LightSquared’s interference issues

Posted in Financials, LightSquared, Operators, Regulatory, Spectrum at 12:27 pm by timfarrar

LightSquared has now confirmed that it will not “continue to roll out our network and meet the rigorous construction timetable that the Commission has made a condition of our authorization” unless the FCC takes “quick, favorable action” to approve its updated business plan, which is described as “an essential building block for our network”.

This answers one of the questions I had last week, when Communications Daily suggested that LightSquared’s request “isn’t expected to be taken up right away”, as it repeats the statement that LightSquared made to the NTIA in its January 6 letter. However, as I noted then, the FCC would presumably need to be convinced that LightSquared is able to raise the funding to move forward before approving the application. Thus it seems there is a binary outcome – either LightSquared does have (or shortly will have) the partners and funding to move forward, in which case the FCC would most likely approve the waiver request quickly, or it does not, in which case the FCC would defer action, making it increasingly harder for LightSquared to attract the partners it needs.

It is interesting to note one subtle difference between the two letters that LightSquared sent to the NTIA and FCC, which perhaps reflects the different audience, but could also indicate that LightSquared is unsure whether the NTIA will ever be convinced to approve its network. The January 6 letter to the NTIA promises that the “final report [on interference issues] will be submitted to the FCC and NTIA so that those agencies may assess progress. If no progress, or insufficient progress, has been made, the FCC and NTIA would review the open issues and require resolution, giving due consideration to the public interest benefits of operation of the LightSquared network and the nationwide GPS system”. However, the January 21 letter to the FCC proposes simply that “we are willing to accept as a condition on a grant of our request the creation of a process to address interference concerns regarding GPS and, further, that this process must be completed to the FCC’s satisfaction before LightSquared commences offering commercial service”. In other words, the NTIA would no longer have control over the process of evaluating the interference concerns, and would therefore presumably be unable to veto the LightSquared network on interference grounds, if the FCC was determined to allow its operation.

One consultant suggests that it is the fault of the GPS community that receivers were not deployed with “proper” filters, which would have been “more expensive”. However, the US GPS Industry Council’s filing on January 7 highlights that GPS receivers may need relatively high sensitivity in the L-band satellite downlink (1525-1559MHz) because this band is also used for Differential GPS satellite broadcasts. As a result, it is hardly surprising that there could be the potential for problems (although the specific outcome will depend on whether GPS receivers actually become overloaded by any excess noise).

In this regard, another filing was made on Friday by Qualcomm, which indicated that they had examined some of the interference issues and determined that a phone using Qualcomm’s AGPS could “avoid self interference to the GPS receiver operating in the GPS L1 band when simultaneously transmitting data via terrestrial LTE on the L Band” by using a currently available filter. However, Qualcomm “has not determined whether this filter provides sufficient protection to avoid interference to the GPS receiver from LTE base stations operating on the L band”. The letter also notes that “Qualcomm is now in the process of evaluating the extent of interference from LightSquared L Band LTE base stations (i.e., downlink) into the GPS receivers of cell phones using Qualcomm’s AGPS solution, particularly legacy phones already in the market today, given the close proximity of the L and GPS L1 bands”.

Given LightSquared’s “record of concern and cooperation” and its “demonstrated…ability…to resolve potential interference issues” with GPS it is somewhat surprising that the potential for interference from LightSquared L Band LTE base stations into GPS receivers has apparently not previously been evaluated. It is also surprising that to date there has been no comment in the record from Nokia Siemens Networks, which is responsible for building and deploying the base stations for LightSquared and might therefore be expected to have a significant interest in resolving the issue (not least to protect its $7B contract).

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