Pulse or digital communications – Repeaters – Testing
Patent
1992-02-12
1994-05-17
Chin, Stephen
Pulse or digital communications
Repeaters
Testing
375 17, 375 36, 375 38, 370 32, 455 73, H03K 700
Patent
active
053134923
ABSTRACT:
A data modulator/demodulator (MODEM) for converting main data and subdata to a baseband signal and an FSK (Frequency Shift Keying) modulated wave, respectively, frequency division multiplxing the baseband signal and FSK modulated wave to produce a transmit signal, and sending the transmit signal over a metallic cable. The MODEM controls the levels of the baseband signal and FSK modulated wave on the output thereof in association with the carrier frequency of the FSK modulated wave such that the levels of the baseband signal and FSK modulated wave simultaneously coincide with respective minimum necessary levels of the terminal of the cable at such a terminal. This is successful in maximizing the transmittable distance by making the most of the power of the transmit signal. Especially, when the total output power of the transmit signal is limited, the ratio of the output levels of the baseband signal and FSK modulated wave is changed in matching relation to the data rate to thereby maximize the transmittable distance at each of the data rates.
REFERENCES:
patent: 4756007 (1988-07-01), Qureshi et al.
patent: 4860308 (1989-08-01), Kamerman et al.
patent: 4891806 (1990-01-01), Farias et al.
patent: 5048054 (1991-09-01), Eyuboglu et al.
Hashimoto Akira
Nishimura Yusuke
Chin Stephen
NEC Corporation
Tse Young
LandOfFree
Data modulator/demodulator does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Data modulator/demodulator, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Data modulator/demodulator will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-883226