AT&T Likely to Get 2.3 GHz

Posted by Sam Churchill on

The FCC will likely approve AT&T’s plan to use WCS spectrum during the next open meeting scheduled for October 17, 2012, the FCC said today. AT&T wants to offer mobile broadband service on 20MHz of 2.3 GHz spectrum it purchased in August along with spectrum holding company NextWave Wireless.

According to AT&T’s FCC filing, the carrier would acquire between 5 and 30 MHz of WCS spectrum from NextWave Wireless in 476 cellular market areas, achieving a maximum of 30 MHz WCS spectrum. AT&T wants between 10 and 25 MHz of WCS spectrum from Comcast in 149 markets and 10 MHz of WCS spectrum from Horizon Wi-Com in 132 markets. Currently AT&T owns 12 MHz on average of WCS across the country.

Currently there is 30 MHz of WCS spectrum broken into two 5×5 MHz paired channels (the A and B Block) and two 5 MHz unpaired channels (the C and D Block). The C and D Blocks are next to the spectrum used by Sirius XM. Under the proposal from AT&T and Sirius XM, AT&T would not use the C and D Block spectrum for mobile service in exchange for more liberal rules on the A and B Block spectrum, thus allowing AT&T to deploy FDD-LTE service in that band.

In May 2010, the FCC approved initial rules to allow mobile broadband providers to offer services on 25MHz of the adjoining WCS band. That vote opened the door to eventual mobile broadband uses, in addition to fixed wireless services, which had previously been permitted.

When it comes to highly populated areas, Nextwave’s holdings include mainly the A, C and D bands. Looking at a county level data, the table above shows the apparent improvement in AT&T’s spectrum position for the top counties ranked by population. But the C and D bands are being taken away by mutual agreement between AT&T and Sirius/XM. AT&T appears to be buying largely nothing from Nextwave (bands C & D), so they can get access to bands A & B, also acquiring spectrum from Comcast and Horizon.

Frank Rayal explains who owns what in the WCS band. It’s the A & B bands that matter. AT&T has to buy the C & D bands so it can use A & B.

In June, AT&T and Sirius/XM came to an agreement allowing mobile broadband on 2.3 GHz. XM uses satellite repeaters which can be thousands of watts. They would likely drown out the adjoining 2.3 GHz band. The reverse could also be true; a 200 mW WCS radio close to an XM receiver could cause interference. The (5MHz x 2) guard band should make things copacetic.

The Satellite Digital Audio Radio Service (SDARS) is used by Sirius, which uses 12.5 MHz of the S band between 2320 and 2332.5 MHz and XM, which uses 12.5 MHz between 2332.5 to 2345.0 MHz.

XM Satellite Radio and Sirius Satellite radio use different kinds of satellite coverage.

Sirius uses a highly elliptical orbit with three satellite, but only two of them broadcast at any given time. Because they can be seen at a higher angle on the horizon, the need for terrestrial repeaters is lessened.

XM has traditionally used geosynchronous satellites, which result in reception problems in canyons or cities. Consequently, XM developed satellite “repeaters” on rooftops in metropolitan areas, providing improved reception. But the satellite repeaters put out thousands of watts and would swamp nearby WCS basestations.

The new FCC proposal would allow mobile broadband on 20MHz of the total 30MHz in the WCS spectrum, according to Tammy Sun, an FCC spokeswoman.

AT&T thinks it will take around four and a half years to make repurposed 2.3 GHz Wireless Communication Service (WCS) spectrum usable for LTE services. The 2.3 GHz band is often used for 4G (LTE) service in other countries, such as China and India.

In addition, AT&T will need to construct the infrastructure to deliver it.

Meanwhile, Dish’s 2.1 GHz satellite spectrum is on the FCC’s front burner. Dish owns 40 MHz of nationwide MSS satellite spectrum it wants to use terrestrially.

If Dish and Clearwire team up, as some observers believe, then AT&T may want to play in that sandbox, too. Clearwire and China Mobile use the same basic technology, have roaming agreements, and will likely have working handsets from Nokia, Motorola, Samsung and others available by mid 2013. Microcell “hot zones” will deliver the goods.

DISH objects to the proposed shift of their uplinks by 5MHz into the 2005-25MHz band, claiming that a 5MHz buffer is needed between their spectrum and the high end of the band, above 2025MHz, and that a shift would cause serious delays for their network buildout plans.

Sprint has said that a 5 MHz shift would help its LTE operations by freeing up more PCS spectrum for auction. Sprint is currently using the 1900 MHz PCS G Block for its nascent LTE network, which allows it to deploy 5×5 MHz channels. But Sprint would like to get access to the adjacent PCS “H Block”, which would give it the ability to deploy 10×10 MHz channels (1910-1920/1990-2000). Both Verizon and AT&T use 10×10 MHz channels in the 700 MHz band.

Dish applied in late 2011 to the FCC to change the satellite companies’ frequencies to terrestrial broadband using LTE-A. The FCC indicated support for the idea in March, but it has yet to authorize the change.

“Today’s action is part of Chairman Julius Genachowski’s continued efforts to remove regulatory barriers that limit the flexible use of spectrum, which is one way he has led the Commission towards helping address the continued ‘spectrum crunch,” said the FCC in a statement.

Related Dailywireless articles include; AT&T Buys 2.3 GHz from NextWave, AT&T Wants 2.3 GHz for LTE, Dish and Sprint Battle over PCS band Extension and Clearwire: On the Hot Zone

Posted by Sam Churchill on Thursday, September 27th, 2012 at 7:33 am .

Leave a Reply