From The Editor | January 4, 2013

FCC Opens Door To Dish's LTE-A Network, But Tech Hurdles Loom

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By Paul Kruczkowski, Editor

The Federal Communications Commission (FCC) delivered an early holiday gift in December to Dish Network when it finally granted the company’s year-old request to use its advanced wireless services (AWS-4) spectrum for terrestrial broadband mobile applications. The FCC’s order is a gift in several ways. First, it removes regulatory barriers to an ancillary terrestrial component (ATC) in the 40 MHz of spectrum in the 2 GHz band — 2000 to 2020 MHz (for uplink) and 2180 to 2200 MHz (for downlink) — and provides the service, technical, and licensing rules for Dish Network to move forward with its planed LTE-Advanced network. In addition, the value of the AWS-4 spectrum that Dish Network acquired for $2.9 billion from two ailing companies last year just went up, now that it can be used for broadband mobile. Finally, the approval could be a big gift to the public and the wireless infrastructure industry if this order finally introduces much-needed competition into a wireless market dominated by a few major operators.

As things stand today, we are still a ways off from that reality, and Dish Network will have to contend with some major challenges on its way to deploying its LTE-Advanced network. For one, the FCC has saddled Dish with some stringent out-of-band emission (OOBE) requirements for part of the uplink band that could prove problematic. Dish will be required to meet an OOBE limit of 70 + 10 log10 (P), where P is the power in watts, at 2000 MHz and below — instead of the typical 43 + 10 log10 (P) emissions requirement. That sounds like one heck of a challenging output filter specification to me.  

Additionally, the FCC is restricting the effective isotropic radiated power (EIRP) between 2000 and 2005 MHz to 5 mW instead of the 2 W EIRP permitted for the rest of the 2000 to 2020 MHz band. This reduced power is intended to protect an upper H-Block (1995 to 2000 MHz) base station receiver from overload.  The FCC intends to auction off the H-Block spectrum in 2013, so protecting it from interferers is of the utmost importance in preserving its value. (Because the H-Block is also adjacent to the PCS G spectrum that Sprint Nextel currently owns, Sprint should be interested in acquiring it.)  

The FCC order also came with some network coverage mandates. Dish Network is required to provide service to 40% of the total population in its aggregate service areas within 4 years and 70% within 7 years. It is clear that Dish Network wants to find a partner to help it with the buildout of its network, and major industry player like Sprint Nextel and Google are rumored to be suitors, but at this early date Dish is unable to discuss any such negotiations that are ongoing. 

Although Dish Network is pleased that the FCC has granted terrestrial flexibility for most of the AWS-4 band,  it has raised serious concerns about the limitations that the FCC has placed on the lower part of their AWS-4 spectrum. The FCC has gone out of its way to protect the soon-to-be-auctioned (high-power) upper H-Block from possible interference and overload from the AWS-4 uplink band, but it has not proposed equal protection for the AWS-4 from it lower-adjacent, high-power neighbor. The proposed H-block base stations would transmit 1640 W (EIRP) in non-rural areas and 3280 W peak EIRP in rural areas and have an OOBE limit of 43 + 10 log10 (P) dB outside of the 1995 to 2000 MHz band and a more stringent 70 + 10 log10 (P) dB above 2005 MHz, 5 MHz into the AWS-4 band.

“Thus, we caution any licensee of AWS-4 operating authority against designing or deploying its network (except at its own risk) assuming either of these levels of OOBE protection for the 2000 to 2005 MHz band from the 1995 to 2000 MHz band or low power limits in the 1995 to 2000 MHz band. As noted below, the Commission will not take action to protect licensees of AWS-4 operating authority from interference that arises in such a scenario. We expect that licensees and their equipment suppliers will take this warning into account when establishing technical specifications, including industry standards, and procuring equipment for the band,” the FCC specified in its order.

Dish Network was given a great gift, but the bow has tied its hands, and it may have to move forward knowing that it may only be able to utilize half of the 20 MHz uplink band. It will be interesting to see how Dish decides to overcome these technical issues. Even more interesting will be its quest for a partner that can help them become competitive in the mobile broadband market. I would expect details of Dish’s plans to begin emerging during the first half of 2013, and hopefully those plans will translate to large opportunities for the wireless infrastructure industry.