Sparse array millimeter wave imaging system

摘要

An active millimeter-wave imaging system that can provide a means of surmounting the deficiencies of earlier millimeter-wave systems, as well as lowering the system cost substantially. Earlier systems have employed large numbers of individual millimeter-wave receivers in either focal plane arrays or frequency scanned antenna arrays, and these systems have suffered from low frame rate, poor contrast, and relatively low resolution. By employing a sparse array of millimeter-wave transmitters and receivers, covering a relatively large, flat, physical aperture, a low cost and high resolution system can be achieved. By employing active millimeter-wave illumination, contrast and frame rate issues can be mitigated, at long ranges (10's of meters). A new approach, termed Fourier Telescopy, allows the illuminating signals to interrogate the various spatial frequencies of the target, and the image to be reconstructed from these various spatial frequency components.