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WirelessHD is an initiative by several leading technology and consumer electronics companies to organize an industry-led standardization effort to define a next-generation wireless digital interface specification for consumer electronics and PC products. Specifically, WirelessHD will emerge as a new, industry-led special interest group with the stated goal of enabling wireless connectivity for streaming HD content between source devices and high-definition displays.
WirelessHD will be a formal special interest group that will be comprised of consumer electronics and other technology companies, including those that have historically been responsible for the formation of the world’s leading display standards. WirelessHD will promote and enable the rapid adoption, standardization and multi-vendor interoperability of WirelessHD technology worldwide.
WirelessHD will serve as the first and only wireless digital interface to combine uncompressed high-definition video, multi-channel audio, intelligent format and control data, and Hollywood approved content protection. For end-users, elimination of cables for audio and video dramatically simplifies home theater system installation and eliminates the traditional need to locate source devices in the proximity of the display. Also, the technology will support the development of adapter solutions that will be capable of supporting legacy systems.
The WirelessHD specification has been architected and optimized for wireless display connectivity, achieving in its first generation implementation high-speed rates up to 4 Gbps for the CE, PC, and portable device segments. Its core technology promotes theoretical data rates as high as 25 Gbps, permitting it to scale to higher resolutions, color depth, and range. Coexisting with other wireless services, the WirelessHD platform is designed to operate cooperatively with existing, wireline display technologies.
Recent availability of several new technologies make it possible to achieve the multi-gigabit data rates required for uncompressed video streaming. Such breakthroughs enable low cost, better image quality, and higher performance wireless A/V systems. The key characteristics and focal technologies include:
• High interoperability supported by major CE device manufacturers
• Uncompressed HD video, audio and data transmission, scalable to future high-definition A/V formats
• High-speed wireless, multi-gigabit technology in the unlicensed 60 GHz band
• Smart antenna technology to overcome line-of-sight constraints of 60 GHz
• Secure communications
• Device control for simple operation of consumer electronics products
• Error protection, framing and timing control techniques for a quality consumer experience
Click here to download the WirelessHD Specification Summary
WirelessHD Architecture Overview
The WirelessHD specification defines a wireless video area network (WVAN) for the connection of consumer electronic (CE) audio and video devices. A key attribute of the WirelessHD system is its ability to support the wireless transport of an uncompressed 1080p A/V stream with a high quality of service (QoS) within a room at distances of 10m.
The requirement for high data throughput (greater than 3 Gb/s required) at distances of 10 meters requires a large allocated frequency spectrum. A large amount spectrum is available on an unlicensed basis in many countries in the 60 GHz band. In North America and Japan, a total of 7 GHz is allocated for use, 5 GHz of which is overlapping. The band 57~64 GHz is allocated in North America while 59-66 GHz is allocated in Japan. In addition, Korea and the European Union are considering allowing similar allocations. The regulator agencies allow very high effective transmit power (the combination of transmitter power and antenna gain), greater than 10 W of effective isotropic radiated power (EIRP). High EIRP and wide allocated bandwidth will allow high throughput connections that, however, are very directional.
The WirelessHD specification defines a novel wireless protocol that enables directional connections that adapt very rapidly to changes in the environment. This is accomplished by dynamically steering the antenna beam at the transmitter while at the same time focusing the receiver antenna in the direction of the incoming power from the transmitter. This dynamic beam forming and beam steering utilizes not only the direct path, but allows the use of reflections and other indirect paths when the line-of-sight connection is lost.
The WVAN consists of one Coordinator and zero or more Stations. The Coordinator schedules time in the channel to ensure that the wireless resources are prioritized for the support of A/V streams. The other devices that are a part of the WVAN are referred to as Stations. A station may be the source and/or sink of data in the network. The device that is the Coordinator also acts as a Station in the WVAN and may act as a source and/or sink of data.
