Spectrum Depth or LTE Channels: Which is the best way to compare carriers? February 08, 2016 11:30
Most wireless carrier assessments are focused on the spectrum depth that each carrier controls. This is typically indicated by the number of MHz that a carrier controls (owns) either in a county or a market. Many evaluations are focused on the total MHz that a carrier owns although our Spectrum Ownership Analysis Tool and National Carrier reports break the spectrum depth down by both frequency band (700, Cellular, PCS, AWS, WCS, and EBS/BRS) as well as low-band, mid-band, and high-band. The band breakdowns are important because different bands have better or worse performance for coverage or in-building penetration. Understanding each carriers strengths or weakness for that criteria is important. In addition, since each carrier's LTE deployments have been targeted in specific frequency bands, the frequency band spectrum depth is an important metric to indicate the potential LTE channel size.
LTE Effective Spectrum is a much better indication of a carrier's usable spectrum depth than straight spectrum depth. LTE Effective Spectrum is the sum of the spectrum used by all of a carrier's potential LTE channels. We calculate each carrier's available LTE channels in our Mobile Carrier - Spectrum Ownership Analysis Tool by evaluating the contiguous spectrum that each carrier has in each frequency band.. In the tool, we detail the available LTE channels within each frequency band, but below we simplify the analysis here by listing only the quantity each channel size (5x5, 10x10,...). These LTE channel counts are provided at a CMA market level. To calculate the Effective LTE Spectrum value each of the channel widths (MHz) are summed. For Verizon in the Los Angeles CMA, four 10x10 channels and one 20x20 channel works out to: 4 x 10 + 4 x 10 + 1 x 20 + 1 x 20 = 120 MHz. Each channel is listed twice to reflect both transmit and receive (FDD) spectrum.
As you compare Verizon's Total Spectrum with their Effective LTE Spectrum at a market level, it is apparent that roughly 6% of Verizon's spectrum is not deployable for LTE. For Verizon, this lost spectrum relates to 2.5 MHz slices of cellular spectrum and 1 MHz slices of 700 MHz spectrum.
As you compare AT&T's Total Spectrum with their Effective LTE Spectrum at a market level, it is apparent that a much larger portion of AT&T's spectrum is not deployable for LTE. AT&T loses between 15% and 22% of there Total Spectrum on a market basis. This lost spectrum primarily relates the WCS spectrum (10MHz) AT&T dedicated as a guard band for satellite audio, along with 2.5 MHz slices of cellular spectrum and 1 MHz slices of 700 MHz spectrum.
As you compare T-Mobile's Total Spectrum with their Effective LTE Spectrum at a market level, it is apparent that very little of T-Mobile's spectrum is not deployable for LTE. T-Mobile typically loses 2% of their Total Spectrum on a market basis. This lost spectrum relates to the 6 MHz channels of 700 MHz spectrum only being used for 5x5 LTE. There are specific markets (San Diego @ 9%) where T-Mobile controls a 12.5 MHz channel which can only be deployed as a 10x10 LTE channel effectively losing ability to use the remaining 2.5 MHz unless a new acquisition would add adjacent spectrum.
We have left the analysis of Sprint's Lost Spectrum for another time because Sprint's combination of TDD and FDD spectrum makes their analysis significantly more complicated.
These charts reflect the Future data set from Allnet Insight's Spectrum Ownership Analysis Tool (February 2016 Version).