Survivability of space systems may depend heavily on the use of decoys, particularly responsive or short-lived decoys, to enhance satellite survivability. Ideally, such decoys for space applications should be simple, effective, lighweight, and low cost. However, a very wide range of radar frequencies can be used to detect, track, and target space objects resulting in differing decoy requirements for differing radar frequencies. The problem is multispectral, requiring differing sizes of decoys to simulate a given satellite signature. One solution is to deploy multiple decoys, each one sized for the various threat radars that might be confronted. This solution has a serious drawback in that, if any of the optimally sized (for a given frequency) decoys are seen simultaneously by two or more radars of different frequencies, then the decoy is exposed as a decoy. An in- herently multispectrkl decoy (imd) for use against radar threat sensors of widely different frequencies is being investigated in this study. Generic but representative rdar threats and kinematics are being defined and analyzed. Various cavity modifications and types of modifications are being explored and evaluated within the threat sensor and kinematics context. When successful, considerable survivability enhancements for future space systems would be achieved.