On the Solvability of Linear Matrix Inequalities under Quadratic Constraints
Lev B. Rapoport, Timofey Tormagov · 2020
The use of semidefinite relaxation in the problem of the sign-definiteness of a quadratic form under quadratic constraints allows one to obtain new sufficient conditions for the solvability of a linear matrix inequality (LMI) under quadratic constraints in the case when the S-procedure does not give an answer. Results are illustrated by an example.