INTERMEDIATE FREQUENCY INDEPENDENT STAR MIXER
 Inventors: Joseph Staudinger, Warren L. Seely;
John M. Golio, all of Chandler, Ariz.
 Assignee: Motorola, Inc., Schaumburg, 111.
 Appl. No.: 718,726
 Filed: Jun. 21,1991
 Int. CI.* H04B 1/26
 U.S. CI 455/330; 455/333;
 Field of Search 455/118, 325-326,
455/330, 333; 307/529; 333/32
 References Cited
U.S. PATENT DOCUMENTS
4,531,236 7/1985 Ishihara 455/330
4,603,436 7/1986 Butler 455/333
4,896,374 1/1990 Waugh et al 455/326
5,060,298 10/1991 Waugh et al 455/326
An apparatus for mixing electrical signals including in combination: first signal splitting means having a radio frequency (RF) port and first, second, third and fourth signal ports, second signal splitting means having a local oscillator (LO) port and first, second, third and fourth signal ports, intermediate frequency (IF) port, and mixer element means, the mixer element means coupled to the first, second, third, and fourth signal ports of the first and second signal splitting means and coupled to the intermediate frequency port means, for mixing two of the RF, IF, and LO signals to produce the remaining signal.
25 Claims, 6 Drawing Sheets