Figure 6

Performance-driven yield enhancement²¹: (a) S-parameters of a microwave coupler for design x⁽⁰⁾ (nominal), design x⁽¹⁾ (degraded power split), and design x⁽²⁾ (enhanced bandwidth at − 20 dB); for clarity, only relevant characteristics are shown; the directions important for yield manipulation are determined by designs x⁽¹⁾ and x⁽²⁾; (b) surface S(t) parameterized by vector t = [t₁ t₂]^T is delimited by the designs x⁽⁰⁾, x⁽¹⁾, and x⁽²⁾; the model domain X_S is a union of intervals S_I(t) for − 1 ≤ t₁, t₂ ≤ 1.