New high-speed semiconductor technology has enabled the development of affordable, compact wireless systems that can operate in the unlicensed 60 GHz frequency range.
60 GHz systems on the market today offer completely uncompressed HD-SDI operation at 1.5 Gbps, including any embedded audio channels, metadata, SMPTE time code, etc. Because the signals are uncompressed, no encoding/decoding delay is present in the system, making it ideal for sports, live interviews and other time-sensitive applications. Solutions are also available in the 70/80 GHz and the 90 GHz frequency bands, including high speed Ethernet links that can support bi-direction GigE speeds, which is great for high performance IP video and audio networking.
Signals operating at these very high frequencies (also known as the millimeter band) have properties that offer some important advantages for video transmission. First and foremost, these signals are readily absorbed by the atmosphere, so there is a significantly reduced chance of a signal propagating beyond its intended receiver. This property also greatly reduces the amount of interference from other sources, and makes it possible for many devices to be used in close proximity. Another advantage of high radio frequencies are their short wavelengths, which permit use of very small, high-gain parabolic or horn antennas. These allow highly focused radio beams to be used, further limiting spurious reception and signal interference. Of course, there are limits to the distances over which these signals can be used, with a practical limitation of about 600m or 2000ft. Fortunately, this range is more than adequate for most venues.
One other significant advantage of the 60 GHz band is the fact that these frequencies are globally unlicensed. This means that 60 GHz systems can be used essentially anywhere, and do not require a permit from the FCC or other local agency. This can be a boon for rapid deployment applications where quick installation is paramount.