Multiplex communications – Channel assignment techniques – Combining or distributing information via code word channels...
Patent
1995-12-29
1998-11-24
Pham, Chi H.
Multiplex communications
Channel assignment techniques
Combining or distributing information via code word channels...
370479, 371 431, 375303, H04J 1300
Patent
active
058417761
ABSTRACT:
A method and apparatus for implementation of a code division multiple access encoding scheme in a fiber-optic network. One preferred embodiment of the present invention provides an encoder and decoder for each terminal in the communications network, for example SONET OC-3, and allows each terminal to transmit their signals into the fiber-optic network at random. Because no time slot management is used, signals from all terminals interfere with one another. A coding technique is used by each decoder to sort its own signal out of this interference. The encoded data from each terminal is modulated with a technique known as MFSK (multiple frequency shift keying). The modulated signal is further used to intensity-modulate a semiconductor laser diode which may or may not be a single wavelength laser. At the receiver, the combined interference signal is first detected by a optical intensity detector and then sent to a frequency tone detectors which demodulate the MFSK signal. The output of the MFSK demodulator is then sent to a decoder where the original data bits are recovered. The network employs an optimum spread spectrum multiple access coding and modulation method that hops the subcarrier of a semiconductor laser diode over the entire range of DC -30 Ghz. Powerful concatenated Reed-Solomon outer, dual-K convolutional inner codes are used to minimize errors caused by mutual interference.
REFERENCES:
patent: 4905003 (1990-02-01), Helferich
patent: 5206882 (1993-04-01), Schloemer
patent: 5465267 (1995-11-01), Todoroki
patent: 5499236 (1996-03-01), Giallorenzi et al.
patent: 5500856 (1996-03-01), Nagase et al.
patent: 5511096 (1996-04-01), Huang et al.
patent: 5623485 (1997-04-01), Bi
Viterbi, A.J., "A Processing Satellite Transponder for Multiple Access by Low-Rate Multiple Users," Digital Satellite Communications Conference, Montreal, Oct. 23-25, 1978.
Goodman, D.J. et al., "Frequency-Hopped Multilevel FSK for Mobile Radio", 59 B.S.T.J. pp. 1257-1275, 1980.
Lucent Technologies - Inc.
Pham Chi H.
Yao Kwang B.
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