Pulse or digital communications – Repeaters – Testing
Patent
1995-03-20
1996-10-22
Chin, Stephen
Pulse or digital communications
Repeaters
Testing
375267, 375299, 455 59, H04B 169, H04B 712
Patent
active
055685072
ABSTRACT:
The present invention provides a novel Geometric Harmonic Modulation (GHM) system. The GHM system operates in two modes, a preamble mode and a traffic mode. During the preamble mode, n+1 frequencies are each offset by a predetermined phase offset in the transmit unit and passed through a channel to a receive unit. The set of phase offsets is used as the spreading code in the transmit unit, and also acts as an `address` of receive units to transmit to. The receive unit monitors preamble signals to determine the phase offsets. When it recognizes a set of phase offsets, or `address`, which pertains to itself, the receive unit stores the phase offsets and uses these phase offsets to despread and decode the appended message. After the preamble mode is finished, the GHM modulator enters the traffic mode and requests the message to be transmitted from the message source. A traffic carrier waveform is created by multiplying tones, each having its specific phase offset. An analog or binary message is encoded by modulating the traffic carrier waveform. The receive unit detects a preamble carrier and recovers the particular preamble phase offsets to be used as the despreading `key`. The receive unit then employs the phase offsets in despreading the received signal to recover the transmitted message.
REFERENCES:
patent: 4628517 (1986-12-01), Schwarz et al.
patent: 5034997 (1991-07-01), Iwasaki
U.S. patent application entitled, "Dynamic Code Division Multiple Access Communication System", (Attorney Docket No. RD-24193) J. E. Hershey, A. A. Hassan, G. J. Saulnier.
U.S. patent application entitled "Method of Geometric Harmonic Modulation (GHM)", (Attorney Docket No. RD-23786), J. E. Hershey, G. J. Saulnier A. A. Hassan.
U.S. patent application entitled "Geometric Harmonic Modulation (GHM)--Digital Implementation", (Attorney Docket No. RD-24194), J. E. Hershey, G. J. Saulnier, A. A. Hassan.
U.S. patent application entitled "Geometric Harmonic Modulation (GHM) for Combined Analog/Digital Transmissions", (Attorney Docket No. RD-24195), J. E. Hershey, G. J. Saulnier, A. A. Hassan.
U.S. patent application entitled "Correction of Multipath Distortion in Wideband Carrier Signals", (Attorney Docket No. RD-24196), J. E. Hershey, G. J. Saulnier.
U.S. patent application entitled "Interlaced Geometric Harmonic Modulation", (Attorney Docket No. RD-24223), J. E. Hershey.
Hassan Amer A.
Hershey John E.
Saulnier Gary J.
Chin Stephen
General Electric Company
Gluck Jeffrey W.
Snyder Marvin
Zale Lawrence P.
LandOfFree
Geometric harmonic modulation (GHM) - analog implementation does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Geometric harmonic modulation (GHM) - analog implementation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Geometric harmonic modulation (GHM) - analog implementation will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2365383