Stability and quadratic performance LMI conditions are presented for spatially interconnected linear time-space-varying (LTSV) systems in input-output form. By extending our previous results, these conditions allow fixed-structure controller synthesis for spatially interconnected LTSV systems. The problem of spatio-temporal dynamic parameter dependence is avoided completely and issues resulting from non-causality of spatially interconnected systems do not occur. Fixed-structure controller design is illustrated by means of a numerical example.