Accession Number : ADD016320
Title : Phase Shifter for Directly Sampled Bandpass Signals.
Descriptive Note : Patent Application, Filed 31 Mar 94,
Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC
Personal Author(s) : Waters, William M
Report Date : 31 Mar 1994
Pagination or Media Count : 19
Abstract : A phase shifter is comprised of a filter for shifting the phase of directly sampled bandpass signals without having to convert to complex (I,Q) form. An application requiring a plurality of appropriately phase shifted signals is a phased array antenna. In the operation of the filter, a sequence of directly sampled data is passed into an exemplary three-stage storage unit to sequentially store r sub n+1, r sub and r sub n-1 data samples. The r sub n sample is multiplied by cos phi to develop an r sub n cos phi signal, where phi is the desired phase shift angle. At the same time, the r sub n + 1 and r sub n-1 data samples are subtracted from each other and the result is multiplied by w sub 1 sin phi to develop the value W sub 1(r sub n+1-r sub n-1) sin phi. The value is added to r sub n cos phi to produce an estimated sample value r sub n', which is approximately equivalent to data directly sampled from a signal phase-shifted by.
Descriptors : *PHASE SHIFT, *BANDPASS FILTERS, *PATENT APPLICATIONS, *SIGNAL PROCESSING, ANTENNAS, FILTERS, PHASED ARRAYS, SIGNALS, ANTENNA ARRAYS, ANALOG TO DIGITAL CONVERTERS
Subject Categories : Electrical and Electronic Equipment
Radiofrequency Wave Propagation
Distribution Statement : APPROVED FOR PUBLIC RELEASE