We have entered the Mobile Age, and it happened fast. Humankind’s invention and rapid adoption of the cell phone service is an advance greater than the Iron Age, Industrial Age, or the Computer Age. By 2020 almost everyone on Earth will have a mobile phone. In other words, while it took 30 years to reach 3.7 billion mobile users, it will take just 5 years to reach another 5 billion. We have just begun to connect.
The U.S. has led the cell phone revolution, first with the Bell system rollout in 1983 of a 2G nationwide cellphone network. Smartphones now account for 50 percent of the global phones and 80 percent of the cellular phones in the U.S. Smartphones enable YouTube (News - Alert), Snapchat, Skype, WhatsApp, Facebook, or email. The typical user understands that smartphones connect with free unlicensed Wi-Fi and paid licensed 4G LTE with data caps and often slow data speeds. Without unlicensed 2.4GHz and 5GHz spectrum, Apple’s (News - Alert) iPhone, the mobile device that led the smartphone revolution, would have had limited use. Steve Jobs even wanted to create an open Wi-Fi consortium as a way to circumvent slower cellular data speeds.
Mobile providers continue to gobble up new auctioned spectrum. The FCC (News - Alert) recently auctioned spectrum licenses for a whopping $45 billion. Next year, the FCC plans to auction even more spectrum, 84MHz to 126MHz, in the 600MHz TV Incentive Auction. The FCC is attempting a balancing act of maintaining solid blocks of unlicensed spectrum in the TV bands. Since 2008, the FCC has promoted the use of unlicensed spectrum in the TV band, under the name TV white spaces. Even though unlicensed spectrum in 2.4GHz and 5GHz has been so successful in launching the smartphone and making the smartphone usable in areas where cell service is lacking, such as behind the brick walls of a home or office, the FCC has tended to favor licensed spectrum over unlicensed. Nevertheless, the FCC has stuck to its commitment, avoiding “regulatory uncertainty,” by keeping some unlicensed spectrum available in the 600MHz band for TV white spaces devices.
In the FCC TV Incentive Auction, TV stations will voluntarily sell their 6MHz TV channel located in the 600-700MHz band in a reverse auction and, once sold, go off the air. The FCC will then in a forward auction offer the freed up TV spectrum to mobile firms. Following standards for LTE, the FCC established a guard band called the duplex gap between the LTE mobile uplink service (where cell phones transmit data up to base stations) and downlink services (where LTE base stations transmit services down to cell phones). The duplex gap will be 11MHz wide, the size of almost two TV channels. The location of the duplex gap frequency will depend on the amount of spectrum recovered. Of the 11MHz in the duplex gap, 6MHz will be available for unlicensed spectrum for TV white spaces device broadband use. Licensed wireless microphones needed for delivering breaking news events will receive the other 4MHz, with 1MMz for protecting the downlink. Even if the microphones are never used in a particular geographic area, the FCC will keep 4 MHz of spectrum empty, creating a new band of fallow spectrum.
Because TV channel frequencies vary by area, the FCC required that the broadband radios using the spectrum connect to a database. The database uses the location of the broadband radio to direct the radio to unlicensed spectrum. In addition to the new duplex gap, the FCC is creating a 6MHz guard band between the LTE downlink and the closest TV station. White spaces broadband radios will be able to operate within the guard band as well, but will not be able to use the 3MHz frequency closest to the TV station to prevent interference with TV sets that could be nearby.
If the FCC’s TV Incentive Auction sounds complex that’s because it is. However, spectrum can be efficiently allocated using a cloud database connected to an agile radio changing spectrum frequency and power as directed by the database. Wireless devices not connected to a cloud database will become a thing of the past. Unlicensed Wi-Fi 2.4GHz and 5GHz spectrum created the smartphone revolution by allowing for large amounts of free data use. Now the FCC should be encouraged to remember Steve Jobs (News - Alert) and the significant positive results Wi-Fi delivered. Allocating solid blocks of unlicensed spectrum in the TV Incentive Auction is vital for the success of the mobile industry and our future mobile growth. More unlicensed is better.
Edited by Kyle Piscioniere