1816 ET - SpaceX's Starlink is doubling down on its ambitions to become a "major mobile carrier in the U.S." that can compete with AT&T, Verizon, and T-Mobile, COO Gwynne Shotwell says. The company recently bought a large portfolio of 800 MHz spectrum, and got approval from the FCC to launch 15,000 satellites optimized for global 2GHz spectrum. "We will be building out our terrestrial networks," CEO Elon Musk says during a Tuesday earnings call, "so there's broad-based connectivity anywhere that SpaceX and Starlink are allowed to operate." Musk says expects Starlink's total bandwidth to rise around one-hundredfold within the next three years.