Starbase 045 was a Federation starbase administered by Starfleet in the mid-24th century.
In 2364, Commander Don Dixon, stationed at the starbase, received an order from Commodore Anna Dixon from the Starfleet Operational Support Division concerning starbase operations. The commander was ordered to acknowledge this order on subspace com net security mode 045, code 100 alpha.
At the end of that year, Data read these orders and several others to investigate claims of a conspiracy among the highest members of Starfleet Command. (TNG: "Conspiracy")
The base was never mentioned in dialog; this name came from a mission order.