LightSquared has landed a fifth customer, VoIP startup netTALK, amid its struggle to fix a GPS interference issue that could derail its plans for a wholesale LTE network.
The contract with netTALK was announced shortly after LightSquared was forced to change its network deployment plans after tests showed its network caused major blackout in GPS systems, which are located in nearby spectrum bands.
NetTALK plans to use LightSquared's network to offer house-brand mobile Internet services for its customers.
"Our partnership with LightSquared helps fulfill our vision of delivering the most advanced communications services to customers throughout America," netTALK President Anastasios Kyriakides said in a statement.
LightSquared also has a wholesale LTE contract with Best Buy, and has signed reciprocal roaming arrangements with Cellular South, SI Wireless and Open Range.
NetTALK did not respond to questions about whether it was concerned about LightSquared's ongoing efforts to resolve its network's effect on GPS systems, or whether its contract contained conditions protecting netTALK if LightSquared is unable to address the GPS issue.
LightSquared has since said it will deploy in airwaves farther away from GPS bands, but government officials say the plan needs more testing and some in the GPS industry are skeptical about whether the plan will completely solve the interference problem.
The FCC has said it will not allow LightSquared to launch its network until it is able to demonstrate that its service will not affect GPS.