Dasd-Based Signal Correlators
Original Publication Date: 1984-Oct-01
Included in the Prior Art Database: 2005-Feb-05
Direct-access storage device (DASD)-based signal correlators have a magnetic disk system in which the normal concentric tracks are replaced by one or more continuous spirals, and the disk area is used as, at least, one delay line. Data may be fed into the delay line via a moving write head 11 which follows the spirals 13 using an optical or capacitive servo. One or more read heads 12 serve to extract the data after a time delay given by the radial separation of read 12 and write 11 heads, and the track density/disk velocity combination. The maximum time delay is given by the time taken to write the whole disk surface. Any such delay line may be characterized by a figure of merit called the time bandwidth (TBW) product. This is equivalent to the total number of bits stored in the line.