A transpectral sensor array is a 24th century mirror universe sensor device. The device could penetrate the interference caused by plasma storms.
In 2371 in the mirror universe, Jennifer Sisko worked for the Alliance building a transpectral sensor array in an effort to locate hidden Terran Rebellion bases in the Badlands. She did not complete the array because she was persuaded to join the rebels by Benjamin Sisko from the other universe. (DS9: "Through the Looking Glass")