Charge-Coupled Device Pseudo-Noise Matched Filter Design

Abstmct-The design and fabrication of practicable CCD IC’s as pseudo-noise matched filters (PNMF’s) for directaequence spreadspectrum signals is descn’bed. After a brief explanation of CCD PNMF’s, desirable architectural features fa an IC are presented. A state-of-the art My integrated 512-cell CCD PNMF is used as an example. Next, PNMF design considerations dealing with device Limitations, sampling errors, and carrier-frequency offsets are addressed. The application of PNMF’s to various modulation formats is treated, dong with approaches to increased smpling resolution. Finrlly, hborntory measurements for a 128-cen PNMF as wen as a 512-ceIl PNMF formed by a tandem connected of four of the former are presented. Multiple access, a 60-dB dynamic nnge, and 0.75 percent linearity were achieved with the former, while the latter correlated 255 chips m a double-sampled configuration.