less than one millisecond.† The link routes the video and the audio separately, but with essentially no latency, the two streams will remain closely aligned, thus avoiding the lip-sync issues one would encounter when watching an old dubbed-over Godzilla movie, for instance. WHDI is based on a revolutionary video-modem technology invented by AMIMON, a fabless semiconductor company headquartered in Israel.† The video coding and modulation of this emerging technology are jointly optimized, enabling capabilities far beyond those of traditional wireless data modems.† WHDI is the first standard to enable wireless transmission in the 5GHz, unlicensed band of uncompressed HD video streams with equivalent video data rates of up to 3 Gbps (including 1080p) using 40 MHz of bandwidth in compliance with FCC regulations.† Video data rates of up to 1.5 Gbps (including 1080i and 720p) can be delivered using 20 MHz of bandwidth, conforming to worldwide 5GHz spectrum regulations. Why is uncompressed video so important?† The answer is really two-fold.† First, it is a legacy issue as most devices output uncompressed video.† Consumers arenít likely to want to take one step backwards to take two forward.† If WHDI were to transmit compressed video, not only would the quality of the video images suffer, but most of the devices consumers already own simply would not be compatible.† Second, it is a content protection issue.† The truth of the matter is that compressed output would allow anyone who gains access to the content to generate perfect replicas, or stated more plainly, pirate the videos.† Uncompressed video requires a very high data rate and cannot be distributed over the Internet or even fit on a DVD.† The data would have to be recompressed to be shared, which would significantly decrease the quality.† Therefore, uncompressed output, especially if it is encrypted, is the most secure interface for content protection as no one would be able to profit from piracy. While the problem is simple, the solution has not been.† Many attempts have been made to provide wireless delivery of high quality, uncompressed video output.† One example was to apply real-time compression; however, the quality suffered, the latency was evident, and the technology was expensive to boot.† Another solution was to approach video transmission as a special case of data delivery using a traditional data modem.† Wireless data modems treat all bits equally and provide the same level of channel impairment to each bit, which works just fine for data.† However, video bits have different levels of importance and need different levels of protection depending on how strong or weak the bits are compared to the whole; so this didnít work either. WHDI gives bits with more visual importance a greater share of the channel resources and transmits them more robustly, while bits with less visual importance receive fewer channel resources thus lessening their impact.† The human eye is unaffected by the errors in the less important bits, and the result is the delivery of very high video rates with very high quality.† Look out George Jetson, soon we will see an image on the screen, push a button, and the item will miraculously appear!