Back in 2010, the FCC Commissioners voted to release the unused television broadcast spectrum sandwiched between each TV channel for use in wireless networking. Known as “white space,” this spectrum was originally allocated as a guard to prevent those channels from interfering with one another. Recent advances in RF Digital Signal processing has ushered in a new generation of “software defined radios” (SDR) that have the precision and agility to dance within and between these spaces, fully exploiting their available capacity without causing interference to existing TV channels.
The FCC’s ruling will put this emerging SDR technology to work opening up significant portions of new Wifi bandwidth that in turn will create significant expansion opportunities for the Wifi Internet Provider. As compared to existing, line of sight Wifi systems operating in the 2.4GHz microwave spectrum, SDR based white space systems utilize spectrum in the VHF and UHF regions where signal propagation mimics that of TV broadcasts; traveling for several miles beyond line of sight with excellent penetration through walls and other obstructions that would normally stifle traditional Wi-Fi signals.
This will allow the Wifi Internet Provider to extend its reach towards the roughly 14 million unserved rural citizens currently denied Internet access due to lack of available and cost effective connectivity. In addition, white space spectrum can provide for Public Access Gateway backhaul to network access nodes currently beyond the reach of traditional Wi-Fi or wired backhaul. This Wi-Fi expansion will also do its part to spur the economy by creating new jobs for installation, operation and maintenance of these deployments.
According to a related article in PC World (1), “Rice professors Edward Knightly and Lin Zhong are likely to be among the first to put the FCC’s new rules to the test thanks to a $1.8M federal grant to establish a white space test bed in East Houston.” The five year project calls for Rice and Houston-based non-profit Technology For All (TFA) to add white space technology to a wide spectrum Wifi network they jointly operate in Houston’s working-class east end neighborhood. Not to be left behind, Microsoft and Google have embraced deployment of white space technology within their own campuses as well.
Investments in white space exploration and emerging frequency-agile SDR technology enable the possibility of opening up other portions of spectrum. Ultimately, SDR technology holds the promise of allowing all frequency spectrum to be shared by everyone, utilizing highly agile SDR’s to continuously scan for available spectrum, dynamically reserving then releasing that spectrum as required. Allowing radios to manage our precious spectrum means much less wasted space and much greater access to needed capacity more rapidly than regulation and politics have brought.