Digital signal processor modem

Boots – shoes – and leggings

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

375 46, G06F 300, H04L 512

Patent

active

046202943

ABSTRACT:
A dual speed, full duplex modem for transmitting and receiving data on a dialed-access telephone line includes a signal processor for storing samples corresponding to a sinusoidal waveform, for selecting samples at intervals determined by the mode in which the modem is operating to synthesize a signal for modulating by data for transmission, and for autocorrelating a received signal at a frequency determined by the mode in which the modem is operating to recover data from the received signal. The signal processor includes configuring input ports, and a microcomputer receives instructions related to the mode in which the modem is to operate to output a mode-configuring word to the configuring inputs. Conversion from the signal processor's digital output to the analog signal to the line and from the line's analog signal to the signal processor's digital input take place through two time-division multiplexed coder-decoders. The stored sinusoid is mu-law compressed. The modem can dual tone, multiple frequency dial. The DTMF pair requires a different amplitude from the amplitude of the synthesized signal for modulating by data for transmission. A power series expansion of the required amplitudes of the DTMF tone pair permits both the synthesized signal for modulating by data for transmission and the tones of the DTMF pair to be calculated from the mu-law compressed sinusoid.

REFERENCES:
patent: 3238299 (1966-03-01), Lender
patent: 3292086 (1966-12-01), Magnuski
patent: 3617889 (1971-11-01), Rabinowitz
patent: 3617941 (1971-11-01), DeLellis, Jr.
patent: 3706929 (1972-12-01), Robinson et al.
patent: 3745250 (1973-07-01), Gerst
patent: 3885105 (1975-05-01), Hildenbrand
patent: 3905028 (1975-09-01), Wintz et al.
patent: 3937882 (1976-02-01), Bingham
patent: 3958191 (1976-05-01), Jones, Jr.
patent: 3987374 (1976-10-01), Jones, Jr.
patent: 3988540 (1976-10-01), Scott et al.
patent: 4003001 (1977-01-01), Jones, Jr.
patent: 4008373 (1977-02-01), Nash et al.
patent: 4085449 (1978-04-01), Walsh et al.
patent: 4263670 (1981-04-01), Sherman
patent: 4290140 (1981-09-01), Malm
patent: 4310721 (1982-01-01), Manley et al.
patent: 4313202 (1982-01-01), Kameya
patent: 4335446 (1982-06-01), Gandini et al.
patent: 4387440 (1983-06-01), Eaton
patent: 4404532 (1983-09-01), Welti
Techo, Data Communications, An Introduction to Concepts and Design, Plenum Press, 1980, pp. 179-180.
M. Choquet and H. Nussbaumer, "Microcoded Modem Transmitters", IBM J. Res. Develop. 338-351 (Jul. 1974).
P. VanGerwen, N. Verhoeckx, H. Van Essen & F. Snijders, "Microprocessor Implementation of High-Speed Data Modems", IEEE Transactions on Communications, vol. Com-25, No. 2, 238-250 (Feb. 1977).
K. Wantabe, K. Inoue & Y. Sato, "A 4800 Bit/s Microprocessor Data Modem", I.E.E.E. Transactions on Communications, vol. Com-26, No. 5, 493-498 (May 1978).
D. Sherman & S. Verma, "System Description of a Programmable Multiple Data Set", National Telecommunications Conference, 23-9 through 23-12 (Dec. 1975).
A. Salazar, D. Sherman, S. Verma & J. Werner, "Implementation of Voiceband Modems on a Digital Signal Processor", National Telecommunications Conference, 23-13 through 23-16 (Dec. 1975).

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Digital signal processor modem does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Digital signal processor modem, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Digital signal processor modem will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-1350712

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.