Small Cells Rulemaking: 3550-3650MHz - Citizens Broadband Service (CBS) Fri, Jan 04, 2013

Interesting facts from the Small Cell Rulemaking. A signal at 3.5GHz would have 29% reduced range compared to BRS/EBS (2.5GHz), 45% compared to PCS (1.9GHz) and 75% compared to the Cellular (850MHz) bands.

Half of this band is currently used for receive frequencies for earth/satellite stations in 37 cites and adjacent radar systems exist from 3650-3700MHz.

There will be large exclusion zones due to incumbent use of the spectrum. West Coast, East Coast, Gulf Coast, Hawaii, and Guam. Approximately 190 million people or 60% of the US population would not have access to small cell technology in the 3.5GHz band. From the map below, the only Top 10 markets that could use this frequency band would be Chicago and Detroit with Detroit being a question mark due to issues with Canada.

FCC 12-148A1 - Figure 2

FCC Small Cell Definition

Small cells are low-powered wireless base stations intended to cover small indoor or outdoor areas ranging in size from homes and offices to stadiums, shopping malls, and metropolitan outdoor spaces. Small cells are typically used to extend wireless coverage to areas where macro cell signals are weak or to provide additional data capacity in areas where existing macro cells are overloaded. Small cells are also characterized by their inclusion of novel sensing technologies such as environmental recognition and auto-configuration. (Paragraph 30, FCC 12-148A1)

The FCC has proposed a multi-tier licensing framework:

Incumbent Access - federal and grandfathered Fixed Satellite Service (FSS) providers
Priority Access - critical services including hospitals, utilities, state, and local governments
General Authorized Access (GAA) - commercial, opportunistic users as well as business and homeowners. GAA users would be required to register in the SAS.

A Spectrum Access System (SAS) similar to the Television Whitespace Database used to coordinate unlicensed usage of the UHF broadcast TV whitespace. SAS would manage CBS access and ensure that lower tiered users will not harm federal and FSS users.

Sprint Small Cells (Not Small Cells) Thu, Dec 27, 2012

Sprint Small Cells - Light Reading

Above is a link to a Light Reading interview with Sprint VP of Network Development and Engineering Iyad Tarazi. The hot topic in wireless is small cells. Clearly the carriers are blurring the definitions of small cells to demonstrate that they have a large installed base or are significantly down the road for new network installations. From Iyad's interview, Sprint has over 500,000 femto cells providing primarily indoor coverage enhancements to customer residences. These are using the customer's broadband service for connectivity and do not support handover of voice or data calls. (Calls drop as you leave home and need to be re-originated on the carrier network. Iyad describes the small cell developments for their LTE coverage. It is not stated, but it is likely that this development is only for their PCS G frequency block, not Clearwires forthcoming LTE. In addition, I would challenge whether they meet the definition for small cells. Sprint is continuing down the path of a non-network integrated coverage device. Whether installed in a small business or a residence, the products Iyad described are not integrated with Sprint's macro network, do not provide interference protection to that network, and will not hand over voice or data calls over without dropping the connections. This is really no improvement to providing WiFi coverage and is deceptive to include in the small cell discussion where a prerequisite should be to provide seamless integration with the macro network. What Sprint has solved for their version of the "small cell" is the impact of providing cost effective backhaul connectivity to the small cell. In all of the cases that Sprint has developed a "small cell" product, they are utilizing the customers backhaul facility for connectivity. To get true integration with their carrier/macro network, Sprint will need to provide and pay for backhaul to their facilities for small cells.