05369779 is referenced by 10 patents and cites 6 patents.

A first mixer block converts received MMDS channel frequencies to MMDS frequencies capable of being processed by an MMDS decoder. The MMDS decoder, which includes a crystal controlled reference generator, is located in a benign environment. The reference is supplied to a phase locked loop for controlling a fixed frequency local oscillator that supplies the first mixer. The local oscillator output is also supplied to a second mixer that produces a response signal, of a different frequency, by biphase shift key modulation of said reference that is transmitted back to the transmitting site via the antenna. A squelch circuit precludes transmission of the unmodulated reference.

Title
Two-way MMDS communications system
Application Number
8/84655
Publication Number
5369779
Application Date
June 28, 1993
Publication Date
November 29, 1994
Inventor
Larry K Moreland
McHenry
IL, US
Assignee
Zenith Electronics
IL, US
IPC
H04N 7/14
H04B 1/40
H04H 1/00
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