  We develop a technique for blind signal identification of the Starlink
downlink signal in the 10.7 to 12.7 GHz band and present a detailed picture of
the signal's structure. Importantly, the signal characterization offered herein
includes the exact values of synchronization sequences embedded in the signal
that can be exploited to produce pseudorange measurements. Such an
understanding of the signal is essential to emerging efforts that seek to
dual-purpose Starlink signals for positioning, navigation, and timing, despite
their being designed solely for broadband Internet provision.
